The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(B...The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(Becn1),a major regulator of mammalian autophagy,exclusively in the megakaryocytic lineage disrupted autophagy in platelets but did not compromise megakaryopoiesis or the formation and function of platelets.Unexpectedly,conditional Becn1 deletion in male mice led to a remarkable increase in bone mass with improved bone quality,in association with a decrease in sex hormone binding globulin(SHBG)and an increase in free testosterone(FT).In vivo Becn1 overexpression in megakaryocytic lineage-specific cells reduced bone mass and quality,along with an increase in SHBG and a decrease in FT.Transplantation of wild-type bone marrow cells into megakaryocytic lineage Becn1-deficient male mice restored bone mass and normalized SHBG and FT.Furthermore,bilateral orchiectomy of Becn1^(f/f);Pf4-iCre mice,which are crippled with the production of testosterone,resulted in a reduction in bone mass and quality,whereas in vivo overexpression of SHBG,specifically in the liver of Becn1^(f/f);Pf4-iCre mice,decreased FT and reduced bone mass and quality.In addition,metformin treatment,which induces SHBG expression,reduced FT and normalized bone mass in Becn1^(f/f);Pf4-iCre mice.We thus concluded that Becn1 of the megakaryocytic lineage is dispensable locally for platelet hemostasis but limits bone mass by increasing SHBG,which in turn reduces the FT of male mice.Our findings highlight a mechanism by which Becn1 from megakaryocytic lineage cells distally balances bone growth.展开更多
The reconstruction of demographic history using ancient and modern genomic resources reveals extensive interactions and admixture between ancient nomadic pastoralists and the social organizations of the Chinese Centra...The reconstruction of demographic history using ancient and modern genomic resources reveals extensive interactions and admixture between ancient nomadic pastoralists and the social organizations of the Chinese Central Plain.However,the extent to which Y-chromosome genetic legacies from nomadic emperor-related ancestral lineages influence the Chinese paternal gene pool remains unclear.Here,we genotype 2717 ethnolinguistically diverse samples belonging to C2a lineages,perform whole-genome sequencing on 997 representative samples,and integrate these data with ancient genomic sequences.We reconstruct the evolutionary histories of Northern Zhou-,Qing emperor-,and pastoralist-related lineages to assess their genetic impact on modern Chinese populations.This reassembled fine-scale Ychromosome phylogeny identifies deep divergence and five Neolithic expansion events contributing differently to the formation of northern Chinese populations.Phylogeographic modeling indicates that the nomadic empires of the Northern Zhou and Qing dynasties genetically originated from the Mongolian Plateau.Phylogenetic topology and shared haplotype patterns show that three upstream ancestors of Northern Zhou(C2a1a1b1a2a1b-FGC28857),Donghu tribe(C2a1a1b1-F1756),and Qing(C2a1a3a2-F10283)emperor-related lineages expanded during the middle Neolithic,contributing significantly to genetic flow between ancient northeastern Asians and modern East Asians.Notably,this study reveals limited direct contributions of Emperor Wu of Northern Zhou’s lineages to modern East Asians.展开更多
Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,mar...Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,marrow adipogenic lineage precursors(MALPs),and showed that its production of RANKL stimulates bone resorption in young mice using Adipoq-Cre.To exclude developmental defects and to investigate the role of MALPs-derived RANKL in adult bone,we generated inducible reporter mice(Adipoq-CreER Tomato)and RANKL deficient mice(Adipoq-CreER RANKLflox/flox,iCKO).Single cell-RNA sequencing data analysis and lineage tracing revealed that Adipoq+cells contain not only MALPs but also some mesenchymal progenitors capable of osteogenic differentiation.In situ hybridization showed that RANKL mRNA is only detected in MALPs,but not in osteogenic cells.RANKL deficiency in MALPs induced at 3 months of age rapidly increased trabecular bone mass in long bones as well as vertebrae due to diminished bone resorption but had no effect on the cortical bone.Ovariectomy(OVX)induced trabecular bone loss at both sites.RANKL depletion either before OVX or at 6 weeks post OVX protected and restored trabecular bone mass.Furthermore,bone healing after drill-hole injury was delayed in iCKO mice.Together,our findings demonstrate that MALPs play a dominant role in controlling trabecular bone resorption and that RANKL from MALPs is essential for trabecular bone turnover in adult bone homeostasis,postmenopausal bone loss,and injury repair.展开更多
BACKGROUND Mixed lineage kinase domain-like protein(MLKL)serves as a critical mediator in necroptosis,a form of regulated cell death linked to various liver diseases.This study aims to specifically investigate the rol...BACKGROUND Mixed lineage kinase domain-like protein(MLKL)serves as a critical mediator in necroptosis,a form of regulated cell death linked to various liver diseases.This study aims to specifically investigate the role of MLKL’s adenosine triphosphate(ATP)-binding pocket in facilitating necroptosis-independent pathways that may contribute to liver disease progression.By focusing on this mechanism,we seek to identify potential therapeutic targets that can modulate MLKL activity,offering new strategies for the prevention and treatment of liver-related pathologies.AIM To investigate the possibility of using the ATP-binding pocket-associated,necro-ptosis-independent MLKL pathway as a target for liver diseases.METHODS Cell death following necroptosis stimuli was evaluated using cell proliferation assays,flow cytometry,and electron microscopy in various cells.The human liver organoid system was used to evaluate whether the MLKL ATP pocket-binding inhibitor could attenuate inflammation.Additionally,alcoholic and non-alcoholic fatty liver diseases animal models were used to determine whether MLKL ATP pocket inhibitors could attenuate liver injury.RESULTS While an MLKL ATP pocket-binding inhibitor did not prevent necroptosis-induced cell death in RAW 264.7 cells,it did reduce the necroptosis-led expression of CXCL2,ICAM,and VCAM.Notably,MLKL ATP pocket inhibitor diminishes the expression of CXCL2,ICAM,and VCAM by inhibiting the IκB kinase and nuclear factor kappa-B pathways without inducing necroptosis-induced cell death in two-dimensional cell culture as well as the human-derived liver organoid system.Although MLKL ATP-binding inhibitor was ineffective in non-alcoholic fatty liver disease animal models,MLKL ATP-binding inhibitor attenuated hepatic inflammation in the alcoholic liver disease model.CONCLUSION MLKL ATP pocket-binding inhibitor exerted anti-inflammatory effects through the necroptosis-independent MLKL pathway in an animal model of alcoholic liver disease.展开更多
Based on the study of two Early Pleistocene human skulls found in Yunxian County,Hubei Province,China,Ji et al.(2024)suggested that Homo orientalis was the common ancestor of the sapiens lineage and the longi lineage,...Based on the study of two Early Pleistocene human skulls found in Yunxian County,Hubei Province,China,Ji et al.(2024)suggested that Homo orientalis was the common ancestor of the sapiens lineage and the longi lineage,and proposed that both the two lineages originated from East Asia.We further proposed that Genus Homo should be divided into two subgenera:Subgenus Homo and Subgenus Parahomo.All members of the sapiens lineage would be assigned to Subgenus Homo,and all members of the longi lineage would be grouped into Subgenus Parahomo.Homo(Parahomo)heidelbergensis and Homo(Parahomo)neanderthalensis also were the members of the longi lineage,an evolutionary branch spreaded from East Asia to Africa and Europe more than 600,000 years ago.This paper mainly makes an introduction to the speciation,classification and phylogeny of the longi lineage.The longi lineage and the sapiens lineage are″sister group″relationship,but the longi lineage is an extinct lineage,having nothing to do with our modern people.展开更多
In this letter,we comment on the article by Xuan Yuan et al,published in the recent issue of the World Journal of Gastroenterology.Mixed lineage kinase domainlike protein(MLKL)exhibits cell-type-specific functions in ...In this letter,we comment on the article by Xuan Yuan et al,published in the recent issue of the World Journal of Gastroenterology.Mixed lineage kinase domainlike protein(MLKL)exhibits cell-type-specific functions in liver parenchymal and non-parenchymal cells,playing dual roles in the pathogenesis of liver diseases.In hepatocytes,MLKL primarily mediates necroptosis and inhibits autophagy,thereby exacerbating liver injury.Conversely,in non-parenchymal liver cells,MLKL modulates inflammatory responses and promotes fibrotic processes,thereby driving disease progression.Notably,MLKL also demonstrates protective functions under specific conditions.For instance,MLKL can inhibit intracellular bacterial replication,promote endosomal trafficking,and facilitate the generation and release of extracellular vesicles,potentially exerting hepatoprotective effects.Understanding these cell-type-specific mechanisms of MLKL action,including its dual roles in promoting injury and providing protection,is crucial for elucidating the complex pathogenesis of liver diseases and developing targeted therapeutic strategies.展开更多
Although mixed lineage kinase domain-like protein(MLKL)is widely recognized as a critical effector in the necroptotic signaling pathway,MLKL plays broader regulatory roles beyond programmed necroptosis.Notably,Xuan Yu...Although mixed lineage kinase domain-like protein(MLKL)is widely recognized as a critical effector in the necroptotic signaling pathway,MLKL plays broader regulatory roles beyond programmed necroptosis.Notably,Xuan Yuan et al demonstrated that CPD4,an ATP-binding pocket inhibitor of MLKL,significantly reduces liver inflammation and improves liver function by inhibiting NF-κB signaling,suggesting its use as a potential therapeutic candidate for alcoholic liver disease.However,the pharmacokinetic properties and long-term toxicity of CPD4 require further evaluation.Moreover,a single therapeutic strategy targeting MLKL may not be sufficient.Future studies should focus on the precise regulation of MLKL and develop combination therapies to achieve dual intervention of inflammatory and cell death pathways.This paper provides an important theoretical foundation for translational research on MLKL-targeted therapy.However,its clinical translation requires overcoming existing limitations and further elucidating the regulatory network of MLKL in complex microenvironments.展开更多
Objective:Ulcerative colitis is closely associated with intestinal stem cell(ISC)loss and impaired intestinal mucus barrier.Sinisan(SNS),a compound Chinese herbal medicine,has a long history in the treatment of intest...Objective:Ulcerative colitis is closely associated with intestinal stem cell(ISC)loss and impaired intestinal mucus barrier.Sinisan(SNS),a compound Chinese herbal medicine,has a long history in the treatment of intestinal dysfunction,yet whether SNS can relieve acute experimental colitis by modulating ISC proliferation and secretory cell differentiation has not been studied.Our study tested the effect of SNS against acute colitis and focused on the mechanisms involving intestinal barrier recovery.Methods:Network pharmacology analysis and blood entry component analysis of SNS were used to explore the underlying mechanism by which SNS affects the acute dextran sulfate sodium(DSS)-induced murine colitis model.RNA-sequencing was used to demonstrate the mechanism.Further,reverse transcription-quantitative polymerase chain reaction,immunofluorescence staining,and alcian blue and periodic acid-Schiff staining were performed in vivo and in the colonic organoids to investigate the cell lineage differentiation-related mechanism of SNS.Furthermore,potential active ingredients from SNS were predicted by network pharmacology analysis.Results:SNS dramatically suppressed DSS-induced acute colonic inflammation in mice.RNA-sequencing analysis revealed downregulation of inflammation and apoptosis-related genes,and upregulation of lipid metabolism and proliferation-related genes,such as Irf7,Ppara,Clspn and Hspa5.Additionally,ISC renewal and intestinal secretory cell lineage commitment were significantly promoted by SNS both in vivo and in vitro in colonic organoids,leading to enhanced mucin expression.Furthermore,potential active ingredients from SNS that mediated inflammation,lipid metabolism,proliferation,apoptosis,stem cells and secretory cells were predicted using a network pharmacology approach.Conclusion:Our study shed light on the underlying mechanism of SNS in attenuating acute colitis from the perspective of ISC renewal and secretory lineage cell differentiation,suggesting a of novel therapeutic strategy against colitis.展开更多
Cell lineage tracing is a key technology for describing the developmental history of individual progenitor cells and assembling them to form a lineage development tree.However,traditional methods have limitations of p...Cell lineage tracing is a key technology for describing the developmental history of individual progenitor cells and assembling them to form a lineage development tree.However,traditional methods have limitations of poor stability and insufficient reso-lution.As an efficient and flexible gene editing tool,CRISPR-Cas9 system has been widely used in biological research.Furthermore,CRISPR-Cas9 gene editing-based tracing methods can introduce fluorescent proteins,reporter genes,or DNA barcodes for high-throughput sequencing,enabling precise lineage analysis,significantly im-proving precision and resolution,and expanding its application range.In this review,we summarize applications of CRISPR-Cas9 system in cell lineage tracing,with special emphasis on its successful applications in traditional model animals(e.g.,zebrafish and mice),large animal models(pigs),and human cells or organoids.We also discussed its potential prospects and challenges in xenotransplantation and regenerative medicine.展开更多
Unraveling the lineage relationships of all descendants from a zygote is fundamental to advancing our understanding of developmental and stem cell biology.However,existing cell barcoding technologies in zebrafish lack...Unraveling the lineage relationships of all descendants from a zygote is fundamental to advancing our understanding of developmental and stem cell biology.However,existing cell barcoding technologies in zebrafish lack the resolution to capture the majority of cell divisions during embryogenesis.A recently developed method,a substitution mutation-aided lineage-tracing system(SMALT),successfully reconstructed high-resolution cell phylogenetic trees for Drosophila melanogaster.Here,we implement the SMALT system in zebrafish,recording a median of 14 substitution mutations on a one-kilobase-pair barcoding sequence for one-day post-fertilization embryos.Leveraging this system,we reconstruct four cell lineage trees for zebrafish fin cells,encompassing both original and regenerated fin.Each tree consists of hundreds of internal nodes with a median bootstrap support of 99%.Analysis of the obtained cell lineage trees reveals that regenerated fin cells mainly originate from cells in the same part of the fins.Through multiple times sampling germ cells from the same individual,we show the stability of the germ cell pool and the early separation of germ cell and somatic cell progenitors.Our system offers the potential for reconstructing high-quality cell phylogenies across diverse tissues,providing valuable insights into development and disease in zebrafish.展开更多
Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At pre...Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.展开更多
Genetic lineage tracing has been widely employed to investigate cell lineages and fate.However,conventional reporting systems often label the entire cytoplasm,making it challenging to discern cell boundaries.Additiona...Genetic lineage tracing has been widely employed to investigate cell lineages and fate.However,conventional reporting systems often label the entire cytoplasm,making it challenging to discern cell boundaries.Additionally,single Cre-lox P recombination systems have limitations in tracing specific cell populations.This study proposes three reporting systems utilizing Cre,Dre,and Dre+Cre mediated recombination.These systems incorporate td Tomato expression on the cell membrane and Phi YFP expression within the nucleus,allowing for clear observation of the nucleus and membrane.The efficacy of these systems is successfully demonstrated by labeling cardiomyocytes and hepatocytes.The potential for dynamic visualization of the cell membrane is showcased using intravital imaging microscopy or threedimensional imaging.Furthermore,by combining this dual recombinase system with the Pro Tracer system,hepatocyte proliferation is traced with enhanced precision.This reporting system holds significant importance for advancing the understanding of cell fate studies in development,homeostasis,and diseases.展开更多
The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylo...The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylogeny-based trait evolution.However,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear discordant.Here,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium subg.Cyathophora.Both concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS distribution.However,GTD was high across the genomes of subg.Cyathophora:~27%e38.9%of the SCG trees were in conflict with the species tree.Plasmid and nuclear incongruence was also present.Our coalescent simulations indicated that such GTD was mainly a product of ILS.Our hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the subg.Cyathophora phylogeny may have caused the character transition,as well as the anomalous cpDNA tree.Our study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.展开更多
In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in...In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in developmental biology and other related fields.Recent technological advancements,especially those in editable genomic barcodes and single-cell high-throughput sequencing,have sparked a new wave of experimental methods for reconstructing CLTs.Here we review the existing experimental approaches to the reconstruction of CLT,which are broadly categorized as either image-based or DNA barcode-based methods.In addition,we present a summary of the related literature based on the biological insight pro-vided by the obtained CLTs.Moreover,we discuss the challenges that will arise as more and better CLT data become available in the near future.Genomic barcoding-based CLT reconstructions and analyses,due to their wide applicability and high scalability,offer the potential for novel biological discoveries,especially those related to general and systemic properties of the developmental process.展开更多
The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variati...The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variation.In this study,69 mitogenomes of the Black-throated Tit(Aegithalos concinnus)were assembled and annotated from a large number of short reads generated using high-throughput sequencing technology.Comparative analyses revealed that mitogenomic characteristics such as length,gene and nucleotide composition,codon usage,and duplicated control regions were relatively conserved despite substantial intraspecies morphological changes.Yet,all the individuals from the subspecies A.c.iredalei had one more nucleotide in the 12S rRNA than the other studied subspecies.Phylogenetic analyses showed five distinct lineages based on the complete mitogenomes and the 13 combined protein-coding genes,whereas only four lineages were observed when using the duplicate control regions.Most interestingly,each lineage had both copies of the control regions of the comprising individuals,indicating that the paralogous control regions were more similar than the orthologous sequences from the distinct lineages.This suggested the control regions had undergone concerted evolution.The Black-throated Tit has complex evolutionary history and needs further investigating the taxonomic status of these lineages,as well as the underlying evolutionary processes.Our findings call for more research on intraspecies mitogenomic variation.展开更多
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the pathogen responsible for coronavirus disease 2019(COVID-19),continues to evolve,giving rise to more variants and global reinfections.Previous research ha...Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the pathogen responsible for coronavirus disease 2019(COVID-19),continues to evolve,giving rise to more variants and global reinfections.Previous research has demonstrated that barcode segments can effectively and cost-efficiently identify specific species within closely related populations.In this study,we designed and tested RNA barcode segments based on genetic evolutionary relationships to facilitate the efficient and accurate identification of SARS-CoV-2 from extensive virus samples,including human coronaviruses(HCoVs)and SARSr-CoV-2 lineages.Nucleotide sequences sourced from NCBI and GISAID were meticulously selected and curated to construct training sets,encompassing 1733 complete genome sequences of HCoVs and SARSr-CoV-2 lineages.Through genetic-level species testing,we validated the accuracy and reliability of the barcode segments for identifying SARS-CoV-2.Subsequently,75 main and subordinate species-specific barcode segments for SARS-CoV-2,located in ORF1ab,S,E,ORF7a,and N coding sequences,were intercepted and screened based on single-nucleotide polymorphism sites and weighted scores.Post-testing,these segments exhibited high recall rates(nearly 100%),specificity(almost 30%at the nucleotide level),and precision(100%)performance on identification.They were eventually visualized using one and two-dimensional combined barcodes and deposited in an online database(http://virusbarcodedatabase.top/).The successful integration of barcoding technology in SARS-CoV-2 identification provides valuable insights for future studies involving complete genome sequence polymorphism analysis.Moreover,this cost-effective and efficient identification approach also provides valuable reference for future research endeavors related to virus surveillance.展开更多
Regenerating functional new neurons in the adult mammalian central nervous system has been proven to be very challenging due to the inability of neurons to divide and repopulate themselves after neuronal loss.Glial ce...Regenerating functional new neurons in the adult mammalian central nervous system has been proven to be very challenging due to the inability of neurons to divide and repopulate themselves after neuronal loss.Glial cells,on the other hand,can divide and repopulate themselves under injury or diseased conditions.We have previously reported that ectopic expression of NeuroD1 in dividing glial cells can directly convert them into neurons.Here,using astrocytic lineage-tracing reporter mice(Aldh1l1-CreERT2 mice crossing with Ai14 mice),we demonstrate that lineage-traced astrocytes can be successfully converted into NeuNpositive neurons after expressing NeuroD1 through adeno-associated viruses.Retroviral expression of NeuroD1 further confirms that dividing glial cells can be converted into neurons.Importantly,we demonstrate that for in vivo cell conversion study,using a safe level of adeno-associated virus dosage(10^10–10^12 gc/mL,1μL)in the rodent brain is critical to avoid artifacts caused by toxic dosage,such as that used in a recent bioRxiv study(2×10^13 gc/mL,1μL,mouse cortex).For therapeutic purpose under injury or diseased conditions,or for non-human primate studies,adeno-associated virus dosage needs to be optimized through a series of dose-finding experiments.Moreover,for future in vivo gliato-neuron conversion studies,we recommend that the adeno-associated virus results are further verified with retroviruses that mainly express transgenes in dividing glial cells in order to draw solid conclusions.The study was approved by the Laboratory Animal Ethics Committee of Jinan University,China(approval No.IACUC-20180330-06)on March 30,2018.展开更多
Since the generation of induced pluripotent stem cells in 2006, cellular reprogramming has attracted increasing attention as a revolutionary strategy for cell replacement therapy. Recent advances have revealed that so...Since the generation of induced pluripotent stem cells in 2006, cellular reprogramming has attracted increasing attention as a revolutionary strategy for cell replacement therapy. Recent advances have revealed that somatic cells can be directly converted into other mature cell types, which eliminates the risk of neoplasia and the generation of undesired cell types. Astrocytes become reactive and undergo proliferation, which hampers axon regeneration following injury, stroke, and neurodegenerative diseases. An emerging technique to directly reprogram astrocytes into induced neural stem cells （iNSCs） and induced neurons （iNs） by neural fate determinants brings potential hope to cell replacement therapy for the above neurological problems. Here, we discuss the development of direct reprogramming of various cell types into iNs and iNSCs, then detail astrocyte-derived iNSCs and iNs in vivo and in vitro. Finally, we highlight the unsolved challenges and opportunities for improvement.展开更多
基金supported in part by grants from the National Natural Science Foundation of China(No.81673093,No.82170227,No.91649113,No.82470165,No.82000121,No.31771640)the Jiangsu Science and Technology Department(No.SBK20200191)+1 种基金the State Key Laboratory of Radiation Medicine and Protection of Soochow University(No.GZC00201)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘The crosstalk between megakaryocytic lineage cells and the skeletal system has just begun to be explored but remains largely elusive.Using conditional gene knockout mouse models,we demonstrated that loss of Beclin 1(Becn1),a major regulator of mammalian autophagy,exclusively in the megakaryocytic lineage disrupted autophagy in platelets but did not compromise megakaryopoiesis or the formation and function of platelets.Unexpectedly,conditional Becn1 deletion in male mice led to a remarkable increase in bone mass with improved bone quality,in association with a decrease in sex hormone binding globulin(SHBG)and an increase in free testosterone(FT).In vivo Becn1 overexpression in megakaryocytic lineage-specific cells reduced bone mass and quality,along with an increase in SHBG and a decrease in FT.Transplantation of wild-type bone marrow cells into megakaryocytic lineage Becn1-deficient male mice restored bone mass and normalized SHBG and FT.Furthermore,bilateral orchiectomy of Becn1^(f/f);Pf4-iCre mice,which are crippled with the production of testosterone,resulted in a reduction in bone mass and quality,whereas in vivo overexpression of SHBG,specifically in the liver of Becn1^(f/f);Pf4-iCre mice,decreased FT and reduced bone mass and quality.In addition,metformin treatment,which induces SHBG expression,reduced FT and normalized bone mass in Becn1^(f/f);Pf4-iCre mice.We thus concluded that Becn1 of the megakaryocytic lineage is dispensable locally for platelet hemostasis but limits bone mass by increasing SHBG,which in turn reduces the FT of male mice.Our findings highlight a mechanism by which Becn1 from megakaryocytic lineage cells distally balances bone growth.
基金the financial support received from the National Natural Science Foundation of China(82202078)the National Social Science Foundation of China(23&ZD203)+4 种基金support for G.H.includes National Natural Science Foundation of China(82402203)the Open Project of the Key Laboratory of Forensic Genetics of the Ministry of Public Security(2022FGKFKT05)the Center for Archaeological Science of Sichuan University(23SASA01)the 1‧3‧5 Project for Disciplines of Excellence at West China Hospital,Sichuan University(ZYJC20002)the Sichuan Science and Technology Program(2024NSFSC1518).
文摘The reconstruction of demographic history using ancient and modern genomic resources reveals extensive interactions and admixture between ancient nomadic pastoralists and the social organizations of the Chinese Central Plain.However,the extent to which Y-chromosome genetic legacies from nomadic emperor-related ancestral lineages influence the Chinese paternal gene pool remains unclear.Here,we genotype 2717 ethnolinguistically diverse samples belonging to C2a lineages,perform whole-genome sequencing on 997 representative samples,and integrate these data with ancient genomic sequences.We reconstruct the evolutionary histories of Northern Zhou-,Qing emperor-,and pastoralist-related lineages to assess their genetic impact on modern Chinese populations.This reassembled fine-scale Ychromosome phylogeny identifies deep divergence and five Neolithic expansion events contributing differently to the formation of northern Chinese populations.Phylogeographic modeling indicates that the nomadic empires of the Northern Zhou and Qing dynasties genetically originated from the Mongolian Plateau.Phylogenetic topology and shared haplotype patterns show that three upstream ancestors of Northern Zhou(C2a1a1b1a2a1b-FGC28857),Donghu tribe(C2a1a1b1-F1756),and Qing(C2a1a3a2-F10283)emperor-related lineages expanded during the middle Neolithic,contributing significantly to genetic flow between ancient northeastern Asians and modern East Asians.Notably,this study reveals limited direct contributions of Emperor Wu of Northern Zhou’s lineages to modern East Asians.
基金supported by NIH grants NIH/NIA R01AG069401(to L.Q.)NIH/NHLBI U54HL165442(to K.T.)P30AR069619(to Penn Center for Musculoskeletal Disorders).
文摘Bone resorption by osteoclasts is a critical step in bone remodeling,a process important for maintaining bone homeostasis and repairing injured bone.We previously identified a bone marrow mesenchymal subpopulation,marrow adipogenic lineage precursors(MALPs),and showed that its production of RANKL stimulates bone resorption in young mice using Adipoq-Cre.To exclude developmental defects and to investigate the role of MALPs-derived RANKL in adult bone,we generated inducible reporter mice(Adipoq-CreER Tomato)and RANKL deficient mice(Adipoq-CreER RANKLflox/flox,iCKO).Single cell-RNA sequencing data analysis and lineage tracing revealed that Adipoq+cells contain not only MALPs but also some mesenchymal progenitors capable of osteogenic differentiation.In situ hybridization showed that RANKL mRNA is only detected in MALPs,but not in osteogenic cells.RANKL deficiency in MALPs induced at 3 months of age rapidly increased trabecular bone mass in long bones as well as vertebrae due to diminished bone resorption but had no effect on the cortical bone.Ovariectomy(OVX)induced trabecular bone loss at both sites.RANKL depletion either before OVX or at 6 weeks post OVX protected and restored trabecular bone mass.Furthermore,bone healing after drill-hole injury was delayed in iCKO mice.Together,our findings demonstrate that MALPs play a dominant role in controlling trabecular bone resorption and that RANKL from MALPs is essential for trabecular bone turnover in adult bone homeostasis,postmenopausal bone loss,and injury repair.
基金Supported by the National Research Foundation of Korea Grant Funded by the Korea Government,No.RS-2024-00440477the Korea Institute of Science and Technology Institutional Program,No.2E33111-24-042.
文摘BACKGROUND Mixed lineage kinase domain-like protein(MLKL)serves as a critical mediator in necroptosis,a form of regulated cell death linked to various liver diseases.This study aims to specifically investigate the role of MLKL’s adenosine triphosphate(ATP)-binding pocket in facilitating necroptosis-independent pathways that may contribute to liver disease progression.By focusing on this mechanism,we seek to identify potential therapeutic targets that can modulate MLKL activity,offering new strategies for the prevention and treatment of liver-related pathologies.AIM To investigate the possibility of using the ATP-binding pocket-associated,necro-ptosis-independent MLKL pathway as a target for liver diseases.METHODS Cell death following necroptosis stimuli was evaluated using cell proliferation assays,flow cytometry,and electron microscopy in various cells.The human liver organoid system was used to evaluate whether the MLKL ATP pocket-binding inhibitor could attenuate inflammation.Additionally,alcoholic and non-alcoholic fatty liver diseases animal models were used to determine whether MLKL ATP pocket inhibitors could attenuate liver injury.RESULTS While an MLKL ATP pocket-binding inhibitor did not prevent necroptosis-induced cell death in RAW 264.7 cells,it did reduce the necroptosis-led expression of CXCL2,ICAM,and VCAM.Notably,MLKL ATP pocket inhibitor diminishes the expression of CXCL2,ICAM,and VCAM by inhibiting the IκB kinase and nuclear factor kappa-B pathways without inducing necroptosis-induced cell death in two-dimensional cell culture as well as the human-derived liver organoid system.Although MLKL ATP-binding inhibitor was ineffective in non-alcoholic fatty liver disease animal models,MLKL ATP-binding inhibitor attenuated hepatic inflammation in the alcoholic liver disease model.CONCLUSION MLKL ATP pocket-binding inhibitor exerted anti-inflammatory effects through the necroptosis-independent MLKL pathway in an animal model of alcoholic liver disease.
文摘Based on the study of two Early Pleistocene human skulls found in Yunxian County,Hubei Province,China,Ji et al.(2024)suggested that Homo orientalis was the common ancestor of the sapiens lineage and the longi lineage,and proposed that both the two lineages originated from East Asia.We further proposed that Genus Homo should be divided into two subgenera:Subgenus Homo and Subgenus Parahomo.All members of the sapiens lineage would be assigned to Subgenus Homo,and all members of the longi lineage would be grouped into Subgenus Parahomo.Homo(Parahomo)heidelbergensis and Homo(Parahomo)neanderthalensis also were the members of the longi lineage,an evolutionary branch spreaded from East Asia to Africa and Europe more than 600,000 years ago.This paper mainly makes an introduction to the speciation,classification and phylogeny of the longi lineage.The longi lineage and the sapiens lineage are″sister group″relationship,but the longi lineage is an extinct lineage,having nothing to do with our modern people.
基金Supported by the Science and Technology Planning Projects of Guizhou Province,No.QKHJC-ZK[2022]YB642Health Research Project of Guizhou Province,No.gzwkj2024-324,and No.gzwkj2024-103+2 种基金WBE Liver Fibrosis Foundation,No.CFHPC2025028Beijing Liver and Gallbladder Mutual Aid Public Welfare Foundation Artificial Liver Special Fund,No.iGandanF-1082024-Rgg018Student Innovation and Entrepreneurship Training Program of Zunyi Medical University,No.S2024106612360.
文摘In this letter,we comment on the article by Xuan Yuan et al,published in the recent issue of the World Journal of Gastroenterology.Mixed lineage kinase domainlike protein(MLKL)exhibits cell-type-specific functions in liver parenchymal and non-parenchymal cells,playing dual roles in the pathogenesis of liver diseases.In hepatocytes,MLKL primarily mediates necroptosis and inhibits autophagy,thereby exacerbating liver injury.Conversely,in non-parenchymal liver cells,MLKL modulates inflammatory responses and promotes fibrotic processes,thereby driving disease progression.Notably,MLKL also demonstrates protective functions under specific conditions.For instance,MLKL can inhibit intracellular bacterial replication,promote endosomal trafficking,and facilitate the generation and release of extracellular vesicles,potentially exerting hepatoprotective effects.Understanding these cell-type-specific mechanisms of MLKL action,including its dual roles in promoting injury and providing protection,is crucial for elucidating the complex pathogenesis of liver diseases and developing targeted therapeutic strategies.
文摘Although mixed lineage kinase domain-like protein(MLKL)is widely recognized as a critical effector in the necroptotic signaling pathway,MLKL plays broader regulatory roles beyond programmed necroptosis.Notably,Xuan Yuan et al demonstrated that CPD4,an ATP-binding pocket inhibitor of MLKL,significantly reduces liver inflammation and improves liver function by inhibiting NF-κB signaling,suggesting its use as a potential therapeutic candidate for alcoholic liver disease.However,the pharmacokinetic properties and long-term toxicity of CPD4 require further evaluation.Moreover,a single therapeutic strategy targeting MLKL may not be sufficient.Future studies should focus on the precise regulation of MLKL and develop combination therapies to achieve dual intervention of inflammatory and cell death pathways.This paper provides an important theoretical foundation for translational research on MLKL-targeted therapy.However,its clinical translation requires overcoming existing limitations and further elucidating the regulatory network of MLKL in complex microenvironments.
基金supported by the National Natural Science Foundation of China(No.82322075)。
文摘Objective:Ulcerative colitis is closely associated with intestinal stem cell(ISC)loss and impaired intestinal mucus barrier.Sinisan(SNS),a compound Chinese herbal medicine,has a long history in the treatment of intestinal dysfunction,yet whether SNS can relieve acute experimental colitis by modulating ISC proliferation and secretory cell differentiation has not been studied.Our study tested the effect of SNS against acute colitis and focused on the mechanisms involving intestinal barrier recovery.Methods:Network pharmacology analysis and blood entry component analysis of SNS were used to explore the underlying mechanism by which SNS affects the acute dextran sulfate sodium(DSS)-induced murine colitis model.RNA-sequencing was used to demonstrate the mechanism.Further,reverse transcription-quantitative polymerase chain reaction,immunofluorescence staining,and alcian blue and periodic acid-Schiff staining were performed in vivo and in the colonic organoids to investigate the cell lineage differentiation-related mechanism of SNS.Furthermore,potential active ingredients from SNS were predicted by network pharmacology analysis.Results:SNS dramatically suppressed DSS-induced acute colonic inflammation in mice.RNA-sequencing analysis revealed downregulation of inflammation and apoptosis-related genes,and upregulation of lipid metabolism and proliferation-related genes,such as Irf7,Ppara,Clspn and Hspa5.Additionally,ISC renewal and intestinal secretory cell lineage commitment were significantly promoted by SNS both in vivo and in vitro in colonic organoids,leading to enhanced mucin expression.Furthermore,potential active ingredients from SNS that mediated inflammation,lipid metabolism,proliferation,apoptosis,stem cells and secretory cells were predicted using a network pharmacology approach.Conclusion:Our study shed light on the underlying mechanism of SNS in attenuating acute colitis from the perspective of ISC renewal and secretory lineage cell differentiation,suggesting a of novel therapeutic strategy against colitis.
基金supported by Institute of Laboratory Animal Sciences,Chinese Academy of Medical Sciences and Comparative Medicine Center,Peking Union Medical College,Collaborative Innovation Program of the Chinese Academy of Sciences(22SH19)Nonprofit Central Research Institute Fund of Chinese Academy of Medical Sciences(2023-PT180-01).
文摘Cell lineage tracing is a key technology for describing the developmental history of individual progenitor cells and assembling them to form a lineage development tree.However,traditional methods have limitations of poor stability and insufficient reso-lution.As an efficient and flexible gene editing tool,CRISPR-Cas9 system has been widely used in biological research.Furthermore,CRISPR-Cas9 gene editing-based tracing methods can introduce fluorescent proteins,reporter genes,or DNA barcodes for high-throughput sequencing,enabling precise lineage analysis,significantly im-proving precision and resolution,and expanding its application range.In this review,we summarize applications of CRISPR-Cas9 system in cell lineage tracing,with special emphasis on its successful applications in traditional model animals(e.g.,zebrafish and mice),large animal models(pigs),and human cells or organoids.We also discussed its potential prospects and challenges in xenotransplantation and regenerative medicine.
基金supported by the National Key R&D Program of China(2021YFA1302500 and 2021YFA1302501)the National Natural Science Foundation of China(32293190,32293191,31970570,and 32200492).
文摘Unraveling the lineage relationships of all descendants from a zygote is fundamental to advancing our understanding of developmental and stem cell biology.However,existing cell barcoding technologies in zebrafish lack the resolution to capture the majority of cell divisions during embryogenesis.A recently developed method,a substitution mutation-aided lineage-tracing system(SMALT),successfully reconstructed high-resolution cell phylogenetic trees for Drosophila melanogaster.Here,we implement the SMALT system in zebrafish,recording a median of 14 substitution mutations on a one-kilobase-pair barcoding sequence for one-day post-fertilization embryos.Leveraging this system,we reconstruct four cell lineage trees for zebrafish fin cells,encompassing both original and regenerated fin.Each tree consists of hundreds of internal nodes with a median bootstrap support of 99%.Analysis of the obtained cell lineage trees reveals that regenerated fin cells mainly originate from cells in the same part of the fins.Through multiple times sampling germ cells from the same individual,we show the stability of the germ cell pool and the early separation of germ cell and somatic cell progenitors.Our system offers the potential for reconstructing high-quality cell phylogenies across diverse tissues,providing valuable insights into development and disease in zebrafish.
基金supported by the National Natural Science Foundation of China(32202788)the Special Research Fund of Shanxi Agricultural University for High-level Talents,China(2021XG004)+3 种基金the Fund for Shanxi“1331 Project”,China(20211331-13)the Shanxi Province Excellent Doctoral Work Award-Scientific Research Project,China(SXBYKY2021063,SXBYKY2021005,and SXBYKY 2022014)the earmarked fund for Modern Agro-industry Technology Research System of Shanxi Province,China(2023CYJSTX15-13)the Fundamental Research Program of Shanxi Province,China(202103021224156)。
文摘Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.
基金supported by the National Key Research&Development Program of China(2021YFA0805100,2023YFA1800700,2019YFA0110403,2019YFA0802000)the National Science Foundation of China(82088101,32370885,92368103,32370897)the Westlake Education Foundation,and the Benyuan Charity Fund,Research Funds of Hangzhou Institute for Advanced Study(2022ZZ01015 and B04006C01600515)。
文摘Genetic lineage tracing has been widely employed to investigate cell lineages and fate.However,conventional reporting systems often label the entire cytoplasm,making it challenging to discern cell boundaries.Additionally,single Cre-lox P recombination systems have limitations in tracing specific cell populations.This study proposes three reporting systems utilizing Cre,Dre,and Dre+Cre mediated recombination.These systems incorporate td Tomato expression on the cell membrane and Phi YFP expression within the nucleus,allowing for clear observation of the nucleus and membrane.The efficacy of these systems is successfully demonstrated by labeling cardiomyocytes and hepatocytes.The potential for dynamic visualization of the cell membrane is showcased using intravital imaging microscopy or threedimensional imaging.Furthermore,by combining this dual recombinase system with the Pro Tracer system,hepatocyte proliferation is traced with enhanced precision.This reporting system holds significant importance for advancing the understanding of cell fate studies in development,homeostasis,and diseases.
基金supported by the Key Science & Technology Project of Gansu Province (22ZD6NA007)the National Key Research and Development Program of China (2021YFD2200202)Computing support was provided by the Supercomputing Center of Lanzhou University
文摘The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and diversification.Much can be learned about this process from phylogeny-based trait evolution.However,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear discordant.Here,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium subg.Cyathophora.Both concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS distribution.However,GTD was high across the genomes of subg.Cyathophora:~27%e38.9%of the SCG trees were in conflict with the species tree.Plasmid and nuclear incongruence was also present.Our coalescent simulations indicated that such GTD was mainly a product of ILS.Our hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the subg.Cyathophora phylogeny may have caused the character transition,as well as the anomalous cpDNA tree.Our study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.
基金supported by the National Key Research and Development Program of China(2021YFF1200904,2021YFA1302500 to J.-R.Y.)the National Natural Science Foundation of China(32122022,31871320 to J.-R.Y.)by Science and Technology Planning Project of Guangdong Province,China(2014A030304053 to X.Z.).
文摘In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in developmental biology and other related fields.Recent technological advancements,especially those in editable genomic barcodes and single-cell high-throughput sequencing,have sparked a new wave of experimental methods for reconstructing CLTs.Here we review the existing experimental approaches to the reconstruction of CLT,which are broadly categorized as either image-based or DNA barcode-based methods.In addition,we present a summary of the related literature based on the biological insight pro-vided by the obtained CLTs.Moreover,we discuss the challenges that will arise as more and better CLT data become available in the near future.Genomic barcoding-based CLT reconstructions and analyses,due to their wide applicability and high scalability,offer the potential for novel biological discoveries,especially those related to general and systemic properties of the developmental process.
基金financially supported by the National Natural Science Foundation of China(Grant No.32060310)a grant from the Department of Education of Guangxi.
文摘The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variation.In this study,69 mitogenomes of the Black-throated Tit(Aegithalos concinnus)were assembled and annotated from a large number of short reads generated using high-throughput sequencing technology.Comparative analyses revealed that mitogenomic characteristics such as length,gene and nucleotide composition,codon usage,and duplicated control regions were relatively conserved despite substantial intraspecies morphological changes.Yet,all the individuals from the subspecies A.c.iredalei had one more nucleotide in the 12S rRNA than the other studied subspecies.Phylogenetic analyses showed five distinct lineages based on the complete mitogenomes and the 13 combined protein-coding genes,whereas only four lineages were observed when using the duplicate control regions.Most interestingly,each lineage had both copies of the control regions of the comprising individuals,indicating that the paralogous control regions were more similar than the orthologous sequences from the distinct lineages.This suggested the control regions had undergone concerted evolution.The Black-throated Tit has complex evolutionary history and needs further investigating the taxonomic status of these lineages,as well as the underlying evolutionary processes.Our findings call for more research on intraspecies mitogenomic variation.
基金supported by grants from Key Research&Development Project of Nanhua Biomedical Co.,Ltd.(No.H202191490139)National Natural Science Foundation of China(No.31872866)+1 种基金China Postdoctoral Science Foundation(Nos.2021M701160 and 2022M721101)Funds of Hunan university(521119400156).
文摘Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the pathogen responsible for coronavirus disease 2019(COVID-19),continues to evolve,giving rise to more variants and global reinfections.Previous research has demonstrated that barcode segments can effectively and cost-efficiently identify specific species within closely related populations.In this study,we designed and tested RNA barcode segments based on genetic evolutionary relationships to facilitate the efficient and accurate identification of SARS-CoV-2 from extensive virus samples,including human coronaviruses(HCoVs)and SARSr-CoV-2 lineages.Nucleotide sequences sourced from NCBI and GISAID were meticulously selected and curated to construct training sets,encompassing 1733 complete genome sequences of HCoVs and SARSr-CoV-2 lineages.Through genetic-level species testing,we validated the accuracy and reliability of the barcode segments for identifying SARS-CoV-2.Subsequently,75 main and subordinate species-specific barcode segments for SARS-CoV-2,located in ORF1ab,S,E,ORF7a,and N coding sequences,were intercepted and screened based on single-nucleotide polymorphism sites and weighted scores.Post-testing,these segments exhibited high recall rates(nearly 100%),specificity(almost 30%at the nucleotide level),and precision(100%)performance on identification.They were eventually visualized using one and two-dimensional combined barcodes and deposited in an online database(http://virusbarcodedatabase.top/).The successful integration of barcoding technology in SARS-CoV-2 identification provides valuable insights for future studies involving complete genome sequence polymorphism analysis.Moreover,this cost-effective and efficient identification approach also provides valuable reference for future research endeavors related to virus surveillance.
基金This study was supported by the National Natural Science Foundation of China(No.U1801681,to GC and No.31970906,to WL)Guangdong Science and Technology Department(‘Key technologies for treatment of brain disorders’,No.2018B030332001,to GC)+2 种基金the Natural Science Foundation of Guangdong Province of China(No.2020A1515011079,to WL and No.2020A1515010854,to QW)the internal funding from Jinan University(No.21616110,to GC)the Young Scientists Fund of the National Natural Science Foundation of China(No.31701291,to WL).
文摘Regenerating functional new neurons in the adult mammalian central nervous system has been proven to be very challenging due to the inability of neurons to divide and repopulate themselves after neuronal loss.Glial cells,on the other hand,can divide and repopulate themselves under injury or diseased conditions.We have previously reported that ectopic expression of NeuroD1 in dividing glial cells can directly convert them into neurons.Here,using astrocytic lineage-tracing reporter mice(Aldh1l1-CreERT2 mice crossing with Ai14 mice),we demonstrate that lineage-traced astrocytes can be successfully converted into NeuNpositive neurons after expressing NeuroD1 through adeno-associated viruses.Retroviral expression of NeuroD1 further confirms that dividing glial cells can be converted into neurons.Importantly,we demonstrate that for in vivo cell conversion study,using a safe level of adeno-associated virus dosage(10^10–10^12 gc/mL,1μL)in the rodent brain is critical to avoid artifacts caused by toxic dosage,such as that used in a recent bioRxiv study(2×10^13 gc/mL,1μL,mouse cortex).For therapeutic purpose under injury or diseased conditions,or for non-human primate studies,adeno-associated virus dosage needs to be optimized through a series of dose-finding experiments.Moreover,for future in vivo gliato-neuron conversion studies,we recommend that the adeno-associated virus results are further verified with retroviruses that mainly express transgenes in dividing glial cells in order to draw solid conclusions.The study was approved by the Laboratory Animal Ethics Committee of Jinan University,China(approval No.IACUC-20180330-06)on March 30,2018.
基金supported by a grant from Department of Neurology, Zhujiang Hospital, Southern Medical Universityl, China (2014257)
文摘Since the generation of induced pluripotent stem cells in 2006, cellular reprogramming has attracted increasing attention as a revolutionary strategy for cell replacement therapy. Recent advances have revealed that somatic cells can be directly converted into other mature cell types, which eliminates the risk of neoplasia and the generation of undesired cell types. Astrocytes become reactive and undergo proliferation, which hampers axon regeneration following injury, stroke, and neurodegenerative diseases. An emerging technique to directly reprogram astrocytes into induced neural stem cells （iNSCs） and induced neurons （iNs） by neural fate determinants brings potential hope to cell replacement therapy for the above neurological problems. Here, we discuss the development of direct reprogramming of various cell types into iNs and iNSCs, then detail astrocyte-derived iNSCs and iNs in vivo and in vitro. Finally, we highlight the unsolved challenges and opportunities for improvement.
