Riley M I, Yoo W, Mda N Y, Folk W R
Department of Biochemistry, University of Missouri-Columbia, 65121, USA.
J Virol. 1997 Aug;71(8):6068-74. doi: 10.1128/JVI.71.8.6068-6074.1997.
Three mRNAs from the murine polyomavirus early region encode the three well-characterized tumor antigens. We report the existence of a fourth alternatively spliced mRNA which encodes a fourth tumor antigen, tiny T antigen, which comprises the amino-terminal domain common to all of the T antigens but is extended by six unique amino acid residues. The amount of tiny T antigen in infected cells is small because of its short half-life. Tiny T antigen stimulates the ATPase activity of Hsc70, most likely because of its DnaJ-like motif. The common amino-terminal domain may interface with chaperone complexes to assist the T antigens in carrying out their diverse functions of replication, transcription, and transformation in the appropriate cellular compartments.
来自鼠多瘤病毒早期区域的三种信使核糖核酸（mRNA）编码三种特征明确的肿瘤抗原。我们报告存在第四种可变剪接的mRNA，它编码第四种肿瘤抗原——微小T抗原，该抗原包含所有T抗原共有的氨基末端结构域，但延伸了六个独特的氨基酸残基。由于其半衰期短，感染细胞中微小T抗原的量很少。微小T抗原刺激热休克蛋白70（Hsc70）的ATP酶活性，很可能是因为其类似DnaJ的基序。共同的氨基末端结构域可能与伴侣蛋白复合物相互作用，以协助T抗原在适当的细胞区室中发挥其复制、转录和转化的多种功能。
