GENE-MAPPING AND SEQUENCE-ANALYSIS OF THE UNIQUE SHORT REGION OF THE SIMIAN HERPESVIRUS SA-8 GENOME

A 10. 5 kbp Bam HI restriction fragment representing most of the uniqu e short (Us) region of the genome of the simian alpha-herpesvirus SA 8 was identified and cloned. Partial sequencing of this DNA fragment id entified regions of sequence homology with eight open reading frames ( ORFs) of HSV 1 and/or HSV 2. Sequence and size analysis of subcloned f ragments of the SA 8 Us region and comparison with homologous HSV Us s equences determined that the number, order, size, and orientation of S A 8 Us ORFs are comparable to those of HSV. Based on the location of t ranscriptional control elements, transcription of SA 8 Us genes appear s to be organized into 3' co-terminal mRNA sets as in HSV, although th e grouping of the gene sets is different. The SA 8 US 4 (gG) ORF is mo re similar to that of HSV 2 than HSV 1, both in size and predicted ami no acid sequence. Complete sequences were determined for five SA 8 gen es which represent homologs of the HSV gD, gE, gI, US 5, and US 9 gene s. The predicted polypeptides encoded by SA 8 are similar to the corre sponding HSV polypeptides. All SA 8 Us genes were more closely related to those of HSV than to related gene homologs of other mammalian alph a-herpesviruses.