title: Myogenic differentiation of p53- and Rb-deficient immortalized and transformed bovine fibroblasts in response to MyoD.
abstract: We have established in culture a spontaneously immortalized bovine embryonic fibroblast (BEF) cell line that has lost p53 and p16(INK4a) functions. MyoD is a muscle-specific regulator capable of inducing myogenesis in a number of cell types. When the BEF cells were transduced with MyoD they differentiated efficiently to desmin-positive myofibers in the presence of 2% horse serum and 1.7 nM insulin. The myogenic differentiation of this cell line was more rapid and obvious than that of C2C12 cells, as judged by morphological changes and expression of various muscle regulatory factors. To confirm that lack of the p53 and p16(INK4a) pathway does not prevent MyoD-mediated myogenesis, we established a cell line transformed with SV40LT (BEFV) and introduced MyoD into it. In the presence of 2% horse serum and 1.7 nM insulin, the MyoD-transduced BEFV cells differentiated like the MyoD-transduced BEFS cells, and displayed a similar pattern of expression of muscle regulatory proteins. Taken together, our results indicate that MyoD overexpression overcomes the defect in muscle differentiation associated with immortalization and cell transformation caused by the loss of p53 and Rb functions.
authors: Laboratory of Cell Growth and Function Regulation, Korea University, Seoul 136-701, Korea.
authors: Xun
authors: X
authors: Jin
authors: Joong-Seub
authors: JS
authors: Lee
authors: Sungwook
authors: S
authors: Kwak
authors: Ji-Eun
authors: JE
authors: Jung
authors: Tae-Kyung
authors: TK
authors: Kim
authors: Chenxiong
authors: C
authors: Xu
authors: Zhongshan
authors: Z
authors: Hong
authors: Zhehu
authors: Z
authors: Li
authors: Sun-Myoung
authors: SM
authors: Kim
authors: Kwang Youn
authors: KY
authors: Whang
authors: Ki-Chang
authors: KC
authors: Hong
authors: Seungkwon
authors: S
authors: You
authors: Yun-Jaie
authors: YJ
authors: Choi
authors: Hyunggee
authors: H
authors: Kim