Study On The Transcriptional Activation And Function Of NOVA1 During The Adipogenesis Of Adipose Tissue-derived Stem Cells

BackgroudsRNA binding protein Nova-1(neuro-oncological ventral antigen 1)is a neural specific splicing factor.It has been found that Nova-1 would affect prognosis of tumor,metabolism of energy and is also highly expressed in adipose tissue.In the process of studying Adipose tissue-derived stem cells(ADSCs)for adipocyte differentiation,we found that the expression of NOVA1 increased continuously during Adipose tissue-derived stem cells(ADSCs)adipogenesis,and knockingdown NOVA1 would significantly affect inhibit adipogenesis.Our study will further explore the activation mechanism of NOVA1 during ADSCs adipogenesis and the mechanism of Noval in regulation adipogenesis.Objectives1.To explore the regulation of adipose-specific transcription factors on NOVA1.2.To find out the target of Noval in regulating ADSCs adipogenesis.Methods and Results1.The regulation of adipose-specific transcription factors on NOVA1.Methods:Using dual luciferse reporter assay system to examine the effect of adipocyte-specific transcription factors on NOVA1 promoter.We performed ChIP assay in the ADSCs to examine enrichment of PPARy on NOVA1 promoter.We used real-time quantitative PCR to examine the mRNA expression of NOVA1 in ADSCs treated with PPARy activator or overexpressing PPARy proteins.Results:Only PPARy:RXRa transcription factor complex could promote the transcription of NOVA1 promoter,the transcriptional activation denpended on Peroxisome Prolifertors Responsive Element(PPRE)in the NOVA1 promoter.PPARy was significantly enriched in the region near PPRE on the NOVA1 promoter.The mRNA level of NOVA1 was increased in ADSCs treated with PPARy activator or overexpressing PPARy proteins,but PPARy inhibitor or inactivated PPARy would eliminate the increasion.2.The target of Noval in regulating ADSCs adipogenesis.Methods:Using transcriptome chip,bioinformatics analysis and real-time quantitative PCR to screen adipose-specific genes regulated by Noval.Knockingdown targrt gene and inducing adipogenesis.Using real-time quantitative PCR to detect the effects on ADSCs adipogenesis.Overexpress targrt gene on the basis of Knockdown NOVA1,then induce adipogenesis.Using oil red O and real-time quantitative PCR to detect the effects on ADSCs adipogenesis.Results:Noval could regulate the expression of ACSLl,CD36,FABP4,FASN and PLINI,Which were PPAR y target genes.Koncking-down CD36,FASN and PLINI can inhibit ADSCs adipogenesis.The overexpression of FASN or PLINI could partially rescue the inhibition of Noval on ADSCs adipogenesis.Conclusions1.The PPARy:RXRa transcription factor complex could transcriptional promotes the expression of NOVA1 gene.2.Noval affects ADSCs adipogenesis by regulating the expression of FASN and PLINI.