Cleavage of four avian sarcoma virus polyproteins with virion protease p15 removes gag sequences and yields large fragments that function as tyrosine phosphoacceptors in vitro.
Cleavage of four avian sarcoma virus polyproteins with virion protease p15 removes gag sequences and yields large fragments that function as tyrosine phosphoacceptors in vitro.
复制标题
用病毒体蛋白酶 p15 裂解四种禽肉瘤病毒多蛋白，去除 gag 序列并产生在体外充当酪氨酸磷酸受体的大片段。
DOI：
10.1073/pnas.78.9.5847
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发表时间：
1981
影响因子：
11.1
通讯作者：
Vogt,PK
中科院分区：
文献类型：
--
作者：
Ghysdael,J;Neil,JC;Vogt,PK
禽肉瘤病毒PRCII、PRCII-p、Fujinami肉瘤病毒（FSV）和Esh肉瘤病毒（ESV）的转化特异性多聚蛋白由两个结构域组成，一个结构域来自部分病毒gag基因，另一个结构域代表缺陷病毒基因组中的明显细胞来源的插入物。用逆转录病毒蛋白酶p15切割这些gag连接的蛋白质。PRCII-p多聚蛋白P170、PRCII的P105和FSV的P140的切割发生在gag结构域内，并分别产生Mr为130，000、70，000和115，000的片段，其含有与原始gag序列的残余物连接的所有转化特异性序列。ESV P80在转化特异性结构域内被切割，从分子的NH 2-末端的一半产生Mr 35，000 - 38，000的片段，其由整个gag部分和一些非gag序列组成，并且产生Mr 48，000的片段，其含有大部分转化特异性序列。在每种情况下，在转化特异性片段中发现多蛋白的酪氨酸磷酸化位点。发现ESV P80的主要丝氨酸磷酸化位点位于Mr 35，000 - 38，000 gag的片段中，可能在该切割产物的转化特异性序列内。去除ESV P80的所有gag结构域或PRCII-p P170、PRCII P105和FSV P140中的大部分gag结构域不影响它们被多聚蛋白相关酪氨酸特异性蛋白激酶活性磷酸化的能力。这一观察结果表明，II类（PRCII-p，PRCII和FSV）和III类（ESV）禽肉瘤病毒的多蛋白的gag序列可能不需要这种酶功能，这似乎是重要的转化。
The transformation-specific polyproteins of avian sarcoma viruses PRCII, PRCII-p, Fujinami sarcoma virus (FSV), and Esh sarcoma virus (ESV) consist of two domains, one derived from a partial viral gag gene and the other representing an apparently cell-derived insert in the defective viral genome. These gag-linked proteins were cleaved with retrovirion protease p15. Cleavage of PRCII-p polyprotein P170, P105 of PRCII, and P140 of FSV occurred within the gag domain and generated fragments of Mr 130,000, 70,000, and 115,000, respectively, containing all of the transformation-specific sequences linked to a remnant of the original gag sequences. ESV P80 was cleaved inside the transformation-specific domain, yielding a Mr 35,000--38,000 fragment from the NH2-terminal half of the molecule consisting of the entire gag portion and some no-gag sequences and a Mr 48,000 fragment containing most of the transformation-specific sequences. The tyrosine phosphorylation sites of the polyproteins were found in every case in the transformation-specific fragments. The major serine phosphorylation site of ESV P80 was found to reside in the Mr 35,000--38,000 gag-containing fragment, probably within the transformation-specific sequences of that cleavage product. Removal of all of the gag domain of ESV P80 or most of the gag domain in PRCII-p P170, PRCII P105, and FSV P140 does not affect their ability to be phosphorylated by the polyprotein-associated tyrosine-specific protein kinase activities. This observation suggests that the gag sequences of the polyproteins of classes II (PRCII-p, PRCII, and FSV) and III (ESV) avian sarcoma viruses may not be required for this enzymatic function, which appears to be of importance in transformation.