Moffat J F, Zerboni L, Sommer M H, Heineman T C, Cohen J I, Kaneshima H, Arvin A M
Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305, USA.
Proc Natl Acad Sci U S A. 1998 Sep 29;95(20):11969-74. doi: 10.1073/pnas.95.20.11969.
The varicella-zoster virus (VZV) genes ORF47 and ORF66 are predicted to encode serine/threonine protein kinases, which are homologs of herpes simplex virus 1 (HSV-1) UL13, and US3. When mutants were constructed by inserting stop codons into ORF47 and ORF66, the recombinants ROka47S and ROka66S, as well as intact ROka replicated in tissue culture. In contrast, inoculation of human thymus/liver or skin implants in SCID-hu mice showed that ORF47 protein was required for viral growth in human T cells and skin. Eliminating ORF66 expression inhibited VZV infectivity for T cells partially but did not impair replication in skin compared with ROka. Infectivity for T cells and skin was restored when ROka47S virus was complemented by insertion of ORF47 into a distant, noncoding site. The ORF47 gene product is the first VZV protein identified as necessary for T cell tropism. It also is essential for skin infectivity in vivo, as is glycoprotein C. Expression of ORF66 did not compensate for the absence of the ORF47 protein. The requirement for ORF47 expression in T cells and skin indicates that this gene product, which is dispensable in vitro, has a critical role within differentiated cells that are essential targets for VZV pathogenesis in vivo.
水痘带状疱疹病毒（VZV）的ORF47和ORF66基因预计编码丝氨酸/苏氨酸蛋白激酶，它们是单纯疱疹病毒1型（HSV-1）UL13和US3的同源物。当通过在ORF47和ORF66中插入终止密码子构建突变体时，重组体ROka47S和ROka66S以及完整的ROka在组织培养中均可复制。相比之下，将人胸腺/肝脏或皮肤植入物接种到SCID-hu小鼠体内显示，ORF47蛋白是病毒在人T细胞和皮肤中生长所必需的。与ROka相比，消除ORF66表达可部分抑制VZV对T细胞的感染性，但不损害其在皮肤中的复制。当将ORF47插入到一个较远的非编码位点对ROka47S病毒进行互补时，其对T细胞和皮肤的感染性得以恢复。ORF47基因产物是首个被确定为T细胞嗜性所必需的VZV蛋白。它对于体内皮肤感染性也至关重要，糖蛋白C亦是如此。ORF66的表达并不能弥补ORF47蛋白的缺失。在T细胞和皮肤中对ORF47表达的需求表明，这种在体外可有可无的基因产物，在分化细胞中具有关键作用，而这些分化细胞是VZV体内致病的重要靶标。
