A domain of SV40 capsid polypeptide VP1 that specifies migration into the cell nucleus.
A domain of SV40 capsid polypeptide VP1 that specifies migration into the cell nucleus.
复制标题
SV40 衣壳多肽 VP1 的一个结构域，指定迁移到细胞核中。
作者：
C. Wychowski;D. Bénichou;M. Girard
为了鉴定负责猴病毒40（SV 40）多肽VP 1核迁移的决定簇，将SV 40 VP 1基因的5′-末端部分与脊髓灰质炎病毒衣壳多肽VP 1的完整cDNA序列融合，并将杂合基因插入SV 40载体中代替正常SV 40 VP 1基因。在杂交基因的SV 40 VP 1部分中产生了不同长度的缺失，导致一组截短的基因编码SV 40 VP 1的2 - 40个NH 2-末端氨基酸，然后是脊髓灰质炎病毒VP 1。在存在早期SV 40琥珀突变体作为辅助病毒的情况下，用缺失的杂交病毒感染猴肾细胞，并使用抗脊髓灰质炎病毒VP 1免疫血清通过间接免疫荧光测定融合蛋白的亚细胞定位。发现来自SV 40 VP 1的前11个NH 2末端氨基酸的存在足以使融合蛋白靶向细胞核。接着产生从蛋白质的NH 2-向COOH-末端延伸的缺失。当SV 40 VP 1的前8个氨基酸缺失时，SV 40 VP 1-脊髓灰质炎病毒VP 1融合多肽向细胞核的转运被消除。因此，SV 40 VP 1的前8个NH 2-末端氨基酸序列似乎含有足以将蛋白质靶向细胞核的核迁移信号。
In order to identify the determinants responsible for the nuclear migration of simian virus 40 (SV40) polypeptide VP1, the 5′‐terminal portion of the SV40 VP1 gene was fused with the complete cDNA sequence of poliovirus capsid polypeptide VP1 and the hybrid gene was inserted into an SV40 vector in place of the normal SV40 VP1 gene. Deletions of various length were generated in the SV40 VP1 portion of the hybrid gene, resulting in a set of truncated genes encoding 2‐40 NH2‐terminal amino acids from SV40 VP1, followed by poliovirus VP1. Monkey kidney cells were infected by the deleted hybrid viruses in the presence of an early SV40 amber mutant as helper, and the subcellular localization of the fusion proteins was determined by indirect immunofluorescence using an anti‐poliovirus VP1 immune serum. The presence of the first 11 NH2‐terminal amino acids from SV40 VP1 was found to be sufficient to target the fusion protein to the cell nucleus. Deletions extending from the NH2‐ towards the COOH‐terminal end of the protein were next generated. Transport of the SV40 VP1‐poliovirus VP1 fusion polypeptide to the nucleus was abolished when the first eight amino acids from SV40 VP1 were deleted. Thus the sequence of the first eight NH2‐terminal amino acids of SV40 VP1 appears to contain a nuclear migration signal which is sufficient to target the protein to the cell nucleus.