The Roles of PRRC2A in Self-renewal and Differentiation Potentials of Human Induced Pluripotent Stem Cells

Abstract

Stem cells are undifferentiated cells with self-renewal and differentiation potential. They are destined differentiate into various cell types with diverse functions. Stem cells are classified according to their origin and ability, and include embryonic (ES) cells and adult stem cells, and then in 2006, new pluripotent stem cells, iPSCs (induced pluripotent stem cells) were established. By using these stem cells, many studies have been done to discover what factors are involved in the determination of cell fate, self-renewal, and cell differentiation. We targeted PRRC2A, which is one of the PRRC (the proline-rich and coiled-coil–containing) proteins, since little is known about the functions of this family. We took a loss-of-function approach in human iPSCs, using the CRISPRi system to knockdown PRRC2A and generated PRRC2A knockdown iPSCs (PRRC2A KD iPSCs). This cell line showed good knockdown of PRRC2A, demonstrating that the CRISPRi system efficiently and precisely knocked down the target gene. The PRRC2A KD iPSCs displayed atypical morphological characteristics of pluripotent stem cells, and their number decreased dramatically, indicating the possibility that PRRC2A plays in cell self-renewal. However, PRRC2A KD iPSCs successfully differentiated into three germ layers including neural cells, suggesting that PRRC2A is not required for pluripotency. Therefore, we conclude that PRRC2A plays a role in self-renewal but not in differentiation of iPSCs.