Elongation factor 4（EF4） is one of the highly conserved translational GTPases, whose functions are largely unknown. Structures of EF4 bound ribosomal PRE-translocation and POST-translocation complexes have both been...Elongation factor 4（EF4） is one of the highly conserved translational GTPases, whose functions are largely unknown. Structures of EF4 bound ribosomal PRE-translocation and POST-translocation complexes have both been visualized. On top of cellular, structural, and biochemical studies, several controversial models have been raised to rationalize functions of EF4. However, how EF4 modulates elongation through its interactions with ribosomes has not been revealed. Here, using single-molecule fluorescence resonance energy transfer assays, we directly captured short-lived EF4·GTP bound ribosomal PRE and POST translocation complexes, which may adopt slightly different conformations from structures prepared using GDP, GDPNP, or GDPCP. Furthermore, we revealed that EF4·GTP severely impairs delivery of aminoacyl-tRNA into the A-site of the ribosome and moderately accelerates translocation. We proposed that functions of EF4 are to slow overall elongation and to stall majority of ribosomes in POST states under stress conditions.展开更多
Ribosome-like particles have been found in the proplastids in young cotyledon cells of lotus (%Nelumbo nucifera Gaertn% L.). Following the development of young embryo, some lamellar structures and tubular complex occu...Ribosome-like particles have been found in the proplastids in young cotyledon cells of lotus (%Nelumbo nucifera Gaertn% L.). Following the development of young embryo, some lamellar structures and tubular complex occurred in the plastids in young cotyledon cells, and some ribosome-like particles appeared in the loose region of these membrane system and stroma. About 15- 20 d after fertilization, with the further development of plastid, a large number of starch and DNA were synthesized in the plastids, and the plastids contained abundant and clear morphologically ribosomes, some of which presented spiral structure. About 16-18 d after fertilization, amyloplasts were isolated and purified from cotyledon of lotus, and ribosomes bands were obtained by use of sucrose density gradient centrifugation of ribosomes isolated from amyloplasts. RNA and protein contents of ribosomes have also been determined.展开更多
Elucidating protein translational regulation is crucial for understanding cellular function and drug development.A key molecule in protein translation is ribosome,which is a super-molecular complex extensively studied...Elucidating protein translational regulation is crucial for understanding cellular function and drug development.A key molecule in protein translation is ribosome,which is a super-molecular complex extensively studied for more than a half century.The structure and dynamics of ribosome complexes were resolved recently thanks to the development of X-ray crystallography,Cryo-EM,and single molecule biophysics.Current studies of the ribosome have shown multiple functional states,each with a unique conformation.In this study,we analyzed the RNA-protein distances of ribosome(2.5 MDa)complexes and compared these changes among different ribosome complexes.We found that the RNA-protein distance is significantly correlated with the ribosomal functional state.Thus,the analysis of RNA-protein binding distances at important functional sites can distinguish ribosomal functional states and help understand ribosome functions.In particular,the mechanism of translational attenuation by nascent peptides and antibiotics was revealed by the conformational changes of local functional sites.展开更多
Ribosome biogenesis,which takes place mainly in the nucleolus,involves coordinated expression of preribosomal RNAs(pre-rRNAs)and ribosomal proteins,pre-rRNA processing,and subunit assembly with the aid of numerous ass...Ribosome biogenesis,which takes place mainly in the nucleolus,involves coordinated expression of preribosomal RNAs(pre-rRNAs)and ribosomal proteins,pre-rRNA processing,and subunit assembly with the aid of numerous assembly factors.Our previous study showed that the Arabidopsis thaliana protein arginine methyltransferase AtPRMT3 regulates pre-rRNA processing;however,the underlying molecular mechanism remains unknown.Here,we report that AtPRMT3 interacts with Ribosomal Protein S2(RPS2),facilitating processing of the 90S/Small Subunit(SSU)processome and repressing nucleolar stress.We isolated an intragenic suppressor of atprmt3-2,which rescues the developmental defects of atprmt3-2 while produces a putative truncated AtPRMT3 protein bearing the entire N-terminus but lacking an intact enzymatic activity domain We further identified RPS2 as an interacting partner of AtPRMT3,and found that loss-of-function rps2a2b mutants were phenotypically reminiscent of atprmt3,showing pleiotropic developmental defects and aberrant pre-rRNA processing.RPS2B binds directly to pre-rRNAs in the nucleus,and such binding is enhanced in atprmt3-2.Consistently,multiple components of the 90S/SSU processome were more enriched by RPS2B in atprmt3-2,which accounts for early pre-rRNA processing defects and results in nucleolar stress.Collectively,our study uncovered a novel mechanism by which AtPRMT3 cooperates with RPS2B to facilitate the dynamic assembly/disassembly of the 90S/SSU processome during ribosome biogenesis and repress nucleolar stress.展开更多
Background:Axonal degeneration and defects in neuromuscular neurotransmission represent a pathological hall-mark in spinal muscular atrophy(SMA)and other forms of motoneuron disease.These pathological changes do not o...Background:Axonal degeneration and defects in neuromuscular neurotransmission represent a pathological hall-mark in spinal muscular atrophy(SMA)and other forms of motoneuron disease.These pathological changes do not only base on altered axonal and presynaptic architecture,but also on alterations in dynamic movements of organelles and subcellular structures that are not necessarily reflected by static histopathological changes.The dynamic inter-play between the axonal endoplasmic reticulum(ER)and ribosomes is essential for stimulus-induced local translation in motor axons and presynaptic terminals.However,it remains enigmatic whether the ER and ribosome crosstalk is impaired in the presynaptic compartment of motoneurons with Smn(survival of motor neuron)deficiency that could contribute to axonopathy and presynaptic dysfunction in SMA.Methods:Using super-resolution microscopy,proximity ligation assay(PLA)and live imaging of cultured motoneu-rons from a mouse model of SMA,we investigated the dynamics of the axonal ER and ribosome distribution and activation.Results:We observed that the dynamic remodeling of ER was impaired in axon terminals of Smn-deficient motoneu-rons.In addition,in axon terminals of Smn-deficient motoneurons,ribosomes failed to respond to the brain-derived neurotrophic factor stimulation,and did not undergo rapid association with the axonal ER in response to extracellular stimuli.Conclusions:These findings implicate impaired dynamic interplay between the ribosomes and ER in axon terminals of motoneurons as a contributor to the pathophysiology of SMA and possibly also other motoneuron diseases.展开更多
Cytoplasmic accumulation of TDP-43 is a pathological hallmark of amyotrophic lateral sclerosis(ALS)and other neurodegenerative diseases.While current studies have primarily focused on gene regulation mediated by full-...Cytoplasmic accumulation of TDP-43 is a pathological hallmark of amyotrophic lateral sclerosis(ALS)and other neurodegenerative diseases.While current studies have primarily focused on gene regulation mediated by full-length nuclear TDP-43,the potential effects of cytoplasmic TDP-43 fragments remain less explored.Our previous findings demonstrated that primate-specific cleavage of TDP-43 contributes to its cytoplasmic localization,prompting further investigation into its pathological effects.In the cynomolgus monkey brain,we observed that mutant or truncated TDP-43 was transported onto the ribosome organelle.Ribosome-associated transcriptomic analysis revealed dysregulation of apoptosis-and lysosome-related genes,indicating that cytoplasmic TDP-43 induces neurotoxicity by binding to ribosomes and disrupting mRNA expression.These findings provide mechanistic insights into the gain-of-function effects of pathological TDP-43.展开更多
PURPOSE:To investigate the differences in gut microbial characteristics between two traditional Chinese syndromes of premature ovarian insufficiency(POI).METHODS:Forty women with POI were recruited from the Department...PURPOSE:To investigate the differences in gut microbial characteristics between two traditional Chinese syndromes of premature ovarian insufficiency(POI).METHODS:Forty women with POI were recruited from the Department of Traditional Chinese Medicine at Shenzhen Maternity and Child Healthcare Hospital between June and December 2020.Women with POI were divided into the kidney deficiency and blood stasis syndrome(SDBS)and Qi and blood deficiency syndrome(QBDS)groups.Gut microbial community profiles were analyzed by 16S rRNA gene sequencing using an Illumina Mi Seq system.A retrospective study comparing hormone levels and gut microbiota information was performed between the SDBS and QBDS groups.RESULTS:Compared with the QBDS group,the serum levels of estradiol(E2)and anti-Müllerian hormone(AMH)were significantly decreased in the SDBS group.The quantities of Adlercreutzia,Eggerthella,Klebsiella,and Paraprevotella significantly increased in the SDBS group,whereas Lactobacillus decreased significantly.Moreover,alterations in the microbiome in the SDBS and QBDS groups were closely related to the levels of E2 and AMH.The area under the receiver operating characteristic curve for the classification of the two syndromes by the gut microbiome was 0.71.CONCLUSIONS:There were significant differences in the dominant microbiota between the SDBS and QBDS groups,and the change in Proteobacteria in the QBDS group was more significant.The characteristics of gut microbiota help us differentiate between the SDBS and QBDS groups,which may provide a basis for the objectification of TCM syndrome types.展开更多
BACKGROUND Anal fistula is increasingly prevalent due to modern lifestyle factors,and surgery remains the primary treatment.However,the rising incidence of antibiotic resistance,particularly to cefuroxime,complicates ...BACKGROUND Anal fistula is increasingly prevalent due to modern lifestyle factors,and surgery remains the primary treatment.However,the rising incidence of antibiotic resistance,particularly to cefuroxime,complicates perioperative management.The role of gut microbiota in influencing this resistance is not well understood.AIM To investigate the relationship between gut microbiota composition and cefuroxime resistance in anal fistula patients and to assess probiotic intervention impact.METHODS This study included 30 anal fistula patients categorized into cefuroxime-sensitive(Cefur-S)and cefuroxime-resistant(Cefur-NS)groups.Gut microbiota samples were collected during colonoscopy,and 16S ribosomal DNA sequencing was performed to analyze microbial diversity.Patients in the Cefur-NS group received a 7-day course of Clostridium butyricum tablets.Post-intervention,microbial composition and cefuroxime resistance were reassessed.RESULTS Alpha and beta diversity analyses showed no significant differences in microbial diversity between the Cefur-S and Cefur-NS groups.However,effect size analysis identified Roseburia and Butyricicoccus as dominant genera in the Cefur-S group,with higher butyrate production potentially protecting against cefuroxime resistance.Post-intervention,the Cefur-NS group showed a significant reduction in cefuroxime resistance,improved stool consistency,and reduced bowel movement frequency.CONCLUSION This study suggests that specific gut microbiota,particularly Butyricicoccus and Roseburia,may mitigate cefuroxime resistance in anal fistula patients by increasing butyrate production.Probiotic intervention targeting gut microbiota composition presents a promising strategy for reducing antibiotic resistance and improving clinical outcomes.展开更多
Ribosomally synthesized and post-translationally modified peptides(RiPPs)constitute a vast and diverse family of bioactive peptides.These peptides,synthesized by ribosomes and subsequently modified by various tailorin...Ribosomally synthesized and post-translationally modified peptides(RiPPs)constitute a vast and diverse family of bioactive peptides.These peptides,synthesized by ribosomes and subsequently modified by various tailoring enzymes,possess a wide chemical space.Among these modifications,radical S-adenosylmethionine(rSAM)enzymes employ unique radical chemistry to introduce a variety of novel peptide structures,which are crucial for their activity.This review examines the major types of modifications in RiPPs catalyzed by rSAM enzymes,incorporating recent advancements in protein structure analysis techniques and computational methods.Additionally,it elucidates the diverse catalytic mechanisms and substrate selectivity of these enzymes through an analysis of the latest crystal structures.展开更多
BACKGROUND Tacrolimus(FK506)is a key calcineurin inhibitor used to prevent organ transplant rejection and is effective in improving graft survival.However,it is linked to hyperglycemia and insulin resistance,contribut...BACKGROUND Tacrolimus(FK506)is a key calcineurin inhibitor used to prevent organ transplant rejection and is effective in improving graft survival.However,it is linked to hyperglycemia and insulin resistance,contributing to new-onset diabetes after transplantation and negatively affecting islet function.AIM To study the effects of tacrolimus on the insulin signaling pathway of hepatocytes.METHODS HL7702 cells were treated with different concentrations of tacrolimus(0.1 mg/L,1 mg/L,5 mg/L)for 24 hours.The proteins involved in insulin signaling were detected by Western blotting.RESULTS Compared with the control group,phosphorylation of insulin receptor substrate(IRS)1 at Ser 307 and Ser 323 were increased significantly when the tacrolimus concentration reached 1 and 5 mg/L.Phosphorylation of IRS1 at Ser 1101 was also increased,although not significantly.However,phosphorylation of Ribosomal protein S6 kinase beta-1 at Thr 389 was decreased significantly.The levels of phosphorylated glycogen synthase kinase 3αSer 21 and Ser 9 were increased.Surprisingly,phosphorylation of glycogen synthase at Ser 641 was increased.There was no significant change in the activity of glycogen phosphorylase.CONCLUSION Tacrolimus has no direct effect on hepatic glucose metabolism,but inhibits IRS1-mediated insulin signaling.This may be one of the underlying mechanisms by which tacrolimus induces insulin resistance.展开更多
Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles...Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles in protein translation.The ribosomal subunit RPS6 has been studied for more than 50 years in various organisms,but little is known about its specific roles in certain signaling pathways.In this study,we focused on the functions of Arabidopsis RPS6A in auxin-related root growth and development.The rps6a mutant presented a series of auxin-deficient phenotypes,such as shortened primary roots,reduced lateral root numbers,and defective vasculatures.Treatment of the rps6a mutant with various concentrations of auxin and its analogs did not restore the root defect phenotypes,suggesting a defect in the auxin signaling pathway.Further cell biological and global transcriptome analyses revealed that auxin signaling was weakened in the rps6a mutant and that there was a reduced abundance of PIN-FORMED(PIN)auxin transporters.Our work provides insights into the role of the protein biosynthesis pathway involved in auxin signaling.展开更多
Objective The nucleolar protein PES1(Pescadillo homolog 1)plays critical roles in ribosome biogenesis and cell cycle regulation,yet its involvement in cellular senescence remains poorly understood.This study aimed to ...Objective The nucleolar protein PES1(Pescadillo homolog 1)plays critical roles in ribosome biogenesis and cell cycle regulation,yet its involvement in cellular senescence remains poorly understood.This study aimed to comprehensively investigate the functional consequences of PES1 suppression in cellular senescence and elucidate the molecular mechanisms underlying its regulatory role.Methods Initially,we assessed PES1 expression patterns in two distinct senescence models:replicative senescent mouse embryonic fibroblasts(MEFs)and doxorubicin-induced senescent human hepatocellular carcinoma HepG2 cells.Subsequently,PES1 expression was specifically downregulated using siRNA-mediated knockdown in these cell lines as well as additional relevant cell types.Cellular proliferation and senescence were assessed by EdU incorporation and SA-β-gal staining assays,respectively.The expression of senescence-associated proteins(p53,p21,and Rb)and SASP factors(IL-6,IL-1β,and IL-8)were analyzed by Western blot or qPCR.Furthermore,Northern blot and immunofluorescence were employed to evaluate pre-rRNA processing and nucleolar morphology.Results PES1 expression was significantly downregulated in senescent MEFs and HepG2 cells.PES1 knockdown resulted in decreased EdU-positive cells and increased SA-β-gal-positive cells,indicating proliferation inhibition and senescence induction.Mechanistically,PES1 suppression activated the p53-p21 pathway without affecting Rb expression,while upregulating IL-6,IL-1β,and IL-8 production.Notably,PES1 depletion impaired pre-rRNA maturation and induced nucleolar stress,as evidenced by aberrant nucleolar morphology.Conclusion Our findings demonstrate that PES1 deficiency triggers nucleolar stress and promotes p53-dependent(but Rb-independent)cellular senescence,highlighting its crucial role in maintaining nucleolar homeostasis and regulating senescence-associated pathways.展开更多
BACKGROUND In recent years,many studies have shown that proteasome 26S subunit non-ATPase 6(PSMD6)plays an important role in the occurrence and development of malignant tumours.Unfortunately,there are no reports on th...BACKGROUND In recent years,many studies have shown that proteasome 26S subunit non-ATPase 6(PSMD6)plays an important role in the occurrence and development of malignant tumours.Unfortunately,there are no reports on the evaluation of the potential role of PSMD6 in hepatocellular carcinoma(HCC).AIM To comprehensively evaluate the overexpression pattern and clinical significance of PSMD6 in HCC tissues.METHODS This study integrated PSMD6 mRNA expression profiles from 4672 HCC and 3667 non-HCC tissues,along with immunohistochemical scores from 383 HCC and adjacent tissues,to assess PSMD6 overexpression in HCC.Clustered regularly interspaced short palindromic repeats knockout technology evaluated PSMD6’s essential role in HCC cell growth.Functional enrichment analysis explored the molecular mechanism of PSMD6 abnormalities in HCC.Drug sensitivity analysis and molecular docking analysed the effect of abnormal expression of PSMD6 on the drug sensitivity of HCC cells.RESULTS The results of 41 external and two internal datasets showed that PSMD6 mRNA(SMD=0.26,95%CI:0.09-0.42,P<0.05)and protein(SMD=2.85,95%CI:1.19-4.50,P<0.05)were significantly overexpressed in HCC tissues.The integrated analysis results showed that PSMD6 had a significant overexpression pattern in HCC tissues(SMD=0.40,95%CI:0.15-0.66,P<0.05).PSMD6 knockout inhibited HCC cell growth(chronos scores<-1).Functional enrichment implicated ribosome biogenesis and RNA splicing.Significant enrichment of signalling pathways such as RNA degradation,ribosomes,and chemical carcinogenesis—reactive oxygen species.Drug sensitivity analysis and a molecular docking model showed that high expression of PSMD6 was associated with the tolerance of HCC cells to drugs such as ML323,sepantronium bromide,and GDC0810.Overexpressed PSMD6 effectively distinguished HCC tissues(AUC=0.75,95%CI:0.71-0.79).CONCLUSION This study was the first to discover that PSMD6 was overexpressed in HCC tissues.PSMD6 is essential for the growth of HCC cells and may be involved in ribosome biogenesis and RNA splicing.展开更多
Chaetoceros is a species-diverse genus of marine diatoms.The section Chaetoceros,recognized for the presence of numerous chloroplasts in both cell body and setae,is a common group of marine phytoplankton containing so...Chaetoceros is a species-diverse genus of marine diatoms.The section Chaetoceros,recognized for the presence of numerous chloroplasts in both cell body and setae,is a common group of marine phytoplankton containing some species,which may cause harm to marine organisms due to the robust setae.Modern taxonomic studies combining morphological and molecular data are still limited for the section Chaetoceros.To explore the diversity of the section Chaetoceros,monoclonal strains were established from the South China Sea and two novel species are described here,C.tetracarina sp.nov.and C.dicrinis sp.nov.Chaetoceros tetracarina is unique by the rimoportula on the anterior valve having four basal ridges supporting the external tube,whereas the other rimoportulae in the same chains or the one on the posterior valve for single cells each only possess a long external tube and lack basal ridges.Chaetoceros dicrinis is solitary and characterized by the symmetrical extending of the two setae on the same valve under light microscope(LM).The phylogenetic results show the presence of several groups within the section Chaetoceros.Chaetoceros tetracarina was sister to C.cf.pseudodichaeta,but differed by 33 and 46 bps in ribosomal large-subunit(LSU)and small-subunit(SSU)sequences respectively.The most closely-related species of C.dicrinis was C.denticulatus,but they were distinctly different morphologically,differing by 3 and 2 bps in LSU and SSU sequences respectively.This study provides new findings to understand the diversity of section Chaetoceros;however the inner relationships within this section remain largely unresolved.展开更多
Natural products play a crucial role in new drug development,but their druggability is often limited by uncertain molecular targets and insufficient research on mechanisms of action.In this study,we developed a new RP...Natural products play a crucial role in new drug development,but their druggability is often limited by uncertain molecular targets and insufficient research on mechanisms of action.In this study,we developed a new RPL19-TRAP^(KI)-seq method,combining CRISPR/Cas9 and TRAP technologies,to investigate these mechanisms.We identified and validated seven ribosomal large subunit surface proteins suitable for TRAP,selecting RPL19 for its high enrichment.We successfully established a stable cell line expressing EGFP-RPL19 using CRISPR knock-in and verified its efficiency and specificity in enriching ribosomes and translating mRNA.Integrated with next-generation sequencing,this method allows precise detection of translating mRNA.We validated RPL19-TRAP^(KI)-seq by investigating rapamycin,an mTOR inhibitor,yielding results consistent with previous reports.This optimized TRAP technology provides an accurate representation of translating mRNA,closely reflecting protein expression levels.Furthermore,we investigated SBF-1,a 23-oxa-analog of natural saponin OSW-1 with significant anti-tumor activity but an unclear mechanism.Using RPL19-TRAP^(KI)-seq,we found that SBF-1 exerts its cytotoxic effects on tumor cells by disturbing cellular oxidative phosphorylation.In conclusion,our method has been proven to be a promising tool that can reveal the mechanisms of small molecules with greater accuracy,setting the stage for future exploration of small molecules and advancing the fields of pharmacology and therapeutic development.展开更多
Commercial cultivars of garlic,a popular condiment,are sterile,making genetic variation and germplasm innovation of this plant challenging.Understanding mechanism of gamete sterility in garlic and their key regulatory...Commercial cultivars of garlic,a popular condiment,are sterile,making genetic variation and germplasm innovation of this plant challenging.Understanding mechanism of gamete sterility in garlic and their key regulatory networks is therefore important for fertility restoration.In this work,we conducted a detailed phenotypic analysis of fertile and sterile garlic genotypes and found that enlargement of topset in the inflorescence of sterile genotypes led to abnormal flowers.Additional cytological observations showed that aberrant meiotic cytokinesis in sterile garlic ultimately resulted in pollen degeneration.Transcriptomics analysis of sterile and fertile genotypes identified possible molecular mechanisms underlying gamete abortion.A total of 100710 differentially expressed genes(DEGs)between the fertile and sterile garlic flowers at three stages of gamete development were identified,many of which were involved in homologous chromosome synapsis during meiosis,MYB transcription factor regulation,ribosome biogenesis and plant hormone signal transduction.Taken together,these results provide insight into the molecular mechanisms and regulatory networks underlying gamete development in garlic and point to a set of candidate genes for further functional characterization.展开更多
Ribosome is an intracellular ribonucleoprotein particle that serves as the site of protein biosynthesis.Ribosomal dysfunction caused by mutations in genes encoding ribosomal proteins(RPs)and ribosome biogenesis factor...Ribosome is an intracellular ribonucleoprotein particle that serves as the site of protein biosynthesis.Ribosomal dysfunction caused by mutations in genes encoding ribosomal proteins(RPs)and ribosome biogenesis factors(RBFs)can lead to a spectrum of diseases,collectively known as ribosomopathy.Phase separation is a thermodynamic process that produces multiple phases from a homogeneous mixture.The formation of membraneless organelles and intracellular structures,including ribosomes and nucleoli,cannot occur without the involvement of phase separation.Here,ribosome structure,biogenesis,and their relationship with ribosomopathy are systematically reviewed.The tissue specificity of ribosomopathy and the role of phase separation in ribosomopathy are particularly discussed,which may offer some clues for understanding the mechanisms of ribosomopathy.Then,some new ideas for the prevention,diagnosis,and treatment of ribosomopathy are provided.展开更多
BACKGROUND The diagnosis of primary biliary cholangitis(PBC)remains challenging,particularly in cases where anti-mitochondrial antibody(AMA),anti-mitochondrial E2 subunit antibody(AMA-M2),anti-glycoprotein 210(anti-gp...BACKGROUND The diagnosis of primary biliary cholangitis(PBC)remains challenging,particularly in cases where anti-mitochondrial antibody(AMA),anti-mitochondrial E2 subunit antibody(AMA-M2),anti-glycoprotein 210(anti-gp210),and anti-speckled protein 100(anti-Sp100)are all negative.In such instances,the condition is often confirmed through a liver needle biopsy.AIM To identify additional plasma biomarkers for non-invasive diagnostic methods of PBC.METHODS We utilized the Sengenics KREX^(TM)immunome protein array to identify potential biomarkers for the diagnosis of PBC.Subsequently,we validated the predictive capability of the RPL30 antibody through an ELISA and retrospectively analyzed its association with the clinical features of 17 autoantibody-negative PBC cases and 45 autoantibody-positive PBC cases.RESULTS In our study we observed that RPL30 demonstrated the highest fold-change difference in PBC,with a penetrance frequency of 40%and a penetrance fold change of 38.30147.The analysis of anti-RPL30 optical density values between patients with AMA/AMA-M2/anti-gp210/anti-Sp100-negative PBC(autoantibody-negative PBC)and healthy controls using a receiver operating characteristic curve yielded an area under the curve of 0.853.This analysis established an optimal cutoff value of 0.0708,achieving 100%specificity and 75%sensitivity.The combination of anti-RPL30 and other autoantibodies elevated the diagnosis rate of PBC from 61.29%to 79.00%(P=0.0489).Anti-RPL30 demonstrated a high positive rate in antibody-negative PBC cases,including AMA/AMAM2/anti-gp210/anti-Sp100-negative cases.Correlation analysis of anti-RPL30 optical density values with clinical data from patients with PBC revealed a positive association with both the international normalized ratio(P=0.008)and the Model for End-Stage Liver Disease score(P=0.003).CONCLUSION Our study highlighted the potential of anti-RPL30 as a promising biomarker for diagnosing PBC,particularly in autoantibody-negative cases.展开更多
Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mu...Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mutant,tsa4,characterized by an albino phenotype at the seedling stage and abnormal chloroplast development at temperatures below 25℃.展开更多
Selenium is a crucial trace element that contributes to physiological processes in the body as selenoproteins.Selenoproteins serve as an integral role in the body in controlling the redox state of cells and protecting...Selenium is a crucial trace element that contributes to physiological processes in the body as selenoproteins.Selenoproteins serve as an integral role in the body in controlling the redox state of cells and protecting against damage induced by oxidative stress.This study aimed to investigate the effects and possible mechanism of selenium on selenoproteins expression in EA.hy926 cells induced by oxidized low density lipoprotein(oxLDL).The impact of selenium on the viability of EA.hy926 cells was detected by the methylthiazolyldiphenyltetrazolium bromide(MTT)method,and intracellular reactive oxygen species(ROS)level and mitochondrial membrane potential were assessed by fluorescent probe DCFH-DA and JC-1,respectively.RNA-seq,quantitative real-time polymerase chain reaction(qPCR),and Western blot were used to investigate the selenoprotein expression.Selenoprotein mRNA translation efficiency was analyzed by ribosome profiling(Ribo-Seq)coupled with transcriptomics.Our data showed that selenium supplementation(0.5μmol/L)significantly decreased ROS production,increased mitochondrial inner membrane potential and increased the proliferative activity of EA.hy926 cells induced by oxLDL.Moreover,The protective effects of selenium against oxLDL-induced EA.hy926 cell injury were associated with the upregulation of the expressions of selenoproteins glutathione peroxidase 1(GPX1),glutathione peroxidase 4(GPX4),and thioredoxin reductase 1(TXNRD1).Furthermore,the expressions of selenoproteins GPX1 and GPX4 were hierarchically controlled,but the expressions of selenoproteins TXNRD1 were mainly regulated by oxLDL.Finally,Ribo-Seq coupled with transcriptomics results demonstrated that the expressions of selenoproteins GPX1,GPX4,and TXNRD1 were regulated at the translation process level.These findings suggested that selenium could have preventive effects in oxLDL induced EA.hy926 cell injury by regulating the selenoprotein expression,and the selenoproteins expressions at the translation level in vascular endothelial cells need further study.展开更多
基金supported by funds from the National Natural Science Foundation of China (No. 31570754)Tsinghua-Peking Joint Center for Life Sciences and Beijing Advanced Innovation Center for Structural Biology to C. ChenLab Innovation Funding from Lab and Instrument Department, Tsinghua University to W. Wang
文摘Elongation factor 4（EF4） is one of the highly conserved translational GTPases, whose functions are largely unknown. Structures of EF4 bound ribosomal PRE-translocation and POST-translocation complexes have both been visualized. On top of cellular, structural, and biochemical studies, several controversial models have been raised to rationalize functions of EF4. However, how EF4 modulates elongation through its interactions with ribosomes has not been revealed. Here, using single-molecule fluorescence resonance energy transfer assays, we directly captured short-lived EF4·GTP bound ribosomal PRE and POST translocation complexes, which may adopt slightly different conformations from structures prepared using GDP, GDPNP, or GDPCP. Furthermore, we revealed that EF4·GTP severely impairs delivery of aminoacyl-tRNA into the A-site of the ribosome and moderately accelerates translocation. We proposed that functions of EF4 are to slow overall elongation and to stall majority of ribosomes in POST states under stress conditions.
文摘Ribosome-like particles have been found in the proplastids in young cotyledon cells of lotus (%Nelumbo nucifera Gaertn% L.). Following the development of young embryo, some lamellar structures and tubular complex occurred in the plastids in young cotyledon cells, and some ribosome-like particles appeared in the loose region of these membrane system and stroma. About 15- 20 d after fertilization, with the further development of plastid, a large number of starch and DNA were synthesized in the plastids, and the plastids contained abundant and clear morphologically ribosomes, some of which presented spiral structure. About 16-18 d after fertilization, amyloplasts were isolated and purified from cotyledon of lotus, and ribosomes bands were obtained by use of sucrose density gradient centrifugation of ribosomes isolated from amyloplasts. RNA and protein contents of ribosomes have also been determined.
基金partially supported by National Institute of Health(R21/R33-GM078601 and R01-GM100701)National Science Foundation(MCB-1151343)in the US
文摘Elucidating protein translational regulation is crucial for understanding cellular function and drug development.A key molecule in protein translation is ribosome,which is a super-molecular complex extensively studied for more than a half century.The structure and dynamics of ribosome complexes were resolved recently thanks to the development of X-ray crystallography,Cryo-EM,and single molecule biophysics.Current studies of the ribosome have shown multiple functional states,each with a unique conformation.In this study,we analyzed the RNA-protein distances of ribosome(2.5 MDa)complexes and compared these changes among different ribosome complexes.We found that the RNA-protein distance is significantly correlated with the ribosomal functional state.Thus,the analysis of RNA-protein binding distances at important functional sites can distinguish ribosomal functional states and help understand ribosome functions.In particular,the mechanism of translational attenuation by nascent peptides and antibiotics was revealed by the conformational changes of local functional sites.
基金This work was supported by grants from the National Natural Science Foundation of China(31788103 and 91540203 to X.Cao,31770874 to C.L.,31900932 to R.H.,and 31701096 to J.S.),Chinathe Strategic Priority Research Program of Chinese Academy of Sciences(XDB27030201 to X.Cao),China+1 种基金the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(QYZDY-SSW-SMC022 to X.Cao),Chinathe State Key Laboratory of Plant Genomics,China.
文摘Ribosome biogenesis,which takes place mainly in the nucleolus,involves coordinated expression of preribosomal RNAs(pre-rRNAs)and ribosomal proteins,pre-rRNA processing,and subunit assembly with the aid of numerous assembly factors.Our previous study showed that the Arabidopsis thaliana protein arginine methyltransferase AtPRMT3 regulates pre-rRNA processing;however,the underlying molecular mechanism remains unknown.Here,we report that AtPRMT3 interacts with Ribosomal Protein S2(RPS2),facilitating processing of the 90S/Small Subunit(SSU)processome and repressing nucleolar stress.We isolated an intragenic suppressor of atprmt3-2,which rescues the developmental defects of atprmt3-2 while produces a putative truncated AtPRMT3 protein bearing the entire N-terminus but lacking an intact enzymatic activity domain We further identified RPS2 as an interacting partner of AtPRMT3,and found that loss-of-function rps2a2b mutants were phenotypically reminiscent of atprmt3,showing pleiotropic developmental defects and aberrant pre-rRNA processing.RPS2B binds directly to pre-rRNAs in the nucleus,and such binding is enhanced in atprmt3-2.Consistently,multiple components of the 90S/SSU processome were more enriched by RPS2B in atprmt3-2,which accounts for early pre-rRNA processing defects and results in nucleolar stress.Collectively,our study uncovered a novel mechanism by which AtPRMT3 cooperates with RPS2B to facilitate the dynamic assembly/disassembly of the 90S/SSU processome during ribosome biogenesis and repress nucleolar stress.
基金Open Access funding enabled and organized by Projekt DEAL.Chunchu Deng was funded by PicoQuant and the Deutsche Forschungsgemeinschaft(DFG)Grant Se697/7-1,Project Number 405988308,DFG Grant JA1823/3-1 for SJ and Cure SMA for SJ,Grant JAB1920.PicoQuant did not influence project design,conduction of experiments or data analyses.
文摘Background:Axonal degeneration and defects in neuromuscular neurotransmission represent a pathological hall-mark in spinal muscular atrophy(SMA)and other forms of motoneuron disease.These pathological changes do not only base on altered axonal and presynaptic architecture,but also on alterations in dynamic movements of organelles and subcellular structures that are not necessarily reflected by static histopathological changes.The dynamic inter-play between the axonal endoplasmic reticulum(ER)and ribosomes is essential for stimulus-induced local translation in motor axons and presynaptic terminals.However,it remains enigmatic whether the ER and ribosome crosstalk is impaired in the presynaptic compartment of motoneurons with Smn(survival of motor neuron)deficiency that could contribute to axonopathy and presynaptic dysfunction in SMA.Methods:Using super-resolution microscopy,proximity ligation assay(PLA)and live imaging of cultured motoneu-rons from a mouse model of SMA,we investigated the dynamics of the axonal ER and ribosome distribution and activation.Results:We observed that the dynamic remodeling of ER was impaired in axon terminals of Smn-deficient motoneu-rons.In addition,in axon terminals of Smn-deficient motoneurons,ribosomes failed to respond to the brain-derived neurotrophic factor stimulation,and did not undergo rapid association with the axonal ER in response to extracellular stimuli.Conclusions:These findings implicate impaired dynamic interplay between the ribosomes and ER in axon terminals of motoneurons as a contributor to the pathophysiology of SMA and possibly also other motoneuron diseases.
基金supported by the National Natural Science Foundation of China(32270564 to P.Y.,82394422 to X.J.L.,82371178 to B.L.)Guangdong Basic and Applied Basic Research(2022A1515011205 and 2023A1515010811 to P.Y.,2021ZT09Y007 and 2018B030337001 to X.J.L.)。
文摘Cytoplasmic accumulation of TDP-43 is a pathological hallmark of amyotrophic lateral sclerosis(ALS)and other neurodegenerative diseases.While current studies have primarily focused on gene regulation mediated by full-length nuclear TDP-43,the potential effects of cytoplasmic TDP-43 fragments remain less explored.Our previous findings demonstrated that primate-specific cleavage of TDP-43 contributes to its cytoplasmic localization,prompting further investigation into its pathological effects.In the cynomolgus monkey brain,we observed that mutant or truncated TDP-43 was transported onto the ribosome organelle.Ribosome-associated transcriptomic analysis revealed dysregulation of apoptosis-and lysosome-related genes,indicating that cytoplasmic TDP-43 induces neurotoxicity by binding to ribosomes and disrupting mRNA expression.These findings provide mechanistic insights into the gain-of-function effects of pathological TDP-43.
基金Sanming Project of Medicine in Shenzhen:the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine,Luo Songping National Famous Chinese Medicine Practitioner Female Reproductive Disorders Prevention and Treatment Team(SZZYSM202311010)Guangdong Provincial Administration of Traditional Chinese Medicine:Investigation of the Mechanism of Regulating Ren-Tong-Du Acupuncture on Ovarian Granulosa Cells in Polycystic Ovary Syndrome based on Activin A/Smads Signalling Pathway(No.20181229)+1 种基金Guangdong Provincial Administration of Traditional Chinese Medicine:Evaluation of the Efficacy of Menstrual Regulation and Pregnancy Promotion by Acupuncture in the Treatment of Premature Ovarian Insufficiency(No.20201294)Shenzhen Science and Innovation Commission:Investigating the Mechanism of Action of Acupuncture in Regulating the Gut Microbiome to Inhibit Apoptosis of Ovarian Granulosa Cells in Premature Ovarian Insufficiency Mice based on the Rictor/Torepamycin Target Protein C2 Pathway(No.JCYJ20210324130001004)。
文摘PURPOSE:To investigate the differences in gut microbial characteristics between two traditional Chinese syndromes of premature ovarian insufficiency(POI).METHODS:Forty women with POI were recruited from the Department of Traditional Chinese Medicine at Shenzhen Maternity and Child Healthcare Hospital between June and December 2020.Women with POI were divided into the kidney deficiency and blood stasis syndrome(SDBS)and Qi and blood deficiency syndrome(QBDS)groups.Gut microbial community profiles were analyzed by 16S rRNA gene sequencing using an Illumina Mi Seq system.A retrospective study comparing hormone levels and gut microbiota information was performed between the SDBS and QBDS groups.RESULTS:Compared with the QBDS group,the serum levels of estradiol(E2)and anti-Müllerian hormone(AMH)were significantly decreased in the SDBS group.The quantities of Adlercreutzia,Eggerthella,Klebsiella,and Paraprevotella significantly increased in the SDBS group,whereas Lactobacillus decreased significantly.Moreover,alterations in the microbiome in the SDBS and QBDS groups were closely related to the levels of E2 and AMH.The area under the receiver operating characteristic curve for the classification of the two syndromes by the gut microbiome was 0.71.CONCLUSIONS:There were significant differences in the dominant microbiota between the SDBS and QBDS groups,and the change in Proteobacteria in the QBDS group was more significant.The characteristics of gut microbiota help us differentiate between the SDBS and QBDS groups,which may provide a basis for the objectification of TCM syndrome types.
基金Supported by the Jiaxing Science and Technology Project,No.2023AD11016 and No.2023AD31028.
文摘BACKGROUND Anal fistula is increasingly prevalent due to modern lifestyle factors,and surgery remains the primary treatment.However,the rising incidence of antibiotic resistance,particularly to cefuroxime,complicates perioperative management.The role of gut microbiota in influencing this resistance is not well understood.AIM To investigate the relationship between gut microbiota composition and cefuroxime resistance in anal fistula patients and to assess probiotic intervention impact.METHODS This study included 30 anal fistula patients categorized into cefuroxime-sensitive(Cefur-S)and cefuroxime-resistant(Cefur-NS)groups.Gut microbiota samples were collected during colonoscopy,and 16S ribosomal DNA sequencing was performed to analyze microbial diversity.Patients in the Cefur-NS group received a 7-day course of Clostridium butyricum tablets.Post-intervention,microbial composition and cefuroxime resistance were reassessed.RESULTS Alpha and beta diversity analyses showed no significant differences in microbial diversity between the Cefur-S and Cefur-NS groups.However,effect size analysis identified Roseburia and Butyricicoccus as dominant genera in the Cefur-S group,with higher butyrate production potentially protecting against cefuroxime resistance.Post-intervention,the Cefur-NS group showed a significant reduction in cefuroxime resistance,improved stool consistency,and reduced bowel movement frequency.CONCLUSION This study suggests that specific gut microbiota,particularly Butyricicoccus and Roseburia,may mitigate cefuroxime resistance in anal fistula patients by increasing butyrate production.Probiotic intervention targeting gut microbiota composition presents a promising strategy for reducing antibiotic resistance and improving clinical outcomes.
基金supported by the National Key Research and Development Program of China(No.2023YFA0916000)the National Natural Science Foundation of China(No.32371324)the High-level Talent Startup Fund provided by China Pharmaceutical University.
文摘Ribosomally synthesized and post-translationally modified peptides(RiPPs)constitute a vast and diverse family of bioactive peptides.These peptides,synthesized by ribosomes and subsequently modified by various tailoring enzymes,possess a wide chemical space.Among these modifications,radical S-adenosylmethionine(rSAM)enzymes employ unique radical chemistry to introduce a variety of novel peptide structures,which are crucial for their activity.This review examines the major types of modifications in RiPPs catalyzed by rSAM enzymes,incorporating recent advancements in protein structure analysis techniques and computational methods.Additionally,it elucidates the diverse catalytic mechanisms and substrate selectivity of these enzymes through an analysis of the latest crystal structures.
文摘BACKGROUND Tacrolimus(FK506)is a key calcineurin inhibitor used to prevent organ transplant rejection and is effective in improving graft survival.However,it is linked to hyperglycemia and insulin resistance,contributing to new-onset diabetes after transplantation and negatively affecting islet function.AIM To study the effects of tacrolimus on the insulin signaling pathway of hepatocytes.METHODS HL7702 cells were treated with different concentrations of tacrolimus(0.1 mg/L,1 mg/L,5 mg/L)for 24 hours.The proteins involved in insulin signaling were detected by Western blotting.RESULTS Compared with the control group,phosphorylation of insulin receptor substrate(IRS)1 at Ser 307 and Ser 323 were increased significantly when the tacrolimus concentration reached 1 and 5 mg/L.Phosphorylation of IRS1 at Ser 1101 was also increased,although not significantly.However,phosphorylation of Ribosomal protein S6 kinase beta-1 at Thr 389 was decreased significantly.The levels of phosphorylated glycogen synthase kinase 3αSer 21 and Ser 9 were increased.Surprisingly,phosphorylation of glycogen synthase at Ser 641 was increased.There was no significant change in the activity of glycogen phosphorylase.CONCLUSION Tacrolimus has no direct effect on hepatic glucose metabolism,but inhibits IRS1-mediated insulin signaling.This may be one of the underlying mechanisms by which tacrolimus induces insulin resistance.
基金supported by the National Natural Science Foundation of China(32321001)the Forestry Bureau of Anhui Province(AHLYJBGS-2024-01)+3 种基金the Center for Advanced Interdisciplinary Science and Biomedicine of IHM,the Division of Life Sciences and Medicine,the University of Science and Technology of China(QYPY20220012)the USTC Research Funds of the Double First-Class Initiative(YD9100002016)start-up funding from the University of Science and Technology of China and the Chinese Academy of Sciences(GG9100007007,KY9100000026,KY9100000051,KJ2070000079)the Fundamental Research Funds for the Central Universities(WK9100000021)。
文摘Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles in protein translation.The ribosomal subunit RPS6 has been studied for more than 50 years in various organisms,but little is known about its specific roles in certain signaling pathways.In this study,we focused on the functions of Arabidopsis RPS6A in auxin-related root growth and development.The rps6a mutant presented a series of auxin-deficient phenotypes,such as shortened primary roots,reduced lateral root numbers,and defective vasculatures.Treatment of the rps6a mutant with various concentrations of auxin and its analogs did not restore the root defect phenotypes,suggesting a defect in the auxin signaling pathway.Further cell biological and global transcriptome analyses revealed that auxin signaling was weakened in the rps6a mutant and that there was a reduced abundance of PIN-FORMED(PIN)auxin transporters.Our work provides insights into the role of the protein biosynthesis pathway involved in auxin signaling.
文摘Objective The nucleolar protein PES1(Pescadillo homolog 1)plays critical roles in ribosome biogenesis and cell cycle regulation,yet its involvement in cellular senescence remains poorly understood.This study aimed to comprehensively investigate the functional consequences of PES1 suppression in cellular senescence and elucidate the molecular mechanisms underlying its regulatory role.Methods Initially,we assessed PES1 expression patterns in two distinct senescence models:replicative senescent mouse embryonic fibroblasts(MEFs)and doxorubicin-induced senescent human hepatocellular carcinoma HepG2 cells.Subsequently,PES1 expression was specifically downregulated using siRNA-mediated knockdown in these cell lines as well as additional relevant cell types.Cellular proliferation and senescence were assessed by EdU incorporation and SA-β-gal staining assays,respectively.The expression of senescence-associated proteins(p53,p21,and Rb)and SASP factors(IL-6,IL-1β,and IL-8)were analyzed by Western blot or qPCR.Furthermore,Northern blot and immunofluorescence were employed to evaluate pre-rRNA processing and nucleolar morphology.Results PES1 expression was significantly downregulated in senescent MEFs and HepG2 cells.PES1 knockdown resulted in decreased EdU-positive cells and increased SA-β-gal-positive cells,indicating proliferation inhibition and senescence induction.Mechanistically,PES1 suppression activated the p53-p21 pathway without affecting Rb expression,while upregulating IL-6,IL-1β,and IL-8 production.Notably,PES1 depletion impaired pre-rRNA maturation and induced nucleolar stress,as evidenced by aberrant nucleolar morphology.Conclusion Our findings demonstrate that PES1 deficiency triggers nucleolar stress and promotes p53-dependent(but Rb-independent)cellular senescence,highlighting its crucial role in maintaining nucleolar homeostasis and regulating senescence-associated pathways.
基金Supported by National Natural Science Foundation of China,No.82160762Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine Scientific Research Project,No.GXZYA20230267+2 种基金China Undergraduate Innovation and Entrepreneurship Training Program,No.S202410598060XChina Undergraduate Innovation and Entrepreneurship Training Program,No.X202410598360Future Academic Star of Guangxi Medical University,No.WLXSZX24074.
文摘BACKGROUND In recent years,many studies have shown that proteasome 26S subunit non-ATPase 6(PSMD6)plays an important role in the occurrence and development of malignant tumours.Unfortunately,there are no reports on the evaluation of the potential role of PSMD6 in hepatocellular carcinoma(HCC).AIM To comprehensively evaluate the overexpression pattern and clinical significance of PSMD6 in HCC tissues.METHODS This study integrated PSMD6 mRNA expression profiles from 4672 HCC and 3667 non-HCC tissues,along with immunohistochemical scores from 383 HCC and adjacent tissues,to assess PSMD6 overexpression in HCC.Clustered regularly interspaced short palindromic repeats knockout technology evaluated PSMD6’s essential role in HCC cell growth.Functional enrichment analysis explored the molecular mechanism of PSMD6 abnormalities in HCC.Drug sensitivity analysis and molecular docking analysed the effect of abnormal expression of PSMD6 on the drug sensitivity of HCC cells.RESULTS The results of 41 external and two internal datasets showed that PSMD6 mRNA(SMD=0.26,95%CI:0.09-0.42,P<0.05)and protein(SMD=2.85,95%CI:1.19-4.50,P<0.05)were significantly overexpressed in HCC tissues.The integrated analysis results showed that PSMD6 had a significant overexpression pattern in HCC tissues(SMD=0.40,95%CI:0.15-0.66,P<0.05).PSMD6 knockout inhibited HCC cell growth(chronos scores<-1).Functional enrichment implicated ribosome biogenesis and RNA splicing.Significant enrichment of signalling pathways such as RNA degradation,ribosomes,and chemical carcinogenesis—reactive oxygen species.Drug sensitivity analysis and a molecular docking model showed that high expression of PSMD6 was associated with the tolerance of HCC cells to drugs such as ML323,sepantronium bromide,and GDC0810.Overexpressed PSMD6 effectively distinguished HCC tissues(AUC=0.75,95%CI:0.71-0.79).CONCLUSION This study was the first to discover that PSMD6 was overexpressed in HCC tissues.PSMD6 is essential for the growth of HCC cells and may be involved in ribosome biogenesis and RNA splicing.
基金Supported by the National Key Research and Development Program of China(No.2022 YFC 3105201)the National Natural Science Foundation of China(No.32170206)the Joint Fund of National Natural Science Foundation of China and NSFC-Shandong Joint Key Project(No.U 2106205)。
文摘Chaetoceros is a species-diverse genus of marine diatoms.The section Chaetoceros,recognized for the presence of numerous chloroplasts in both cell body and setae,is a common group of marine phytoplankton containing some species,which may cause harm to marine organisms due to the robust setae.Modern taxonomic studies combining morphological and molecular data are still limited for the section Chaetoceros.To explore the diversity of the section Chaetoceros,monoclonal strains were established from the South China Sea and two novel species are described here,C.tetracarina sp.nov.and C.dicrinis sp.nov.Chaetoceros tetracarina is unique by the rimoportula on the anterior valve having four basal ridges supporting the external tube,whereas the other rimoportulae in the same chains or the one on the posterior valve for single cells each only possess a long external tube and lack basal ridges.Chaetoceros dicrinis is solitary and characterized by the symmetrical extending of the two setae on the same valve under light microscope(LM).The phylogenetic results show the presence of several groups within the section Chaetoceros.Chaetoceros tetracarina was sister to C.cf.pseudodichaeta,but differed by 33 and 46 bps in ribosomal large-subunit(LSU)and small-subunit(SSU)sequences respectively.The most closely-related species of C.dicrinis was C.denticulatus,but they were distinctly different morphologically,differing by 3 and 2 bps in LSU and SSU sequences respectively.This study provides new findings to understand the diversity of section Chaetoceros;however the inner relationships within this section remain largely unresolved.
基金supported by the National Key Research and Development Program of China(No.2022YFC2804800 to W.J.)the National Natural Science Foundation of China(No.22494704.,22137002 to Y.D.,92253305 to W.J.and 31971111 to C.L.)+6 种基金the Science and Technology Commission of Shanghai Municipality(Grant 20JC1410900 to Y.D.)the University Innovation Research Group in Chongqing(No.CXQT21016 to Y.D.)the Chongqing Talent Program Project(No.CQYC20200302119 to Y.D.)High-Level Innovation Platform Cultivation Plan of Chongqing(to Y.D.)Joint Fund of the Natural Science Innovation and Development Foundation of Chongqing(to Y.D.)Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(to W.J.)Chongqing Doctoral Express Entry Project(No.CSTB2022BSXM-JCX0044 to J.H.).
文摘Natural products play a crucial role in new drug development,but their druggability is often limited by uncertain molecular targets and insufficient research on mechanisms of action.In this study,we developed a new RPL19-TRAP^(KI)-seq method,combining CRISPR/Cas9 and TRAP technologies,to investigate these mechanisms.We identified and validated seven ribosomal large subunit surface proteins suitable for TRAP,selecting RPL19 for its high enrichment.We successfully established a stable cell line expressing EGFP-RPL19 using CRISPR knock-in and verified its efficiency and specificity in enriching ribosomes and translating mRNA.Integrated with next-generation sequencing,this method allows precise detection of translating mRNA.We validated RPL19-TRAP^(KI)-seq by investigating rapamycin,an mTOR inhibitor,yielding results consistent with previous reports.This optimized TRAP technology provides an accurate representation of translating mRNA,closely reflecting protein expression levels.Furthermore,we investigated SBF-1,a 23-oxa-analog of natural saponin OSW-1 with significant anti-tumor activity but an unclear mechanism.Using RPL19-TRAP^(KI)-seq,we found that SBF-1 exerts its cytotoxic effects on tumor cells by disturbing cellular oxidative phosphorylation.In conclusion,our method has been proven to be a promising tool that can reveal the mechanisms of small molecules with greater accuracy,setting the stage for future exploration of small molecules and advancing the fields of pharmacology and therapeutic development.
基金supported by the National Characteristic Vegetable Industry Technology System of China(Grant No.CARS24-A-07)the Jiangsu Modern Agricultural Industry Technology System Construction Special Fund(Grant No.JATS[2023]050)Xuzhou Academy of Agricultural Sciences Research Fund Project(Grant No.XM2021003)。
文摘Commercial cultivars of garlic,a popular condiment,are sterile,making genetic variation and germplasm innovation of this plant challenging.Understanding mechanism of gamete sterility in garlic and their key regulatory networks is therefore important for fertility restoration.In this work,we conducted a detailed phenotypic analysis of fertile and sterile garlic genotypes and found that enlargement of topset in the inflorescence of sterile genotypes led to abnormal flowers.Additional cytological observations showed that aberrant meiotic cytokinesis in sterile garlic ultimately resulted in pollen degeneration.Transcriptomics analysis of sterile and fertile genotypes identified possible molecular mechanisms underlying gamete abortion.A total of 100710 differentially expressed genes(DEGs)between the fertile and sterile garlic flowers at three stages of gamete development were identified,many of which were involved in homologous chromosome synapsis during meiosis,MYB transcription factor regulation,ribosome biogenesis and plant hormone signal transduction.Taken together,these results provide insight into the molecular mechanisms and regulatory networks underlying gamete development in garlic and point to a set of candidate genes for further functional characterization.
基金supported by the National Natural Science Foundation of China(Nos.82071097 and 82370906)the Shanghai Pujiang Program(No.2020PJD026)+1 种基金the Key Laboratory of Oral Biomedical Research of Zhejiang Province Foundation(No.2021M007)the Research Project of Shanghai Municipal Health Commission(No.20234Z0006),China.
文摘Ribosome is an intracellular ribonucleoprotein particle that serves as the site of protein biosynthesis.Ribosomal dysfunction caused by mutations in genes encoding ribosomal proteins(RPs)and ribosome biogenesis factors(RBFs)can lead to a spectrum of diseases,collectively known as ribosomopathy.Phase separation is a thermodynamic process that produces multiple phases from a homogeneous mixture.The formation of membraneless organelles and intracellular structures,including ribosomes and nucleoli,cannot occur without the involvement of phase separation.Here,ribosome structure,biogenesis,and their relationship with ribosomopathy are systematically reviewed.The tissue specificity of ribosomopathy and the role of phase separation in ribosomopathy are particularly discussed,which may offer some clues for understanding the mechanisms of ribosomopathy.Then,some new ideas for the prevention,diagnosis,and treatment of ribosomopathy are provided.
基金Supported by National Natural Science Foundation of China,No.82172257Health Care Major Project of Guangzhou,No.202206080001Science and Technology Cooperation Program of Fujian Province,No.2021I0036。
文摘BACKGROUND The diagnosis of primary biliary cholangitis(PBC)remains challenging,particularly in cases where anti-mitochondrial antibody(AMA),anti-mitochondrial E2 subunit antibody(AMA-M2),anti-glycoprotein 210(anti-gp210),and anti-speckled protein 100(anti-Sp100)are all negative.In such instances,the condition is often confirmed through a liver needle biopsy.AIM To identify additional plasma biomarkers for non-invasive diagnostic methods of PBC.METHODS We utilized the Sengenics KREX^(TM)immunome protein array to identify potential biomarkers for the diagnosis of PBC.Subsequently,we validated the predictive capability of the RPL30 antibody through an ELISA and retrospectively analyzed its association with the clinical features of 17 autoantibody-negative PBC cases and 45 autoantibody-positive PBC cases.RESULTS In our study we observed that RPL30 demonstrated the highest fold-change difference in PBC,with a penetrance frequency of 40%and a penetrance fold change of 38.30147.The analysis of anti-RPL30 optical density values between patients with AMA/AMA-M2/anti-gp210/anti-Sp100-negative PBC(autoantibody-negative PBC)and healthy controls using a receiver operating characteristic curve yielded an area under the curve of 0.853.This analysis established an optimal cutoff value of 0.0708,achieving 100%specificity and 75%sensitivity.The combination of anti-RPL30 and other autoantibodies elevated the diagnosis rate of PBC from 61.29%to 79.00%(P=0.0489).Anti-RPL30 demonstrated a high positive rate in antibody-negative PBC cases,including AMA/AMAM2/anti-gp210/anti-Sp100-negative cases.Correlation analysis of anti-RPL30 optical density values with clinical data from patients with PBC revealed a positive association with both the international normalized ratio(P=0.008)and the Model for End-Stage Liver Disease score(P=0.003).CONCLUSION Our study highlighted the potential of anti-RPL30 as a promising biomarker for diagnosing PBC,particularly in autoantibody-negative cases.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.32341026 and 32171998)the Hunan Provincial Science and Technology Innovation Program,China(Grant No.2023NK1010)the Changsha Natural Science Foundation,China(Grant No.20209001).
文摘Leaf color mutants (LCMs) provide crucial insights into the regulatory mechanisms underlying chloroplast development,photo synthesis,and stre ss adaptation.In this study,we identified a temperature-sensitive albino mutant,tsa4,characterized by an albino phenotype at the seedling stage and abnormal chloroplast development at temperatures below 25℃.
基金supported by grants from the National Natural Science Foundation of China(NSFC,81960588)the Ningxia Natural Science Foundation(2020AAC03146)support from the Ningxia Medical University。
文摘Selenium is a crucial trace element that contributes to physiological processes in the body as selenoproteins.Selenoproteins serve as an integral role in the body in controlling the redox state of cells and protecting against damage induced by oxidative stress.This study aimed to investigate the effects and possible mechanism of selenium on selenoproteins expression in EA.hy926 cells induced by oxidized low density lipoprotein(oxLDL).The impact of selenium on the viability of EA.hy926 cells was detected by the methylthiazolyldiphenyltetrazolium bromide(MTT)method,and intracellular reactive oxygen species(ROS)level and mitochondrial membrane potential were assessed by fluorescent probe DCFH-DA and JC-1,respectively.RNA-seq,quantitative real-time polymerase chain reaction(qPCR),and Western blot were used to investigate the selenoprotein expression.Selenoprotein mRNA translation efficiency was analyzed by ribosome profiling(Ribo-Seq)coupled with transcriptomics.Our data showed that selenium supplementation(0.5μmol/L)significantly decreased ROS production,increased mitochondrial inner membrane potential and increased the proliferative activity of EA.hy926 cells induced by oxLDL.Moreover,The protective effects of selenium against oxLDL-induced EA.hy926 cell injury were associated with the upregulation of the expressions of selenoproteins glutathione peroxidase 1(GPX1),glutathione peroxidase 4(GPX4),and thioredoxin reductase 1(TXNRD1).Furthermore,the expressions of selenoproteins GPX1 and GPX4 were hierarchically controlled,but the expressions of selenoproteins TXNRD1 were mainly regulated by oxLDL.Finally,Ribo-Seq coupled with transcriptomics results demonstrated that the expressions of selenoproteins GPX1,GPX4,and TXNRD1 were regulated at the translation process level.These findings suggested that selenium could have preventive effects in oxLDL induced EA.hy926 cell injury by regulating the selenoprotein expression,and the selenoproteins expressions at the translation level in vascular endothelial cells need further study.
