Ambrose M R, Bottazzi M E, Goodenow M M
Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, Gainesville 32610, USA.
DNA Cell Biol. 1995 Aug;14(8):701-7. doi: 10.1089/dna.1995.14.701.
Although the ski oncogene plays a role in cell proliferation, morphological transformation, and myogenic differentiation, the myogenic activities of the proto-oncogene c-ski have yet to be elucidated. c-ski is expressed within myoblasts during embryogenesis. Transcripts from the proto-oncogene can be detected in somites early in myogenic commitment, as well as in terminally differentiated skeletal muscle. However, c-ski mRNAs expressed in cells of the myogenic lineage are indistinguishable from c-ski transcripts in other cell types, raising the possibility that muscle-specific c-ski transcripts are expressed transiently. Avian cell lines QM7 and QM5 were used as a model to analyze changes in expression and alternative exon usage of c-ski during synchronous muscle differentiation. Upon serum deprivation, QM7 cells undergo myogenic differentiation. In contrast, QM5 cells cease proliferation but do not differentiate. Results show that levels of expression and alternative splicing of c-ski transcripts remain unchanged during cell cycle arrest or myogenic differentiation.
尽管ski原癌基因在细胞增殖、形态转化和成肌分化中发挥作用，但原癌基因c-ski的成肌活性尚未阐明。c-ski在胚胎发育过程中的成肌细胞内表达。在成肌起始早期的体节以及终末分化的骨骼肌中均可检测到原癌基因的转录本。然而，在成肌谱系细胞中表达的c-ski mRNA与其他细胞类型中的c-ski转录本并无差异，这增加了肌肉特异性c-ski转录本瞬时表达的可能性。禽细胞系QM7和QM5被用作模型，以分析同步肌肉分化过程中c-ski的表达变化和外显子可变剪接情况。血清剥夺后，QM7细胞发生成肌分化。相反，QM5细胞停止增殖但不分化。结果表明，在细胞周期停滞或成肌分化过程中，c-ski转录本的表达水平和可变剪接保持不变。
