FUNCTIONS OF THE SIMIAN VIRUS 40 SMALL-T ANTIGEN

本研究的总体目标是确定 SV40小T抗原及其与之结合的两种细胞蛋白 合伙人。主要的工作将放在新陈代谢的研究上 表达小T抗原的细胞的模式，因为最近的研究已经 表明抗线粒体药物和离子载体改变了生长模式 在CV-1细胞中观察到与小T抗原的存在有关。 质膜功能，如转运和膜电位，将 也可检测与小T抗原有关的抗原。 我们还将继续观察到其中一种细胞蛋白32K， 似乎与S-腺苷蛋氨酸(SAM)结合。这引发了 32K蛋白可能是一种利用SAM作为一种 底物，并可能提供关于至少一个功能的主要线索 一种细胞蛋白，间接地，小T细胞的功能 抗原。 小T抗原和细胞蛋白的纯化将是 继续和扩大，特别强调净化 细菌克隆表达的可溶性Small-t抗原。隔离 保留与细胞相互作用能力的小T抗原 蛋白质是优先考虑的。 其他努力包括开发杂交瘤细胞系，以产生 识别小T抗原细胞蛋白复合体的抗体 高效，或识别小T抗原的独特区域。如果 后者是获得的，试图鉴定和活性的蛋白质片段 从小T抗原会在感染细胞中制造出来。的势函数 也可以使用细菌克隆来接近这样的片段 只包含来自小T抗原这个区域的DNA序列，以及来自 哪些小t的独特序列可以在细菌中表达。

The overall aim of this research is the determination of the functions of SV40 small-t antigen and of two cellular proteins with which it associates. Major effort will be placed on investigations of the metabolic patterns of cells that express small-t antigen, because recent studies have shown that antimitochondrial drugs and ionophores modify growth patterns observed in CV-1 cells which relate to the presence of small-t antigen. Plasma membrane functions, such as transport and membrane potential, will also be examined and related to small-t antigen. We will also pursue the observation that one of the cellular proteins, 32K, appears to be binding S-adenosylmethionine (SAM). This raises the possibility that the 32K protein may be an enzyme which uses SAM as a substrate, and may provide a major clue concerning the function of at least one of the cellular proteins and, indirectly, the function of small-t antigen. Purifications of small-t antigen and the cellular proteins will be continued and scaled-up, with particular emphasis on purification of the soluble small-t antigen expressed by a bacterial clone. Isolation of small-t antigen which retains the ability to interact with the cellular proteins is a priority. Additional efforts include development of hybridoma cell lines that produce antibodies that recognize the small-t antigen cellular protein complex efficiently, or that recognize the unique region of small-t antigen. If the latter is obtained, attempts to identify and active protein fragment from small-t antigen in infected cells will be made. Potential function of such a fragment is also being approached using a bacterial clone that contains DNA sequences only from this region of small-t antigen, and from which small-t unique sequences can be expressed in bacteria.