| Abstract: | AIM: To explore whether YAP protein is important in induced pluripotent stem cell( i PSC)-induced cardiovascular progenitor cell and / or vascular smooth muscle differentiation. METHODS: Using episomal vector based reprogramming,we generated human i PSCs from donor fibroblasts. We used both this i PSCs and human H1 embryonic stem cells to differentiate into vascular smooth muscle cells(VSMCs) through cardiovascular progenitor cells(CVPC). Western blotting,q PCR and immunofluorescence microscopy were used to check the expression of YAP and related genes during this differentiation process. RESULTS: The results showed that i PSCs expressed pluripotent stem cell markers,such as Oct4,Nanog,Sox2,TRA-1-60 and SSEA3,and could form teratoma in SCID mice. YAP was highly expressed in pluripotent stem cells,but dramatically decreased when CVPC differentiation started. YAP gradually increased during CVPC three-day differentiation. The TAZ and YAP binding partner TEAD1,but not TEAD2 and TEAD4,have similar expression pattern in CVPC differentiation. Immunofluorescence result confirmed that YAP was activated and accumulated in nucleus. Interestingly,both YAP and phosphorylated YAP expression decreased to very low level after CVPC differentiated into VSMCs in 7 days. TEAD4 and TAZ also decreased,while TEAD1,TEAD2 and TEAD3 expression did not change during VSMC differentiation. CONCLUSION: YAP and TEAD1 expression increased during CVPC differentiation,while YAP and TEAD4 expression decreased from CVPC to VSMCs differentiation,which suggested YAP might have different function during diverse cell differentiation. |
