The intranuclear location of simian virus 40 polypeptides VP2 and VP3 depends on a specific amino acid sequence
The intranuclear location of simian virus 40 polypeptides VP2 and VP3 depends on a specific amino acid sequence
复制标题
猿猴病毒40多肽VP2和VP3的核内定位取决于特定的氨基酸序列
作者：
C. Wychowski;D. Bénichou;M. Girard
将编码脊髓灰质炎病毒衣壳多肽VP1的基因片段插入猴病毒40(SV40)基因组中，取代SV40的VP1基因，并与VP2-VP3基因的3‘端进行同相融合。在早期SV40突变体作为助手的情况下，用所产生的杂交病毒感染猴细胞。用抗脊髓灰质炎病毒VP1免疫血清对感染细胞进行间接免疫荧光分析表明，SV40/脊髓灰质炎病毒融合蛋白位于细胞核内。利用BAL31核酸酶在杂交基因的SV40VP2-VP3部分产生了不同长度的缺失。由此产生的病毒基因组表达剪接的融合蛋白，其细胞内的位置要么在核内，要么在胞质内，这取决于VP2氨基酸残基317到323(Pro-ASN-Lys-Arg-Lys)的存在或不存在。通过320位的Lys残基的定点突变证实了这一点。将Lys-320修饰为苏氨酸或天冬氨酸，可消除融合蛋白的核聚集。结果表明，VP2的317~323位氨基酸序列中至少有一部分能使VP2和VP3稳定地定位于细胞核内。这些蛋白质很可能是通过相互作用从细胞质运输到细胞核的，VP1作为载体。
A cDNA fragment coding for poliovirus capsid polypeptide VP1 was inserted into a simian virus 40 (SV40) genome in the place of the SV40 VP1 gene and fused in phase to the 3' end of the VP2-VP3 genes. Simian cells were infected with the resulting hybrid virus in the presence of an early SV40 mutant used as a helper. Indirect immunofluorescence analysis of the infected cells using anti-poliovirus VP1 immune serum revealed that the SV40/poliovirus fusion protein was located inside the cell nucleus. Deletions of various lengths were generated in the SV40 VP2-VP3 portion of the hybrid gene using BAL31 nuclease. The resulting virus genomes expressed spliced fusion proteins whose intracellular location was either intranuclear or intracytoplasmic, depending on the presence or absence of VP2 amino acid residues 317 to 323 (Pro-Asn-Lys-Lys-Lys-Arg-Lys). This was confirmed by site-directed mutagenesis of the Lys residue at position 320. Modification of Lys-320 into either Thr or Asn abolished the nuclear accumulation of the fusion protein. It is concluded that at least part of the sequence of VP2 amino acids 317 to 323 allows VP2 and VP3 to remain stably located inside the cell nucleus. The proteins are most probably transported from the cell cytoplasm to the cell nucleus by interaction, with VP1 acting as a carrier.
DOI：
10.1073/pnas.81.19.5951
发表时间：
1984-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
SILVER, PA;KEEGAN, LP;PTASHNE, M
通讯作者：
PTASHNE, M