The bovine papillomavirus type 1 E2 transactivator and repressor proteins use different nuclear localization signals
The bovine papillomavirus type 1 E2 transactivator and repressor proteins use different nuclear localization signals
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DOI：
10.1128/jvi.70.2.1117-1124.1996
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发表时间：
1996-02-01
影响因子：
5.4
通讯作者：
McBride, AA
中科院分区：
文献类型：
--
作者：
Skiadopoulos, MH;McBride, AA
牛乳头瘤病毒1型E2基因编码至少3种调节病毒转录和DNA复制的核磷酸化蛋白，这3种蛋白都有一个共同的c端结构域，具有DNA结合和二聚化活性。该结构域的一个基区形成一个与DNA靶标直接接触的α螺旋，本研究表明，该基区除了在DNA结合中起作用外，还在E2 DNA结合域和异源蛋白中起核定位信号的作用，该信号序列的缺失导致细胞质中E2反激活子和抑制蛋白的积累增加，但核定位并未消除。在全长反活化蛋白中，存在于n端反活化结构域的另一个信号被用于转运到细胞核，而c端核定位信号被掩盖。使用不同的核定位信号可能允许在病毒生命周期的某个阶段对E2反激活子和抑制蛋白的亚细胞定位进行差异调节。
The E2 gene of bovine papillomavirus type 1 encodes at least three nuclear phosphoproteins that regulate viral transcription and DNA replication, All three proteins have a common C-terminal domain that has DNA-binding and dimerization activities. A basic region in this domain forms an alpha helix which makes direct contact with the DNA target, In this study, it is shown that in addition to its role in DNA binding, this basic region functions as a nuclear localization signal both in the E2 DNA-binding domain and in a heterologous protein, Deletion of this signal sequence resulted in increased accumulation of the E2 transactivator and repressor proteins in the cytoplasm, but nuclear localization was not eliminated, In the full-length transactivator protein, another signal, present in the N-terminal transactivation domain, is used for transport to the nucleus, and the C-terminal nuclear localization signal(s) are masked. The use of different nuclear localization signals could potentially allow differential regulation of the subcellular localization of the E2 transactivator and repressor proteins at some stage in the viral life cycle.