Primitive mammalian heart transforms from a single tube to a four-chambered muscular organ during a short developmental window.We found that knocking out global microRNA by deleting Dgcr8 microprocessor in Mespl cardi...Primitive mammalian heart transforms from a single tube to a four-chambered muscular organ during a short developmental window.We found that knocking out global microRNA by deleting Dgcr8 microprocessor in Mespl cardiovascular progenitor cells lead to the formation of extremely dilated and enlarged heart due to defective cardiomyocyte(CM)differentiation.Transcriptome analysis revealed unusual upregulation of vascular gene expression in Dgcr8 cKO hearts.Single cell RNA sequencing study further confirmed the increase of angiogenesis genes in single Dgcr8 cKO CM.We also performed global microRNA profiling of E9.5 heart for the first time,and identified that miR-541 was transiently highly expressed in E9.5 hearts.Interestingly,introducing miR-541 back into microRNA-free CMs partially rescued their defects,downregulated angiogenesis genes and significantly upregulated cardiac genes.Moreover,miR-541 can target Ctgf and inhibit endothelial function.Our results suggest that micro-RNAs are required to suppress abnormal angiogenesis gene program to maintain CM differentiation.展开更多
Background:Y-box binding protein 1(YB1 or YBX1)plays a critical role in tumorigenesis and cancer progression.However,whether YB1 affects malignant transformation by modulating non-codingRNAs remains largely unknown.Th...Background:Y-box binding protein 1(YB1 or YBX1)plays a critical role in tumorigenesis and cancer progression.However,whether YB1 affects malignant transformation by modulating non-codingRNAs remains largely unknown.This study aimed to investigate the relationship between YB1 and microRNAs and reveal the underlying mechanism by which YB1 impacts on tumor malignancy via miRNAs-mediated regulatory network.Methods:The biological functions of YB1 in hepatocellular carcinoma(HCC)cells were investigated by cell proliferation,wound healing,and transwell invasion assays.The miRNAs dysregulated by YB1 were screened by microarray analysis in HCC cell lines.The regulation of YB1 on miR-205 and miR-200b was determined by quantitative real-time PCR,dual-luciferase reporter assay,RNA immunoprecipitation,and pull-down assay.The relationships of YB1,DGCR8,Dicer,TUT4,and TUT1 were identified by pull-down and coimmunoprecipitation experiments.The cellular co-localization of YB1,DGCR8,and Dicer were detected by immunofluorescent staining.The in vivo effect of YB1 on tumor metastasis was determined by injecting MHCC97H cells transduced with YB1 shRNA or shControl via the tail vein in nude BALB/c mice.The expression levels of epithelial tomesenchymal transition markerswere detected by immunoblotting and immunohistochemistry assays.Results:YB1 promoted HCC cell migration and tumor metastasis by regulating miR-205/200b‒ZEB1 axis partially in a Snail-independent manner.YB1 suppressedmiR-205 and miR-200b maturation by interacting with the microprocessors DGCR8 and Dicer as well as TUT4 and TUT1 via the conserved cold shock domain.Subsequently,the downregulation of miR-205 and miR-200b enhanced ZEB1 expression,thus leading to increased cell migration and invasion.Furthermore,statistical analyses on gene expression data from HCC and normal liver tissues showed that YB1 expression was positively associated with ZEB1 expression and remarkably correlated with clinical prognosis.Conclusion:This study reveals a previously undescribed mechanism by which YB1 promotes cancer progression by regulating the miR-205/200b‒ZEB1 axis in HCC cells.Furthermore,these results highlight that YB1 may play biological functions via miRNAs-mediated gene regulation,and it can serve as a potential therapeutic target in human cancers.展开更多
基金the National Key R&D Program of China,grants 2017YFA0102802 and 2016YFC0900100 to J.Na and J.Wangthe National Natural Science Foundation of China(NSFC)grants 91740115,21675098 and 31471222 to J.Na,J.Wang and Y.Wang+1 种基金the National Basic Research Program of China,grant 2012CB966701 to J.Nathe funding from Tsinghua-Peking Center for Life Sciences and core facilities of Tsinghua-Peking Center for Life Sciences.
文摘Primitive mammalian heart transforms from a single tube to a four-chambered muscular organ during a short developmental window.We found that knocking out global microRNA by deleting Dgcr8 microprocessor in Mespl cardiovascular progenitor cells lead to the formation of extremely dilated and enlarged heart due to defective cardiomyocyte(CM)differentiation.Transcriptome analysis revealed unusual upregulation of vascular gene expression in Dgcr8 cKO hearts.Single cell RNA sequencing study further confirmed the increase of angiogenesis genes in single Dgcr8 cKO CM.We also performed global microRNA profiling of E9.5 heart for the first time,and identified that miR-541 was transiently highly expressed in E9.5 hearts.Interestingly,introducing miR-541 back into microRNA-free CMs partially rescued their defects,downregulated angiogenesis genes and significantly upregulated cardiac genes.Moreover,miR-541 can target Ctgf and inhibit endothelial function.Our results suggest that micro-RNAs are required to suppress abnormal angiogenesis gene program to maintain CM differentiation.
基金NationalNatural Science Foundation of China,Grant/Award Numbers:81672440,31701156,81972625DICP,Grant/Award Number:ZZBS201803The Construction of Liaoning CancerResearch Center,Grant/Award Number:1564992449013。
文摘Background:Y-box binding protein 1(YB1 or YBX1)plays a critical role in tumorigenesis and cancer progression.However,whether YB1 affects malignant transformation by modulating non-codingRNAs remains largely unknown.This study aimed to investigate the relationship between YB1 and microRNAs and reveal the underlying mechanism by which YB1 impacts on tumor malignancy via miRNAs-mediated regulatory network.Methods:The biological functions of YB1 in hepatocellular carcinoma(HCC)cells were investigated by cell proliferation,wound healing,and transwell invasion assays.The miRNAs dysregulated by YB1 were screened by microarray analysis in HCC cell lines.The regulation of YB1 on miR-205 and miR-200b was determined by quantitative real-time PCR,dual-luciferase reporter assay,RNA immunoprecipitation,and pull-down assay.The relationships of YB1,DGCR8,Dicer,TUT4,and TUT1 were identified by pull-down and coimmunoprecipitation experiments.The cellular co-localization of YB1,DGCR8,and Dicer were detected by immunofluorescent staining.The in vivo effect of YB1 on tumor metastasis was determined by injecting MHCC97H cells transduced with YB1 shRNA or shControl via the tail vein in nude BALB/c mice.The expression levels of epithelial tomesenchymal transition markerswere detected by immunoblotting and immunohistochemistry assays.Results:YB1 promoted HCC cell migration and tumor metastasis by regulating miR-205/200b‒ZEB1 axis partially in a Snail-independent manner.YB1 suppressedmiR-205 and miR-200b maturation by interacting with the microprocessors DGCR8 and Dicer as well as TUT4 and TUT1 via the conserved cold shock domain.Subsequently,the downregulation of miR-205 and miR-200b enhanced ZEB1 expression,thus leading to increased cell migration and invasion.Furthermore,statistical analyses on gene expression data from HCC and normal liver tissues showed that YB1 expression was positively associated with ZEB1 expression and remarkably correlated with clinical prognosis.Conclusion:This study reveals a previously undescribed mechanism by which YB1 promotes cancer progression by regulating the miR-205/200b‒ZEB1 axis in HCC cells.Furthermore,these results highlight that YB1 may play biological functions via miRNAs-mediated gene regulation,and it can serve as a potential therapeutic target in human cancers.
