Spermatozoa have a highly complex RNA profile.Several of these transcripts are suggested as biomarkers for male infertility and contribute to early development.To analyze the differences between sperm RNA quantity and...Spermatozoa have a highly complex RNA profile.Several of these transcripts are suggested as biomarkers for male infertility and contribute to early development.To analyze the differences between sperm RNA quantity and expression of protamine(PRM1 and PRM2)and testis-specific histone 2B(TH2B)genes,spermatozoa from 33 patients who enrolled in assisted reproduction treatment(ART)program were analyzed.Sperm RNA of teratozoospermic(T),oligoteratozoospermic(OT),and normozoospermic(N)samples was extracted,and the differences in transcript levels among the study groups were analyzed by quantitative real-time polymerase chain reaction(qRT-PCR).The correlations of total RNA per spermatozoon and the expression of the transcripts were evaluated in relation to sperm characteristics and preimplantation embryo development.The mean(±standard deviation)RNA amount per spermatozoon was 28.48(±23.03)femtogram in the overall group and was significantly higher in the OT group than that in N and T groups.Total sperm RNA and gene expression of PRM1 and PRM2 genes were related to preimplantation embryo development and developmental arrest.Specific sperm characteristics were correlated with the expressions of PRM1,PRM2,or TH2B genes.We conclude that the sperm RNA amount and composition are important factors and might influence early embryonic development and also differ in different cases of male infertility.展开更多
The oviduct epithelium is the initial maternal contact site for embryos after fertilization,offering the microenviron-ment before implantation.This early gestation period is particularly sensitive to stress,which can ...The oviduct epithelium is the initial maternal contact site for embryos after fertilization,offering the microenviron-ment before implantation.This early gestation period is particularly sensitive to stress,which can cause reduced fertil-ity and reproductive disorders in mammals.Nevertheless,the local impact of elevated stress hormones on the ovi-duct epithelium has received limited attention to date,except for a few reports on polyovulatory species like mice and pigs.In this study,we focused on the effects of chronic maternal stress on cattle,given its association with infertil-ity issues in this monoovulatory species.Bovine oviduct epithelial cells(BOEC)differentiated at the air–liquid interface(ALI)were stimulated with 250 nmol/L cortisol for 1 or 3 weeks.Subsequently,they were assessed for morphology,bioelectrical properties,and gene expression related to oviduct function,glucocorticoid pathway,cortisol metabo-lism,inflammation,and apoptosis.Results revealed adverse effects of cortisol on epithelium structure,featured by deciliation,vacuole formation,and multilayering.Additionally,cortisol exposure led to an increase in transepithelial potential difference,downregulated mRNA expression of the major glucocorticoid receptor(NR3C1),upregulated the expression of cortisol-responsive genes(FKBP5,TSC22D3),and significant downregulation of oviductal glycopro-tein 1(OVGP1)and steroid receptors PGR and ESR1.The systematic comparison to a similar experiment previously performed by us in porcine oviduct epithelial cells,indicated that bovine cultures were more susceptible to elevated cortisol levels than porcine.The distinct responses between both species are likely linked to their divergence in the cortisol-induced expression changes of HSD11B2,an enzyme controlling the cellular capacity to metabolise cortisol.These findings provide insights into the species-specific reactions and reproductive consequences triggered by maternal stress.展开更多
Following the publication of Xu et al.(2022),an error was identified in Figure 1D.Specifically,the top left panel was inadvertently duplicated during figure preparation.To ensure the accuracy and integrity of our publ...Following the publication of Xu et al.(2022),an error was identified in Figure 1D.Specifically,the top left panel was inadvertently duplicated during figure preparation.To ensure the accuracy and integrity of our published work,we request the publication of a corrigendum with the corrected image.We apologize for this oversight and any confusion it may have caused.The amended figure is provided in the updated Supplementary Materials.展开更多
Human cytomegalovirus(HCMV)poses a significant risk of neural damage during pregnancy.As the most prevalent intrauterine infectious agent in low-and middle-income countries,HCMV disrupts the development of neural stem...Human cytomegalovirus(HCMV)poses a significant risk of neural damage during pregnancy.As the most prevalent intrauterine infectious agent in low-and middle-income countries,HCMV disrupts the development of neural stem cells,leading to fetal malformations and abnormal structural and physiological functions in the fetal brain.This review summarizes the current understanding of how HCMV infection dysregulates the Wnt signaling pathway to induce fetal malformations and discusses current management strategies.展开更多
Spatial transcriptomics technology provides novel insights into the spatial organization of gene expression during embryonic development.In this study,we propose a method that integrates analysis across both temporal ...Spatial transcriptomics technology provides novel insights into the spatial organization of gene expression during embryonic development.In this study,we propose a method that integrates analysis across both temporal and spatial dimensions to investigate spatial transcriptomics data from mouse embryos at different developmental stages.We quantified the spatial expression pattern of each gene at various stages by calculating its Moran’s I.Furthermore,by employing time-series clustering to identify dynamic co-expression modules,we identified several developmentally stage-specific regulatory gene modules.A key finding was the presence of distinct,stage-specific gene network modules across different developmental periods:Early modules focused on morphogenesis,mid-stage on organ development,and late-stage on neural and tissue maturation.Functional enrichment analysis further confirmed the core biological functions of each module.The dynamic,spatially-resolved gene expression model constructed in this study not only provides new biological insights into the programmed spatiotemporal reorganization of gene regulatory networks during embryonic development but also presents an effective approach for analyzing complex spatiotemporal omics data.This work provides a new perspective for understanding developmental biology,regenerative medicine,and related fields.展开更多
Periodontitis is a common oral disease caused by bacteria coupled with an excessive host immune response.Stem cell therapy can be a promising treatment strategy for periodontitis,but the relevant mechanism is complica...Periodontitis is a common oral disease caused by bacteria coupled with an excessive host immune response.Stem cell therapy can be a promising treatment strategy for periodontitis,but the relevant mechanism is complicated.This study aimed to explore the therapeutic potential of mitochondria from human embryonic stem cell-derived mesenchymal stem cells(hESC-MSCs)for the treatment of periodontitis.The gingival tissues of periodontitis patients are characterized by abnormal mitochondrial structure.Human gingival fibroblasts(HGFs)were exposed to 5μg/mL lipopolysaccharide(LPS)for 24 h to establish a cell injury model.When treated with hESC-MSCs or mitochondria derived from hESC-MSCs,HGFs showed reduced expression of inflammatory genes,increased adenosine triphosphate(ATP)level,decreased reactive oxygen species(ROS)production,and enhanced mitochondrial function compared to the control.The average efficiency of isolated mitochondrial transfer by hESC-MSCs was determined to be 8.93%.Besides,a therapy of local mitochondrial injection in mice with LPS-induced periodontitis showed a reduction in inflammatory gene expression,as well as an increase in both the mitochondrial number and the aspect ratio in gingival tissues.In conclusion,our results indicate that mitochondria derived from hESC-MSCs can reduce the inflammatory response and improve mitochondrial function in HGFs,suggesting that the transfer of mitochondria between hESC-MSCs and HGFs serves as a potential mechanism underlying the therapeutic effect of stem cells.展开更多
More and more studies have demonstrated that pseudogenes possess coding ability,and the functions of their transcripts in the development of diseases have been partially revealed.However,the role of pseudogenes in mai...More and more studies have demonstrated that pseudogenes possess coding ability,and the functions of their transcripts in the development of diseases have been partially revealed.However,the role of pseudogenes in maintenance of normal physiological states and life activities has long been neglected.Here,we identify pseudogenes that are dynamically expressed during human early embryogenesis,showing different expression patterns from that of adult tissues.We explore the expression correlation between pseudogenes and the parent genes,partly due to their shared gene regulatory elements or the potential regulation network between them.The essential role of three pseudogenes,PI4KAP1,TMED10P1,and FBXW4P1,in maintaining self-renewal of human embryonic stem cells is demonstrated.We further find that the three pseudogenes might perform their regulatory functions by binding to proteins or microRNAs.The pseudogene-related single-nucleotide polymorphisms are significantly associated with human congenital disease,further illustrating their importance during early embryonic development.Overall,this study is an excavation and exploration of functional pseudogenes during early human embryonic development,suggesting that pseudogenes are not only capable of being specifically activated in pathological states,but also play crucial roles in the maintenance of normal physiological states.展开更多
In recent years,neonicotinoids(NEOs)and organophosphate esters(OPEs)have been widely used as substitutes for traditional pesticides and brominated fame-retardants,respectively.Previous studies have shown that those co...In recent years,neonicotinoids(NEOs)and organophosphate esters(OPEs)have been widely used as substitutes for traditional pesticides and brominated fame-retardants,respectively.Previous studies have shown that those compounds can be frequently detected in environmental and human samples,are able to penetrate the placental barrier,and are toxic to animals.Thus,it is reasonable to speculate that NEOs and OPEs may have potential adverse effects in humans,especially during development.We employed a human embryonic stem cell differentiation-and liver S9 fraction metabolism-based fast screening model to assess the potential embryonic toxicity of those two types of chemicals.We show that four NEO and five OPE prototypes targeted mostly ectoderm specification,as neural ectoderm and neural crest genes were down-regulated,and surface ectoderm and placode markers up-regulated.Human liver S9 fraction's treatment could generally reduce the effects of the chemicals,except in a few specific instances,indicating the liver may detoxify NEOs and OPEs.Our findings suggest that NEOs and OPEs interfere with human early embryonic development.展开更多
BACKGROUND This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure....BACKGROUND This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure.CASE SUMMARY Here,we collected and described the clinical data of a patient with early embryonic development stagnation after repeated in vitro fertilization attempts for primary infertility at the Department Reproductive Center of Zaozhuang Maternal and Child Healthcare Hospital.We also detected the whole-exon gene of the patient's spouse and parents,and conducted bioinformatics analysis to determine the pathogenesis of the gene.CONCLUSION A novel mutant of the TUBB8 gene[c.602G>T(p.C201F)]was identified,and this mutant provided new data on the genotype-phenotype relationships of related diseases.展开更多
Genetic transformation has been an effective technology for improving the agronomic traits of maize.However,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype dependence.In this study,...Genetic transformation has been an effective technology for improving the agronomic traits of maize.However,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype dependence.In this study,we performed genomic sequencing for 80 core maize germplasms and constructed a high-density genomic variation map using our newly developed pipeline(MQ2Gpipe).Based on the induction rate of EC(REC),these inbred lines were categorized into three subpopulations.The low-REC germplasms displayed more abundant genetic diversity than the high-REC germplasms.By integrating a genome-wide selective signature screen and region-based association analysis,we revealed 95.23 Mb of selective regions and 43 REC-associated variants.These variants had phenotypic variance explained values ranging between 21.46 and 49.46%.In total,103 candidate genes were identified within the linkage disequilibrium regions of these REC-associated loci.These genes mainly participate in regulation of the cell cycle,regulation of cytokinesis,and other functions,among which MYB15 and EMB2745 were located within the previously reported QTL for EC induction.Numerous leaf area-associated variants with large effects were closely linked to several REC-related loci,implying a potential synergistic selection of REC and leaf size during modern maize breeding.展开更多
Regulation of cell fate requires the establishment and erasure of 5-methylcytosine(5mC) in genomic DNA.The formation of 5mC is achieved by DNA cytosine methyltransferases(DNMTs),whereas the removal of5mC can be accomp...Regulation of cell fate requires the establishment and erasure of 5-methylcytosine(5mC) in genomic DNA.The formation of 5mC is achieved by DNA cytosine methyltransferases(DNMTs),whereas the removal of5mC can be accomplished by various pathways.Aside from ten-eleven translocation(TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase(TDG)-initiated base excision repair(BER),the direct deformylation of 5-formylcytosine(5fC) and decarboxylation of 5-carboxylcytosine(5caC) have also been discovered as the novel DNA demethylation pathways.Although these novel demethylation pathways have been identified in stem cells and somatic cells,their precise roles in regulating cell fate remain unclear.Here,we differentiate mouse embryonic stem cells(mESCs) into mouse embryoid bodies(mEBs),followed by further differentiation into mouse neural stem cells(mNSCs) and finally into mouse neurons(mNeurons).During this sequential differentiation process,we employ probe molecules,namely2'-fluorinated 5-formylcytidine(F-5fC) and 2'-fluorinated 5-carboxyldeoxycytidine(F-5caC),for metabolic labeling.The results of mass spectrometry(MS) analysis demonstrate the deformylation and decarboxylation activities are progressively decreased and increased respectively during differentiation process,and this opposite demethylation tendency is not associated with DNMTs and TETs.展开更多
Investigating the development toxicity of perfuorinated iodine alkanes(PFIs)is critical,given their estrogenic effects through binding with estrogen receptors(ERs).In the present study,two PFIs,including dodecafuoro-1...Investigating the development toxicity of perfuorinated iodine alkanes(PFIs)is critical,given their estrogenic effects through binding with estrogen receptors(ERs).In the present study,two PFIs,including dodecafuoro-1,6-diiodohexane(PFHx DI)and tridecafuorohexyl iodide(PFHx I),with binding preference to ERαand ERβ,respectively,were selected to evaluate their effects on proliferation and differentiation of the mouse embryonic stem cells(m ESCs).The results revealed that,similar to E_(2),50μmol/L PFHx DI accelerated the cell proliferation of the m ESCs.The PFI stimulation at the exposure concentrations of 2–50μmol/L promoted the differentiation of the m ESCs as characterized by the upregulation of differentiation-related biomarkers(i.e.,Otx2 and Dnmt3β)and downregulation of pluripotency genes(i.e.,Oct4,Nanog,Sox2,Prdm14 and Rex1).Comparatively,PFHx DI exhibited higher induction effect on the differentiation of the m ESCs than did PFHx I.The tests on ER signaling indicated that both PFI compounds induced exposure concentration-dependent expressions of ER signaling-related biomarkers(i.e.,ERα,ERβand Caveolin-1)in the m ESCs,and the downstream ER responsive genes(i.e.,c-fos,c-myc and c-jun)well responded to PFHx I stimulation.The role of ER in PFI-induced effects on the m ESCs was further validated by the antagonistic experiments using an ER inhibitor(ICI).The findings demonstrated that PFIs triggered ER signaling,and perturbed the differentiation program of the m ESCs,causing the potential health risk during early stage of development.展开更多
Isocitrate dehydrogenase 2(IDH2)and glutamate dehydrogenase 1(GLUD1)are key enzymes involved in the production ofα-ketoglutarate(α-KG),a metabolite central to the tricarboxylic acid cycle and glutamine metabolism.In...Isocitrate dehydrogenase 2(IDH2)and glutamate dehydrogenase 1(GLUD1)are key enzymes involved in the production ofα-ketoglutarate(α-KG),a metabolite central to the tricarboxylic acid cycle and glutamine metabolism.In this study,we investigated the impact of IDH2 and GLUD1 on early porcine embryonic development following IDH2 and GLUD1 knockdown(KD)via doublestranded RNA(dsRNA)microinjection.Results showed that KD reducedα-KG levels,leading to delayed embryonic development,decreased blastocyst formation,increased apoptosis,reduced blastomere proliferation,and pluripotency.Additionally,IDH2 and GLUD1 KD induced abnormally high levels of trimethylation of lysine 20 of histone H4(H4K20me3)at the 4-cell stage,likely resulting in transcriptional repression of embryonic genome activation(EGA)-related genes.Notably,KD of lysine methyltransferase 5C(KMT5C)and supplementation with exogenousα-KG reduced H4K20me3 expression and partially rescued these defects,suggesting a critical role of IDH2 and GLUD1 in the epigenetic regulation and proper development of porcine embryos.Overall,this study highlights the significance of IDH2 and GLUD1 in maintaining normal embryonic development through their influence onα-KG production and subsequent epigenetic modifications.展开更多
G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem ce...G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem cells(mESCs)remain poorly understood.Here,we show that GPR160,a class A member of GPCRs,is dramatically downregulated concurrent with mESC differentiation into embryoid bodies in vitro.Knockdown of Gpr160 leads to downregulation of the expression of pluripotency-associated transcription factors and upregulation of the expression of lineage markers,accompanying with the ar-rest of the mESC cell-cycle in the G0/G1 phase.RNA-seq analysis shows that GPR160 participates in the JAK/STAT signaling pathway crucial formaintaining ESC stemness,and the knockdown of Gpr160 results in the downregulation of STAT3 phosphorylation level,which in turn is partially rescued by colivelin,a STAT3 activator.Consistent with these observations,GPR160 physically interacts with JAK1,and co-operates with leukemia inhibitory factor receptor(LIFR)and gp130 to activate the STAT3 pathway.In summary,our results suggest that GPR160 regulates mESC self-renewal and pluripotency by interacting with the JAK1-LIFR-gp130 complex to mediate the JAK1/STAT3 signaling pathway.展开更多
BACKGROUND Embryonic stem cells(ESCs)serve as a crucial ex vivo model,representing epiblast cells derived from the inner cell mass of blastocyst-stage embryos.ESCs exhibit a unique combination of self-renewal potency,...BACKGROUND Embryonic stem cells(ESCs)serve as a crucial ex vivo model,representing epiblast cells derived from the inner cell mass of blastocyst-stage embryos.ESCs exhibit a unique combination of self-renewal potency,unlimited proliferation,and pluripotency.The latter is evident by the ability of the isolated cells to differ-entiate spontaneously into multiple cell lineages,representing the three primary embryonic germ layers.Multiple regulatory networks guide ESCs,directing their self-renewal and lineage-specific differentiation.Apoptosis,or programmed cell death,emerges as a key event involved in sculpting and forming various organs and structures ensuring proper embryonic development.How-ever,the molecular mechanisms underlying the dynamic interplay between diffe-rentiation and apoptosis remain poorly understood.AIM To investigate the regulatory impact of apoptosis on the early differentiation of ESCs into cardiac cells,using mouse ESC(mESC)models-mESC-B-cell lym-phoma 2(BCL-2),mESC-PIM-2,and mESC-metallothionein-1(MET-1)-which overexpress the anti-apoptotic genes Bcl-2,Pim-2,and Met-1,respectively.METHODS mESC-T2(wild-type),mESC-BCL-2,mESC-PIM-2,and mESC-MET-1 have been used to assess the effect of potentiated apoptotic signals on cardiac differentiation.The hanging drop method was adopted to generate embryoid bodies(EBs)and induce terminal differentiation of mESCs.The size of the generated EBs was measured in each condition compared to the wild type.At the functional level,the percentage of cardiac differentiation was measured by calculating the number of beating cardiomyocytes in the manipulated mESCs compared to the control.At the molecular level,quantitative reverse transcription-polymerase chain reaction was used to assess the mRNA expression of three cardiac markers:Troponin T,GATA4,and NKX2.5.Additionally,troponin T protein expression was evaluated through immunofluorescence and western blot assays.RESULTS Our findings showed that the upregulation of Bcl-2,Pim-2,and Met-1 genes led to a reduction in the size of the EBs derived from the manipulated mESCs,in comparison with their wild-type counterpart.Additionally,a decrease in the count of beating cardiomyocytes among differentiated cells was observed.Furthermore,the mRNA expression of three cardiac markers-troponin T,GATA4,and NKX2.5-was diminished in mESCs overexpressing the three anti-apoptotic genes compared to the control cell line.Moreover,the overexpression of the anti-apoptotic genes resulted in a reduction in troponin T protein expression.CONCLUSION Our findings revealed that the upregulation of Bcl-2,Pim-2,and Met-1 genes altered cardiac differentiation,providing insight into the intricate interplay between apoptosis and ESC fate determination.展开更多
The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditi...The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on Leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectories of Leghorn embryos during early incubation at high altitudes.展开更多
Establishing intraspecific breeding and hybridization programs and determining genetic variability are two important issues for aquaculture. However, interspecific hybridization to improve growth and feeding efficienc...Establishing intraspecific breeding and hybridization programs and determining genetic variability are two important issues for aquaculture. However, interspecific hybridization to improve growth and feeding efficiency is limited. For this purpose, the embryonic and larval development of reciprocal crosses of Clarias gariepinus (Burchell, 1822) and Clarias jaensis (Boulenger, 1909) were studied under laboratory conditions. The fertilization rate varied from 63.33% to 92%, while the hatching rate ranged from 55.68% to 76% with the highest value in hybrids ♀Cg × ♂Cj. Crosses between ♀Cj × ♂Cj, ♀Cg × ♂Cj and ♀Cj × ♂Cg had embryonic stages similar to those of the pure sib ♀Cg x ♂Cg. All crosses, however, had different timing for the various embryological stages. Hatching occurred at 32 h 15 min and 38 h for ♀Cj × ♂Cj and ♀Cj × ♂Cg, and 23 h and 23 h 30 min, respectively, for ♀Cg × ♂Cg and ♀Cg × ♂Cj. However, both crosses produced viable larvae until the first external feeding. The external morphological features of the larvae were completely formed by the 10th day after hatching. The body forms of the crosses at this time were indistinguishable from the pure sib. This study thus laid the groundwork for further comparative studies on hybrid performance and characterization.展开更多
We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the...We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.展开更多
A key issue to be addressed in stem cell biology is the molecular signaling mechanism controlling embryonic stem （ES） cell pluripotency. Stem cell properties are dictated by specific transcription factors and epigen...A key issue to be addressed in stem cell biology is the molecular signaling mechanism controlling embryonic stem （ES） cell pluripotency. Stem cell properties are dictated by specific transcription factors and epigenetic processes such as DNA methylation and chromatin remodeling. Several cytokines/growth factors have been identified as critical ES cell regulators. However, there is a gap in our knowledge of the intracellular signaling pathways linking extracellular signals to transcriptional regulation in ES cells. This short review discusses the physiological role of Shp2, a cytoplasmic tyro- sine phosphatase, in the molecular switch governing ES cell self-renewal versus differentiation. Shp2 promotes ES cell differentiation, mainly through bi-directional modulation of Erk and Stat3 pathways. Deletion of Shp2 in mouse ES cells results in more efficient self-renewal. This observation provides the impetus to develop Shp2 inhibitors for maintenance and amplification of ES cells in culture.展开更多
Rhesus monkey embryonic stem（rES） cells have similar characteristics to human ES cells,and might be useful as a substitute model for preclinical research.Notch signaling is involved in the formation of bile ducts,wh...Rhesus monkey embryonic stem（rES） cells have similar characteristics to human ES cells,and might be useful as a substitute model for preclinical research.Notch signaling is involved in the formation of bile ducts,which are composed of cholangiocytes.However,little is known about the role of Notch signaling in cholangiocytic commitment of ES cells.We analyzed the effect of Notch signaling on the induction of cholangiocyte-like cells from rES cells.About 80% of definitive endoderm（DE） cells were generated from rES cells after treatment with activin A.After treatment with BMP4 and FGF1 on matrigel coated wells in serum-free medium,rES-derived DE gave rise to cholangiocyte-like cells by expression of cholangiocytic specific proteins（CK7,CK18,CK19,CK20,and OV-6） and genes（GSTPi,IB4,and HNF1β）.At the same time,expression of Notch 1 and Notch 2 mRNA were detected during cell differentiation,as well as their downstream target genes such as Hes 1 and Hes 5.Inhibition of the Notch signal pathway by L-685458 resulted in decreased expression of Notch and their downstream genes.In addition,the proportion of cholangiocyte-like cells declined from ～90% to ～20%.These results suggest that Notch signaling may play a critical role in cholangiocytic development from ES cells.展开更多
基金supported by the Scientific Research Projects Coordination Unit of Istanbul University(No.13930).
文摘Spermatozoa have a highly complex RNA profile.Several of these transcripts are suggested as biomarkers for male infertility and contribute to early development.To analyze the differences between sperm RNA quantity and expression of protamine(PRM1 and PRM2)and testis-specific histone 2B(TH2B)genes,spermatozoa from 33 patients who enrolled in assisted reproduction treatment(ART)program were analyzed.Sperm RNA of teratozoospermic(T),oligoteratozoospermic(OT),and normozoospermic(N)samples was extracted,and the differences in transcript levels among the study groups were analyzed by quantitative real-time polymerase chain reaction(qRT-PCR).The correlations of total RNA per spermatozoon and the expression of the transcripts were evaluated in relation to sperm characteristics and preimplantation embryo development.The mean(±standard deviation)RNA amount per spermatozoon was 28.48(±23.03)femtogram in the overall group and was significantly higher in the OT group than that in N and T groups.Total sperm RNA and gene expression of PRM1 and PRM2 genes were related to preimplantation embryo development and developmental arrest.Specific sperm characteristics were correlated with the expressions of PRM1,PRM2,or TH2B genes.We conclude that the sperm RNA amount and composition are important factors and might influence early embryonic development and also differ in different cases of male infertility.
基金German research Foundation(DFG,grant numbers:CH2321/1–1 and SCHO1231/7–1)JH has received a scholarship from the Chinese Scholarship Council(CSC No.:201908350115).
文摘The oviduct epithelium is the initial maternal contact site for embryos after fertilization,offering the microenviron-ment before implantation.This early gestation period is particularly sensitive to stress,which can cause reduced fertil-ity and reproductive disorders in mammals.Nevertheless,the local impact of elevated stress hormones on the ovi-duct epithelium has received limited attention to date,except for a few reports on polyovulatory species like mice and pigs.In this study,we focused on the effects of chronic maternal stress on cattle,given its association with infertil-ity issues in this monoovulatory species.Bovine oviduct epithelial cells(BOEC)differentiated at the air–liquid interface(ALI)were stimulated with 250 nmol/L cortisol for 1 or 3 weeks.Subsequently,they were assessed for morphology,bioelectrical properties,and gene expression related to oviduct function,glucocorticoid pathway,cortisol metabo-lism,inflammation,and apoptosis.Results revealed adverse effects of cortisol on epithelium structure,featured by deciliation,vacuole formation,and multilayering.Additionally,cortisol exposure led to an increase in transepithelial potential difference,downregulated mRNA expression of the major glucocorticoid receptor(NR3C1),upregulated the expression of cortisol-responsive genes(FKBP5,TSC22D3),and significant downregulation of oviductal glycopro-tein 1(OVGP1)and steroid receptors PGR and ESR1.The systematic comparison to a similar experiment previously performed by us in porcine oviduct epithelial cells,indicated that bovine cultures were more susceptible to elevated cortisol levels than porcine.The distinct responses between both species are likely linked to their divergence in the cortisol-induced expression changes of HSD11B2,an enzyme controlling the cellular capacity to metabolise cortisol.These findings provide insights into the species-specific reactions and reproductive consequences triggered by maternal stress.
文摘Following the publication of Xu et al.(2022),an error was identified in Figure 1D.Specifically,the top left panel was inadvertently duplicated during figure preparation.To ensure the accuracy and integrity of our published work,we request the publication of a corrigendum with the corrected image.We apologize for this oversight and any confusion it may have caused.The amended figure is provided in the updated Supplementary Materials.
基金supported by the Natural Science Foundation of Shandong Province(ZR2019MC059)the Traditional Chinese Medicine Science Project of Shandong Province(M-2023093)the Weifang Municipal Science and Technology Development Program(2025YX037).
文摘Human cytomegalovirus(HCMV)poses a significant risk of neural damage during pregnancy.As the most prevalent intrauterine infectious agent in low-and middle-income countries,HCMV disrupts the development of neural stem cells,leading to fetal malformations and abnormal structural and physiological functions in the fetal brain.This review summarizes the current understanding of how HCMV infection dysregulates the Wnt signaling pathway to induce fetal malformations and discusses current management strategies.
基金supported by the National Natural Science Foundation of China(Grant Nos.12090052,U24A2014,and 12325405).
文摘Spatial transcriptomics technology provides novel insights into the spatial organization of gene expression during embryonic development.In this study,we propose a method that integrates analysis across both temporal and spatial dimensions to investigate spatial transcriptomics data from mouse embryos at different developmental stages.We quantified the spatial expression pattern of each gene at various stages by calculating its Moran’s I.Furthermore,by employing time-series clustering to identify dynamic co-expression modules,we identified several developmentally stage-specific regulatory gene modules.A key finding was the presence of distinct,stage-specific gene network modules across different developmental periods:Early modules focused on morphogenesis,mid-stage on organ development,and late-stage on neural and tissue maturation.Functional enrichment analysis further confirmed the core biological functions of each module.The dynamic,spatially-resolved gene expression model constructed in this study not only provides new biological insights into the programmed spatiotemporal reorganization of gene regulatory networks during embryonic development but also presents an effective approach for analyzing complex spatiotemporal omics data.This work provides a new perspective for understanding developmental biology,regenerative medicine,and related fields.
基金supported by the Key R&D Program of Zhejiang(No.2023C03072)the Medical and Health Science and Technology Program of Zhejiang Province(No.2021PY007)and the National Key Research and Development Program of China(Nos.2021YFA1301100 and 2021YFA1301101).
文摘Periodontitis is a common oral disease caused by bacteria coupled with an excessive host immune response.Stem cell therapy can be a promising treatment strategy for periodontitis,but the relevant mechanism is complicated.This study aimed to explore the therapeutic potential of mitochondria from human embryonic stem cell-derived mesenchymal stem cells(hESC-MSCs)for the treatment of periodontitis.The gingival tissues of periodontitis patients are characterized by abnormal mitochondrial structure.Human gingival fibroblasts(HGFs)were exposed to 5μg/mL lipopolysaccharide(LPS)for 24 h to establish a cell injury model.When treated with hESC-MSCs or mitochondria derived from hESC-MSCs,HGFs showed reduced expression of inflammatory genes,increased adenosine triphosphate(ATP)level,decreased reactive oxygen species(ROS)production,and enhanced mitochondrial function compared to the control.The average efficiency of isolated mitochondrial transfer by hESC-MSCs was determined to be 8.93%.Besides,a therapy of local mitochondrial injection in mice with LPS-induced periodontitis showed a reduction in inflammatory gene expression,as well as an increase in both the mitochondrial number and the aspect ratio in gingival tissues.In conclusion,our results indicate that mitochondria derived from hESC-MSCs can reduce the inflammatory response and improve mitochondrial function in HGFs,suggesting that the transfer of mitochondria between hESC-MSCs and HGFs serves as a potential mechanism underlying the therapeutic effect of stem cells.
基金supported by the National Key Research and Development Program of China(2021YFA0805703,2019YFA0801800,and 2019YFA0802600)the National Natural Science Foundation of China(82330007,82122005,92268205 and 81970101)+1 种基金CAMS Innovation Fund for Medical Sciences(2021-I2M1-019)Haihe Laboratory of Cell Ecosystem Innovation Fund(22HHXBSS00027)。
文摘More and more studies have demonstrated that pseudogenes possess coding ability,and the functions of their transcripts in the development of diseases have been partially revealed.However,the role of pseudogenes in maintenance of normal physiological states and life activities has long been neglected.Here,we identify pseudogenes that are dynamically expressed during human early embryogenesis,showing different expression patterns from that of adult tissues.We explore the expression correlation between pseudogenes and the parent genes,partly due to their shared gene regulatory elements or the potential regulation network between them.The essential role of three pseudogenes,PI4KAP1,TMED10P1,and FBXW4P1,in maintaining self-renewal of human embryonic stem cells is demonstrated.We further find that the three pseudogenes might perform their regulatory functions by binding to proteins or microRNAs.The pseudogene-related single-nucleotide polymorphisms are significantly associated with human congenital disease,further illustrating their importance during early embryonic development.Overall,this study is an excavation and exploration of functional pseudogenes during early human embryonic development,suggesting that pseudogenes are not only capable of being specifically activated in pathological states,but also play crucial roles in the maintenance of normal physiological states.
基金supported by the Ministry of Science and Technology of the People’s Republic of China (No.2020YFA0907500)the National Natural Science Foundation of China (Nos.22150710514,22021003,and 22106174)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDPB200202)the Postdoc Science Foundation of China (No.2021M693322)。
文摘In recent years,neonicotinoids(NEOs)and organophosphate esters(OPEs)have been widely used as substitutes for traditional pesticides and brominated fame-retardants,respectively.Previous studies have shown that those compounds can be frequently detected in environmental and human samples,are able to penetrate the placental barrier,and are toxic to animals.Thus,it is reasonable to speculate that NEOs and OPEs may have potential adverse effects in humans,especially during development.We employed a human embryonic stem cell differentiation-and liver S9 fraction metabolism-based fast screening model to assess the potential embryonic toxicity of those two types of chemicals.We show that four NEO and five OPE prototypes targeted mostly ectoderm specification,as neural ectoderm and neural crest genes were down-regulated,and surface ectoderm and placode markers up-regulated.Human liver S9 fraction's treatment could generally reduce the effects of the chemicals,except in a few specific instances,indicating the liver may detoxify NEOs and OPEs.Our findings suggest that NEOs and OPEs interfere with human early embryonic development.
基金Supported by the Shandong Provincial Traditional Chinese Medicine Science and Technology Development Program,No.C-262the 2021 Science and Technology Innovation Research Project of Shandong Maternal and Child Health Association,No.2021-19-24.
文摘BACKGROUND This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure.CASE SUMMARY Here,we collected and described the clinical data of a patient with early embryonic development stagnation after repeated in vitro fertilization attempts for primary infertility at the Department Reproductive Center of Zaozhuang Maternal and Child Healthcare Hospital.We also detected the whole-exon gene of the patient's spouse and parents,and conducted bioinformatics analysis to determine the pathogenesis of the gene.CONCLUSION A novel mutant of the TUBB8 gene[c.602G>T(p.C201F)]was identified,and this mutant provided new data on the genotype-phenotype relationships of related diseases.
基金supported by the National Key Research and Development Program of China(2021YFF1000303)the National Nature Science Foundation of China(32072073,32001500,and 32101777)the Sichuan Science and Technology Program,China(2021JDTD0004 and 2021YJ0476)。
文摘Genetic transformation has been an effective technology for improving the agronomic traits of maize.However,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype dependence.In this study,we performed genomic sequencing for 80 core maize germplasms and constructed a high-density genomic variation map using our newly developed pipeline(MQ2Gpipe).Based on the induction rate of EC(REC),these inbred lines were categorized into three subpopulations.The low-REC germplasms displayed more abundant genetic diversity than the high-REC germplasms.By integrating a genome-wide selective signature screen and region-based association analysis,we revealed 95.23 Mb of selective regions and 43 REC-associated variants.These variants had phenotypic variance explained values ranging between 21.46 and 49.46%.In total,103 candidate genes were identified within the linkage disequilibrium regions of these REC-associated loci.These genes mainly participate in regulation of the cell cycle,regulation of cytokinesis,and other functions,among which MYB15 and EMB2745 were located within the previously reported QTL for EC induction.Numerous leaf area-associated variants with large effects were closely linked to several REC-related loci,implying a potential synergistic selection of REC and leaf size during modern maize breeding.
基金supported by the National Key R&D Program of China (Nos.2022YFC3400700,2022YFA0806600)the National Natural Science Foundation of China (No.22074110)+3 种基金Guangdong Basic and Applied Basic Research Foundation (No.2022A1515110550)Central Public-interest Scientific Institution Basal Research Fund,South China Sea Fisheries Research Institute,CAFS (No.2021TS02)Guangzhou Basic and Applied Basic Research Foundation (No.2023A04J1337)Central Public-interest Scientific Institution Basal Research Fund,CAFS (No.2023TD78)。
文摘Regulation of cell fate requires the establishment and erasure of 5-methylcytosine(5mC) in genomic DNA.The formation of 5mC is achieved by DNA cytosine methyltransferases(DNMTs),whereas the removal of5mC can be accomplished by various pathways.Aside from ten-eleven translocation(TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase(TDG)-initiated base excision repair(BER),the direct deformylation of 5-formylcytosine(5fC) and decarboxylation of 5-carboxylcytosine(5caC) have also been discovered as the novel DNA demethylation pathways.Although these novel demethylation pathways have been identified in stem cells and somatic cells,their precise roles in regulating cell fate remain unclear.Here,we differentiate mouse embryonic stem cells(mESCs) into mouse embryoid bodies(mEBs),followed by further differentiation into mouse neural stem cells(mNSCs) and finally into mouse neurons(mNeurons).During this sequential differentiation process,we employ probe molecules,namely2'-fluorinated 5-formylcytidine(F-5fC) and 2'-fluorinated 5-carboxyldeoxycytidine(F-5caC),for metabolic labeling.The results of mass spectrometry(MS) analysis demonstrate the deformylation and decarboxylation activities are progressively decreased and increased respectively during differentiation process,and this opposite demethylation tendency is not associated with DNMTs and TETs.
基金National Key R&D Program of China (No.2018YFA0901101)the National Natural Science Foundation of China (Nos.22193050,92043301,22176203 and 22276212)the Sanming Project of Medicine in Shenzhen (No.SZSM201811070)。
文摘Investigating the development toxicity of perfuorinated iodine alkanes(PFIs)is critical,given their estrogenic effects through binding with estrogen receptors(ERs).In the present study,two PFIs,including dodecafuoro-1,6-diiodohexane(PFHx DI)and tridecafuorohexyl iodide(PFHx I),with binding preference to ERαand ERβ,respectively,were selected to evaluate their effects on proliferation and differentiation of the mouse embryonic stem cells(m ESCs).The results revealed that,similar to E_(2),50μmol/L PFHx DI accelerated the cell proliferation of the m ESCs.The PFI stimulation at the exposure concentrations of 2–50μmol/L promoted the differentiation of the m ESCs as characterized by the upregulation of differentiation-related biomarkers(i.e.,Otx2 and Dnmt3β)and downregulation of pluripotency genes(i.e.,Oct4,Nanog,Sox2,Prdm14 and Rex1).Comparatively,PFHx DI exhibited higher induction effect on the differentiation of the m ESCs than did PFHx I.The tests on ER signaling indicated that both PFI compounds induced exposure concentration-dependent expressions of ER signaling-related biomarkers(i.e.,ERα,ERβand Caveolin-1)in the m ESCs,and the downstream ER responsive genes(i.e.,c-fos,c-myc and c-jun)well responded to PFHx I stimulation.The role of ER in PFI-induced effects on the m ESCs was further validated by the antagonistic experiments using an ER inhibitor(ICI).The findings demonstrated that PFIs triggered ER signaling,and perturbed the differentiation program of the m ESCs,causing the potential health risk during early stage of development.
基金supported by the National Research Foundation(NRF)of Korea grant funded by the Korean government(MSIT)(2022R1A2C300769),Republic of Korea。
文摘Isocitrate dehydrogenase 2(IDH2)and glutamate dehydrogenase 1(GLUD1)are key enzymes involved in the production ofα-ketoglutarate(α-KG),a metabolite central to the tricarboxylic acid cycle and glutamine metabolism.In this study,we investigated the impact of IDH2 and GLUD1 on early porcine embryonic development following IDH2 and GLUD1 knockdown(KD)via doublestranded RNA(dsRNA)microinjection.Results showed that KD reducedα-KG levels,leading to delayed embryonic development,decreased blastocyst formation,increased apoptosis,reduced blastomere proliferation,and pluripotency.Additionally,IDH2 and GLUD1 KD induced abnormally high levels of trimethylation of lysine 20 of histone H4(H4K20me3)at the 4-cell stage,likely resulting in transcriptional repression of embryonic genome activation(EGA)-related genes.Notably,KD of lysine methyltransferase 5C(KMT5C)and supplementation with exogenousα-KG reduced H4K20me3 expression and partially rescued these defects,suggesting a critical role of IDH2 and GLUD1 in the epigenetic regulation and proper development of porcine embryos.Overall,this study highlights the significance of IDH2 and GLUD1 in maintaining normal embryonic development through their influence onα-KG production and subsequent epigenetic modifications.
基金This work was funded by grants from the National Key Research and Development Program of China(2019YFA0801402)the National Natural Science Foundation of China(82271890)+3 种基金the Shanghai Key Clinical Specialty Project(shslczdzk05705)the Shanghai Top Priority Key Discipline Project(2017zz02019)Innovative Research Team of High-Level Local Universities in Shanghai(SHSMU-ZDCX20212200)the Macao Science and Technology Development fund(FDCT)(0092/2022/A2 and 003/2022/ALC).
文摘G-protein-coupled receptors(GPCRs)are the largest family of transmembrane receptors and regulate various physiological and pathological processes.Despite extensive studies,the roles of GPCRs in mouse embryonic stem cells(mESCs)remain poorly understood.Here,we show that GPR160,a class A member of GPCRs,is dramatically downregulated concurrent with mESC differentiation into embryoid bodies in vitro.Knockdown of Gpr160 leads to downregulation of the expression of pluripotency-associated transcription factors and upregulation of the expression of lineage markers,accompanying with the ar-rest of the mESC cell-cycle in the G0/G1 phase.RNA-seq analysis shows that GPR160 participates in the JAK/STAT signaling pathway crucial formaintaining ESC stemness,and the knockdown of Gpr160 results in the downregulation of STAT3 phosphorylation level,which in turn is partially rescued by colivelin,a STAT3 activator.Consistent with these observations,GPR160 physically interacts with JAK1,and co-operates with leukemia inhibitory factor receptor(LIFR)and gp130 to activate the STAT3 pathway.In summary,our results suggest that GPR160 regulates mESC self-renewal and pluripotency by interacting with the JAK1-LIFR-gp130 complex to mediate the JAK1/STAT3 signaling pathway.
基金Supported by the National Council for Scientific Research in Lebanon,CNRS-L.
文摘BACKGROUND Embryonic stem cells(ESCs)serve as a crucial ex vivo model,representing epiblast cells derived from the inner cell mass of blastocyst-stage embryos.ESCs exhibit a unique combination of self-renewal potency,unlimited proliferation,and pluripotency.The latter is evident by the ability of the isolated cells to differ-entiate spontaneously into multiple cell lineages,representing the three primary embryonic germ layers.Multiple regulatory networks guide ESCs,directing their self-renewal and lineage-specific differentiation.Apoptosis,or programmed cell death,emerges as a key event involved in sculpting and forming various organs and structures ensuring proper embryonic development.How-ever,the molecular mechanisms underlying the dynamic interplay between diffe-rentiation and apoptosis remain poorly understood.AIM To investigate the regulatory impact of apoptosis on the early differentiation of ESCs into cardiac cells,using mouse ESC(mESC)models-mESC-B-cell lym-phoma 2(BCL-2),mESC-PIM-2,and mESC-metallothionein-1(MET-1)-which overexpress the anti-apoptotic genes Bcl-2,Pim-2,and Met-1,respectively.METHODS mESC-T2(wild-type),mESC-BCL-2,mESC-PIM-2,and mESC-MET-1 have been used to assess the effect of potentiated apoptotic signals on cardiac differentiation.The hanging drop method was adopted to generate embryoid bodies(EBs)and induce terminal differentiation of mESCs.The size of the generated EBs was measured in each condition compared to the wild type.At the functional level,the percentage of cardiac differentiation was measured by calculating the number of beating cardiomyocytes in the manipulated mESCs compared to the control.At the molecular level,quantitative reverse transcription-polymerase chain reaction was used to assess the mRNA expression of three cardiac markers:Troponin T,GATA4,and NKX2.5.Additionally,troponin T protein expression was evaluated through immunofluorescence and western blot assays.RESULTS Our findings showed that the upregulation of Bcl-2,Pim-2,and Met-1 genes led to a reduction in the size of the EBs derived from the manipulated mESCs,in comparison with their wild-type counterpart.Additionally,a decrease in the count of beating cardiomyocytes among differentiated cells was observed.Furthermore,the mRNA expression of three cardiac markers-troponin T,GATA4,and NKX2.5-was diminished in mESCs overexpressing the three anti-apoptotic genes compared to the control cell line.Moreover,the overexpression of the anti-apoptotic genes resulted in a reduction in troponin T protein expression.CONCLUSION Our findings revealed that the upregulation of Bcl-2,Pim-2,and Met-1 genes altered cardiac differentiation,providing insight into the intricate interplay between apoptosis and ESC fate determination.
文摘The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on Leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectories of Leghorn embryos during early incubation at high altitudes.
文摘Establishing intraspecific breeding and hybridization programs and determining genetic variability are two important issues for aquaculture. However, interspecific hybridization to improve growth and feeding efficiency is limited. For this purpose, the embryonic and larval development of reciprocal crosses of Clarias gariepinus (Burchell, 1822) and Clarias jaensis (Boulenger, 1909) were studied under laboratory conditions. The fertilization rate varied from 63.33% to 92%, while the hatching rate ranged from 55.68% to 76% with the highest value in hybrids ♀Cg × ♂Cj. Crosses between ♀Cj × ♂Cj, ♀Cg × ♂Cj and ♀Cj × ♂Cg had embryonic stages similar to those of the pure sib ♀Cg x ♂Cg. All crosses, however, had different timing for the various embryological stages. Hatching occurred at 32 h 15 min and 38 h for ♀Cj × ♂Cj and ♀Cj × ♂Cg, and 23 h and 23 h 30 min, respectively, for ♀Cg × ♂Cg and ♀Cg × ♂Cj. However, both crosses produced viable larvae until the first external feeding. The external morphological features of the larvae were completely formed by the 10th day after hatching. The body forms of the crosses at this time were indistinguishable from the pure sib. This study thus laid the groundwork for further comparative studies on hybrid performance and characterization.
基金supported by the National Natural Science Fundation of China(30730029)
文摘We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.
文摘A key issue to be addressed in stem cell biology is the molecular signaling mechanism controlling embryonic stem （ES） cell pluripotency. Stem cell properties are dictated by specific transcription factors and epigenetic processes such as DNA methylation and chromatin remodeling. Several cytokines/growth factors have been identified as critical ES cell regulators. However, there is a gap in our knowledge of the intracellular signaling pathways linking extracellular signals to transcriptional regulation in ES cells. This short review discusses the physiological role of Shp2, a cytoplasmic tyro- sine phosphatase, in the molecular switch governing ES cell self-renewal versus differentiation. Shp2 promotes ES cell differentiation, mainly through bi-directional modulation of Erk and Stat3 pathways. Deletion of Shp2 in mouse ES cells results in more efficient self-renewal. This observation provides the impetus to develop Shp2 inhibitors for maintenance and amplification of ES cells in culture.
基金supported by research grants from Zhejiang Natural Sciences Foundation of China (Y2110911 Y2080996)the National Key Technologies R&D Program of China (2007CB947701)
文摘Rhesus monkey embryonic stem（rES） cells have similar characteristics to human ES cells,and might be useful as a substitute model for preclinical research.Notch signaling is involved in the formation of bile ducts,which are composed of cholangiocytes.However,little is known about the role of Notch signaling in cholangiocytic commitment of ES cells.We analyzed the effect of Notch signaling on the induction of cholangiocyte-like cells from rES cells.About 80% of definitive endoderm（DE） cells were generated from rES cells after treatment with activin A.After treatment with BMP4 and FGF1 on matrigel coated wells in serum-free medium,rES-derived DE gave rise to cholangiocyte-like cells by expression of cholangiocytic specific proteins（CK7,CK18,CK19,CK20,and OV-6） and genes（GSTPi,IB4,and HNF1β）.At the same time,expression of Notch 1 and Notch 2 mRNA were detected during cell differentiation,as well as their downstream target genes such as Hes 1 and Hes 5.Inhibition of the Notch signal pathway by L-685458 resulted in decreased expression of Notch and their downstream genes.In addition,the proportion of cholangiocyte-like cells declined from ～90% to ～20%.These results suggest that Notch signaling may play a critical role in cholangiocytic development from ES cells.
