Cleavage of the cap binding protein complex polypeptide p220 is not effected by the second poliovirus protease 2A.
Cleavage of the cap binding protein complex polypeptide p220 is not effected by the second poliovirus protease 2A.
复制标题
帽结合蛋白复合物多肽p220的切割不受第二脊髓灰质炎病毒蛋白酶2A的影响。
DOI：
10.1016/0042-6822(86)90291-6
复制
发表时间：
1986
期刊：
影响因子：
3.7
通讯作者：
Ehrenfeld,E
中科院分区：
文献类型：
--
作者：
Lloyd,RE;Toyoda,H;Etchison,D;Wimmer,E;Ehrenfeld,E
脊髓灰质炎病毒蛋白2A含有一个短氨基酸序列，该序列也存在于已知病毒蛋白酶3C的推定活性位点，该蛋白酶3C先前显示负责脊髓灰质炎病毒多蛋白前体中的谷氨酰胺/甘氨酸裂解。实验证据表明，2A是第二种病毒蛋白酶，其介导两个酪氨酸/甘氨酸切割的切割，产生病毒特异性蛋白。由于脊髓灰质炎病毒对宿主细胞蛋白质合成的抑制与帽结合蛋白复合物的220，000-Da组分的特异性切割相关，我们已经测试了病毒蛋白2A是否含有p220切割活性。结果表明：（1）2A不具有p220切割活性，（2）部分纯化的含有高p220切割活性的组分中不含成熟蛋白或前体蛋白形式的2A序列，（3）抗2A血清或IgG在体外不抑制p220切割。
Poliovirus protein 2A contains a short amino acid sequence that also occurs in the putative active site of the known viral proteinase, 3C, previously shown to be responsible for glutamine/glycine cleavages in the poliovirus polyprotein precursor. Experimental evidence indicates that 2A is a second viral proteinase that mediates the cleavage of two tyrosine/glycine cleavages in the generation of virus-specific proteins. Since poliovirus inhibition of host cell protein synthesis correlates with the specific cleavage of the 220,000-Da component of the cap binding protein complex, we have tested whether viral protein 2A contains the p220 cleavage activity. The results show that (1) 2A does not copurify with p220 cleavage activity, (2) partially purified fractions containing high p220 cleavage activity contain no detectable 2A sequences in the form of either mature or precursor protein, and (3) anti-2A serum or IgG does not inhibit p220 cleavagein vitro.