Roles Of Ppar δ Interaction With GATA Family In Cardiac Differentiation Of P19CL6Cells

Background and PurposePeroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor super family which exist in three iso forms:PPARα、PPAR γ and PPAR β/δ. Previous studies showed that PPAR δ plays important roles in atherosclerosis, cell differentiation and myocardial energy metabolism. Cardiomyocyte-knockout PPARβ/δ in mice damages myocardial fatty acid oxidation, and leads to heart lipid accumulation and finally causes lipid-induced cardiac toxicity.The GATA family is a zinc finger transcription factor structure that comprises six members, the sequence they all bind to is (A/T) GATA (A/G). Previous studies have shown that GATA4and GATA6play key roles in heart development and myocardial cell proliferation, differentiation and apoptosis. Our laboratory studies have indicated that transcription factor GATA6recruits PPAR a to cooperatively activate Glut4gene expression which is the key gene in the myocardial energy metabolism. The energy metabolism of cardiac cells will be change when the cells are in differentiation. Due to the similarity between the structure and function of protein molecules on the same family members, we speculate whether PPAR δ interact with GATA4or GATA6to affect cell differentiation.Methods(1) We do a cells differentiation experiment to observe the effects on PPARδ, GATA4and GATA6alone or co-transfected P19CL6cells.(2) CO-IP (protein immunoprecipitation) A experiment to investigate whether PPARδ interactive with GATA4and GATA6in vivo.(3) Transient transfection By transfection to verify whether PPARδ interaction with GATA4and GATA6to cooperatively activate cardiac cell surface marker gene a-MHC promoter activity.Result(1) Experimental results show that PPARδ,GATA4and GATA6alone can significantly promote the differentiation process of myocardial cells, but the cells co-expressing PPAR8and GATA4, PPAR8and GATA6, the synergistic effects of cell differentiation is not obvious even inhibit the differentiation process P19CL6cells into cardiomyocytes.(2) CO-IP experiments showed that PPARδ and GATA4, GATA6combined with each other in vivo(3) Transient transfection experiments showed that PPARδ interaction with GATA4and GATA6to cooperatively activate cardiac cell surface marker gene α-MHC promoter activity.ConclusionPPARδ can interactive with GATA4and GATA6to affects the differentiation of P19CL6cells into cardiomyocytes.