Retinoblastoma 1 (RB1) modulates the proliferation of chicken preadipocytes

Abstract

Retinoblastoma 1 (RB1) has been extensively studied in mammalian species, but its function in avian species is unclear. The objective of this study was to reveal the role of chicken RB1 (Gallus gallus RB1, gRB1) in the proliferation of preadipocytes. In the current study, quantitative real-time PCR analysis showed that the expression levels of gRB1 transiently increased during the proliferation of preadipocytes. The MTT assay showed that gRB1 overexpression suppressed preadipocyte proliferation, and gRB1 interference promoted preadipocyte proliferation. Additionally, cell-cycle analysis indicated that gRB1 may play a crucial role in the G1/S transition. Consistently, gene expression analysis showed that gRB1 knockdown promoted marker of proliferation Ki-67 (MKi67) expression at 96 h (P < 0.05), and that overexpression of gRB1 reduced MKi67 expression at 72 h (P < 0.05). Together, our study demonstrated that gRB1 inhibited preadipocyte proliferation at least in part by inhibiting the G1 to S phase transition.