Kopchick J J, Karshin W L, Arlinghaus R B
J Virol. 1979 May;30(2):610-23. doi: 10.1128/JVI.30.2.610-623.1979.
[3H]tyrosine-labeled viral precursor polyproteins and known mature viral proteins derived from the Rauscher murine leukemia virus gag and pol genes were examined by two-dimensional tryptic peptide mapping. Pr200gag-pol was found to contain peptide sequences of the viral core proteins p30, p15, p12, and p10, as well as peptide sequences found in the cell-associated reverse transcriptase. Intermediate reverse transcriptase precursor Pr125pol lacked peptide sequences of the four-core proteins but contained reverse transcriptase-specific tryptic peptides plus two additional tyrosine-containing tryptic peptides not related to gag or pol gene products. Methionine-containing tryptic peptide analysis also suggested the presence of additional protein material in Pr125pol (Kopchick et al., Proc. Natl. Acad. Sci. U.S.A. 75:2016-2020, 1978). Pr200gag-pol, although containing both viral core and reverse transcriptase-assoicated methionine and tyrosine tryptic peptides, also contained additional tryptic peptides. Thes are of two classes: (i) tryptic peptides associated with the Pr125pol but not Pr80pol and (ii) tryptic peptides not found in Pr125pol or in any known viral protein. One interpretation of these results is that Pr200gag-pol contains additional gene products aside from the gag and pol genes. Pr80gag and Pr65gag peptide maps were also examined and found to have sequences of all four core proteins. Pr65gag was found to contain two p30 tyrosine tryptic peptides that were absent in Pr80gag, suggesting that Pr80gag may not be the precursor to Pr65gag. Pr80gag, as expected from its larger size, also contained tryptic peptides not found in Pr65gag. Two of these additional Pr80gag tryptic peptides were found in Pr80pol as well but not in any of the viral core proteins, suggesting that Pr80gag and Pr80pol may have overlapping peptide sequences. Consistent with this finding is the conclusion that Pr80gag terminates within the pol gene. A model that describes the relationship of these recent findings to viral gene products is presented.
通过二维胰蛋白酶肽图谱分析，对源自劳斯氏鼠白血病病毒gag和pol基因的[3H]酪氨酸标记的病毒前体多蛋白及已知的成熟病毒蛋白进行了检测。发现Pr200gag-pol含有病毒核心蛋白p30、p15、p12和p10的肽序列，以及细胞相关逆转录酶中发现的肽序列。中间逆转录酶前体Pr125pol缺乏四种核心蛋白的肽序列，但含有逆转录酶特异性胰蛋白酶肽以及另外两个与gag或pol基因产物无关的含酪氨酸的胰蛋白酶肽。含甲硫氨酸的胰蛋白酶肽分析也表明Pr125pol中存在额外的蛋白质物质（科普奇克等人，《美国国家科学院院刊》75:2016 - 2020，1978）。Pr200gag-pol虽然同时含有病毒核心以及与逆转录酶相关的甲硫氨酸和酪氨酸胰蛋白酶肽，但也含有额外的胰蛋白酶肽。这些肽分为两类：（i）与Pr125pol相关但与Pr80pol无关的胰蛋白酶肽，以及（ii）在Pr125pol或任何已知病毒蛋白中未发现的胰蛋白酶肽。对这些结果的一种解释是，Pr200gag-pol除了gag和pol基因外还含有额外的基因产物。还对Pr80gag和Pr65gag的肽图谱进行了检测，发现它们具有所有四种核心蛋白的序列。发现Pr65gag含有两个Pr80gag中不存在的p30酪氨酸胰蛋白酶肽，这表明Pr80gag可能不是Pr65gag的前体。正如预期的那样，Pr80gag因其较大的尺寸，还含有Pr65gag中未发现的胰蛋白酶肽。这些额外的Pr80gag胰蛋白酶肽中的两个在Pr80pol中也有，但在任何病毒核心蛋白中都没有，这表明Pr80gag和Pr80pol可能具有重叠的肽序列。与此发现一致的结论是，Pr80gag在pol基因内终止。本文提出了一个描述这些最新发现与病毒基因产物关系的模型。
