The essential protein encoded by the UL31 gene of herpes simplex virus 1 depends for its stability on the presence of UL34 protein.
The essential protein encoded by the UL31 gene of herpes simplex virus 1 depends for its stability on the presence of UL34 protein.
复制标题
DOI：
10.1073/pnas.97.20.11002
复制
发表时间：
2000-09
影响因子：
11.1
通讯作者：
G. Ye;B. Roizman
中科院分区：
文献类型：
--
作者：
G. Ye;B. Roizman
为了进一步研究由U（L）34基因编码的蛋白质与动力蛋白的中间链结合的早期观察结果，我们构建了一系列突变体，从这些突变体中缺失编码整个蛋白质（Δ U（L）34）或氨基末端[U（L）34 Δ（3-119）]或羧基末端[U（L）34 Δ（245-275）]结构域的序列。缺乏编码羧基末端结构域的序列的突变体在所有测试的细胞系中生长。另外两个突变体仅以细胞类型依赖的方式复制，并且很差。用不包含U（L）31 ORF的片段拯救DeltaU（L）34突变体恢复野生型表型。U（L）34蛋白与U（L）31蛋白发生物理相互作用，U（L）31缺失突变体表现出与U（L）34缺失突变体相似的表型。设计用于确定缺失突变体的表型是否具有共同碱基的实验显示，感染DeltaU（L）34突变体的细胞积累U（L）31 RNA，但不积累相应的蛋白质。然而，在用DeltaU（L）34突变体感染并在感染后6小时用MG 132蛋白体抑制剂处理的细胞中，U（L）31蛋白积累至接近野生型病毒感染的细胞水平。这证明了一种重要病毒蛋白的稳定性需要另一种蛋白的存在。这一观察结果提高了根据对基因缺失或缺失的突变体的表型分析来鉴定基因功能的标准。
To pursue an earlier observation that the protein encoded by the U(L)34 gene binds to intermediate chain of dynein, we constructed a series of mutants from which sequences encoding the entire protein (DeltaU(L)34) or amino-terminal [U(L)34Delta(3-119)] or carboxyl-terminal [U(L)34Delta(245-275)] domains were deleted. The mutant lacking the sequence encoding the carboxyl-terminal domain grew in all cell lines tested. The two other mutants replicated only in cell type-dependent manner and poorly. Rescue of DeltaU(L)34 mutant with a fragment that does not encompass the U(L)31 ORF restored wild-type phenotype. U(L)34 protein interacts physically with U(L)31, and the U(L)31 deletion mutant appears to have a phenotype similar to that of U(L)34 deletion mutant. Experiments designed to determine whether the phenotypes of the deletion mutants have a common base revealed that cells infected with the DeltaU(L)34 mutant accumulate U(L)31 RNA but not the corresponding protein. The U(L)31 protein accumulated, however, to near wild-type virus-infected cell levels in cells infected with DeltaU(L)34 mutant and treated with the MG132 proteosomal inhibitor at 6 h after infection. This is evidence that the stability of an essential viral protein requires the presence of another protein. The observation raises the bar for identification of gene function on the basis of analyses of the phenotype of mutants in which the gene has been deleted or rendered inoperative.