Islet-1(Isl1),a LIM homeodomain protein,is expressed in the embryonic pancreatic epithelium.As a key transcription factor,Isl1 can not only regulate insulin gene expression in normal glucose condition but also maintai...Islet-1(Isl1),a LIM homeodomain protein,is expressed in the embryonic pancreatic epithelium.As a key transcription factor,Isl1 can not only regulate insulin gene expression in normal glucose condition but also maintainβ-cell function and impact pancreaticβ-cell target genes.Some experiments have suggested that Micro RNA(miRNA)can play a critical role during the induction of insulinproducing cells(IPCs).However,it is unclear whether miRNA may regulate Isl1 expression during differentiation of human umbilical cord mesenchymal stem cells(HUMSCs)into IPCs.In this investigation,we induced HUMSCs into IPCs with a modified two-step protocol,activin A,retinoic acid(step1)and conophylline,nicotinamide(step2).To find the miRNA regulating Isl1 expression,we respectively used Target Scan,miRDB and RNAhybrid to predict and got the result,miR-128 and miR-216a.The miRNAs can inhibit Isl1 expression by dual luciferase assay.The results of real-time Polymerase Chain Reaction(PCR)showed that Isl1 expression level was almost reciprocal to that of miR-128 and miR-216a during differentiation of HUMSCs into IPCs.Furthermore,over-expression of miR-128 or miR-216a downregulated expression levels of Isl1 and Maf A.Therefore,miR-128 or miR-216a may regulate expression of islet-specific transcription factors to control differentiation of HUMSCs into IPCs.展开更多
基金Supported by Liaoning Province Education Administration Funded Program of China(LJKZ1374)。
文摘Islet-1(Isl1),a LIM homeodomain protein,is expressed in the embryonic pancreatic epithelium.As a key transcription factor,Isl1 can not only regulate insulin gene expression in normal glucose condition but also maintainβ-cell function and impact pancreaticβ-cell target genes.Some experiments have suggested that Micro RNA(miRNA)can play a critical role during the induction of insulinproducing cells(IPCs).However,it is unclear whether miRNA may regulate Isl1 expression during differentiation of human umbilical cord mesenchymal stem cells(HUMSCs)into IPCs.In this investigation,we induced HUMSCs into IPCs with a modified two-step protocol,activin A,retinoic acid(step1)and conophylline,nicotinamide(step2).To find the miRNA regulating Isl1 expression,we respectively used Target Scan,miRDB and RNAhybrid to predict and got the result,miR-128 and miR-216a.The miRNAs can inhibit Isl1 expression by dual luciferase assay.The results of real-time Polymerase Chain Reaction(PCR)showed that Isl1 expression level was almost reciprocal to that of miR-128 and miR-216a during differentiation of HUMSCs into IPCs.Furthermore,over-expression of miR-128 or miR-216a downregulated expression levels of Isl1 and Maf A.Therefore,miR-128 or miR-216a may regulate expression of islet-specific transcription factors to control differentiation of HUMSCs into IPCs.
