Baines J D, Roizman B
Marjorie B. Kovler Viral Oncology Laboratories, University of Chicago, Illinois 60637.
J Virol. 1992 Sep;66(9):5621-6. doi: 10.1128/JVI.66.9.5621-5626.1992.
The UL15 gene of herpes simplex virus 1 (HSV-1) is encoded by two or more exons in all herpesvirus genomes sequenced to date. The UL15 coding region is highly conserved, and the intron invariably encodes other genes transcribed antisense to the UL15 coding region. Previously we reported that we deleted the intron domain encoding UL16 but were unable to delete UL15 (J. D. Baines and B. Roizman, J. Virol. 65:938-944, 1991). Here we report that we replaced exon I of UL15 with an unspliced cDNA copy of UL15 in HSV-1 DNA and deleted 58% of the carboxyl-terminal sequences of the natural copy of exon II, including the polyadenylation signal. The yields of infectious virus obtained upon infection with viruses containing the cDNA copy of UL15 were similar to those of an isogenic virus with a wild-type UL15 gene. We therefore conclude that the separation of the two exons of UL15 by an intron encoding two genes is not essential for the replication of HSV, at least in cell culture.
1型单纯疱疹病毒（HSV-1）的UL15基因在迄今测序的所有疱疹病毒基因组中由两个或更多个外显子编码。UL15编码区高度保守，内含子总是编码与UL15编码区反义转录的其他基因。先前我们报道过，我们删除了编码UL16的内含子结构域，但无法删除UL15（J.D.贝恩斯和B.罗伊兹曼，《病毒学杂志》65:938 - 944，1991年）。在此我们报道，我们用HSV-1 DNA中未剪接的UL15 cDNA拷贝替换了UL15的外显子I，并删除了外显子II天然拷贝58%的羧基末端序列，包括多聚腺苷酸化信号。用含有UL15 cDNA拷贝的病毒感染后获得的感染性病毒产量与具有野生型UL15基因的同基因病毒相似。因此我们得出结论，至少在细胞培养中，由编码两个基因的内含子将UL15的两个外显子分开对于HSV的复制不是必需的。
