Stephenson J R, Khan A S, Sliski A H, Essex M
Proc Natl Acad Sci U S A. 1977 Dec;74(12):5608-12. doi: 10.1073/pnas.74.12.5608.
The feline oncornavirus-associated cell membrane antigen (FOCMA) acts as a target for natural immuno-surveillance against tumor development in the cat. In the present study, mink and rat cells nonproductively transformed by feline sarcoma virus (FeSV) were shown to express FOCMA as well as 5'-terminal feline leukemia virus (FeLV) gag gene proteins, p15 and p12. In contrast, such cells lack detectable levels of other FeLV gag gene-coded proteins or the env gene product, gp70. FOCMA, p15, and p12 antigen expression is initially in the form of an 80,000-100,000 molecular weight precursor which, upon post-translational cleavage, gives rise to a 65,000 molecular weight component that contains FOCMA and a 25,000 molecular weight component containing p15 and p12. Feline lymphoma cells, including those from several tumors that lacked detectable levels of FeLV structural protein expression, were shown to be FOCMA-positive. These findings strongly suggest that FOCMA represents an FeSV-coded transformation specific protein and provide preliminary information regarding the position within the FeSV genome coding for its synthesis.
猫肿瘤病毒相关细胞膜抗原（FOCMA）是猫体内针对肿瘤发生的天然免疫监视的靶点。在本研究中，猫肉瘤病毒（FeSV）非生产性转化的貂和大鼠细胞显示出表达FOCMA以及5'-末端猫白血病病毒（FeLV）gag基因蛋白p15和p12。相比之下，此类细胞缺乏可检测水平的其他FeLV gag基因编码蛋白或env基因产物gp70。FOCMA、p15和p12抗原最初以80,000 - 100,000分子量的前体形式表达，经翻译后切割，产生一个包含FOCMA的65,000分子量组分和一个包含p15和p12的25,000分子量组分。猫淋巴瘤细胞，包括来自几个缺乏可检测水平FeLV结构蛋白表达的肿瘤的细胞，被证明为FOCMA阳性。这些发现强烈表明FOCMA代表一种FeSV编码的转化特异性蛋白，并提供了关于FeSV基因组中编码其合成的位置的初步信息。
