Human embryonic stem cells(hESCs)can be classified as having naive and primed pluripotency states.While several studies have reported different gene expression networks between these two pluripotency states,the role o...Human embryonic stem cells(hESCs)can be classified as having naive and primed pluripotency states.While several studies have reported different gene expression networks between these two pluripotency states,the role of alternative splicing(AS)in regulating these differences has not been well characterized.In this study,we performed RNA sequencing and identified differential AS events in 784 genes between naive and primed hESCs.Among these,KIAA1522,whose function has not been well studied,has state-specific isoforms regulated by alternative first exon(AFE).This splicing event resulted in isoforms with distinct N-terminal domains and subcellular localization.Notably,the sequences and alternative isoform patterns of KIAA1522 were conserved between humans and mice.Further investigation using cleavage under targets and tagmentation(CUT&Tag)experiments in cells with specific-isoform overexpression or knockdown revealed the opposite activity of long terminal repeat retrotransposons(LTR-RTs)and motif enrichment profiles.The naive-specific(N-P)isoform upregulated naive marker gene expression and preferentially activated LTR-RTs by binding to the motifs enriched for POU and FOX family transcription factor binding sites.Conversely,the primed-specific(P-P)isoform promoted primed marker gene expression and suppressed LTR-RTs activity by binding to the motifs enriched for zinc finger protein binding sites.Collectively,KIAA1522 regulates the balance between naive and primed pluripotency states through isoform-specific regulation of LTR-RTs activity and collaboration with distinct transcriptional regulators.In summary,our results characterize the splicing atlas of hESCs in naive and primed states and reveal the regulatory function and mechanism of AFE usage by KIAA1522.展开更多
目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在...目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在三维培养体系中可检测细胞的侵袭性及细胞与基质的相互作用。BMP4途径通过去除外源性成纤维细胞生长因子及提高氧含量均可促进BMP4诱导TB的分化。虽然hESC分化TB模型目前还存在一些争议,但是相关研究可为探讨人类胚胎的植入及胎盘的形成提供重要的理论依据。展开更多
Air pollution has been linked to many health issues,including skin conditions,especially in children.Among all the atmospheric pollutants,ultrafine particles have been deemed very dangerous since they can readily pene...Air pollution has been linked to many health issues,including skin conditions,especially in children.Among all the atmospheric pollutants,ultrafine particles have been deemed very dangerous since they can readily penetrate the lungs and skin,and be absorbed into the bloodstream.Here,we employed a human embryonic stem cell(h ESC)-based differentiation system towards keratinocytes,to test the effects of ultrafine carbon particles,which mimic ambient ultrafine particles,at environment related concentrations.We found that10 ng/mL to 10μg/mL ultrafine carbon particles down-regulated the expression of the pluripotency marker SOX2 in h ESCs.Moreover,1μg/mL to 10μg/mL carbon particle treatments disrupted the keratinocyte differentiation,and up-regulated inflammationand psoriasis-related genes,such as IL-1β,IL-6,CXCL1,CXCL2,CXCL3,CCL20,CXCL8,and S100 A7 and S100 A9,respectively.Overall,our results provide a new insight into the potential developmental toxicity of atmospheric ultrafine particles.展开更多
基金supported by the National Key Research and Development Program of China(2023YFA1802000,2022YFA1104100,2018YFA0109700,2018YFE0201102,2019YFA0110000)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16010503)+4 种基金the Youth Innovation Promotion Association,CAS(Y2023020)the National Natural Science Foundation of China(62127811)Strategic Collaborative Research Program of the Ferring Institute of Reproductive Medicine,Ferring Pharmaceuticals,Chinese Academy of Sciences(FIRMD181101)Informatization Plan of Chinese Academy of Sciences(CAS-WX2021SF-0101)Initiative Scientific Research Program,Institute of Zoology,Chinese Academy of Sciences(2023IOZ0302)。
文摘Human embryonic stem cells(hESCs)can be classified as having naive and primed pluripotency states.While several studies have reported different gene expression networks between these two pluripotency states,the role of alternative splicing(AS)in regulating these differences has not been well characterized.In this study,we performed RNA sequencing and identified differential AS events in 784 genes between naive and primed hESCs.Among these,KIAA1522,whose function has not been well studied,has state-specific isoforms regulated by alternative first exon(AFE).This splicing event resulted in isoforms with distinct N-terminal domains and subcellular localization.Notably,the sequences and alternative isoform patterns of KIAA1522 were conserved between humans and mice.Further investigation using cleavage under targets and tagmentation(CUT&Tag)experiments in cells with specific-isoform overexpression or knockdown revealed the opposite activity of long terminal repeat retrotransposons(LTR-RTs)and motif enrichment profiles.The naive-specific(N-P)isoform upregulated naive marker gene expression and preferentially activated LTR-RTs by binding to the motifs enriched for POU and FOX family transcription factor binding sites.Conversely,the primed-specific(P-P)isoform promoted primed marker gene expression and suppressed LTR-RTs activity by binding to the motifs enriched for zinc finger protein binding sites.Collectively,KIAA1522 regulates the balance between naive and primed pluripotency states through isoform-specific regulation of LTR-RTs activity and collaboration with distinct transcriptional regulators.In summary,our results characterize the splicing atlas of hESCs in naive and primed states and reveal the regulatory function and mechanism of AFE usage by KIAA1522.
文摘目前在体外研究中,主要通过分离胚体和骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)诱导这2种途径从人胚胎干细胞(hESC)分化获取滋养层细胞(TB)。胚体途径可基于细胞的黏附性和培养基中β-hCG的含量从胚体中分离获得TB,进而在三维培养体系中可检测细胞的侵袭性及细胞与基质的相互作用。BMP4途径通过去除外源性成纤维细胞生长因子及提高氧含量均可促进BMP4诱导TB的分化。虽然hESC分化TB模型目前还存在一些争议,但是相关研究可为探讨人类胚胎的植入及胎盘的形成提供重要的理论依据。
基金supported by the National Natural Science Foundation of China(Nos.21876197,21577166,21707160)the Chinese Academy of Sciences(Nos.XDB14040301,QYZDJSSW-DQC017)the K.C.Wong Education Foundation
文摘Air pollution has been linked to many health issues,including skin conditions,especially in children.Among all the atmospheric pollutants,ultrafine particles have been deemed very dangerous since they can readily penetrate the lungs and skin,and be absorbed into the bloodstream.Here,we employed a human embryonic stem cell(h ESC)-based differentiation system towards keratinocytes,to test the effects of ultrafine carbon particles,which mimic ambient ultrafine particles,at environment related concentrations.We found that10 ng/mL to 10μg/mL ultrafine carbon particles down-regulated the expression of the pluripotency marker SOX2 in h ESCs.Moreover,1μg/mL to 10μg/mL carbon particle treatments disrupted the keratinocyte differentiation,and up-regulated inflammationand psoriasis-related genes,such as IL-1β,IL-6,CXCL1,CXCL2,CXCL3,CCL20,CXCL8,and S100 A7 and S100 A9,respectively.Overall,our results provide a new insight into the potential developmental toxicity of atmospheric ultrafine particles.
