Identification of a 1.6 kb genome locus of guinea pig cytomegalovirus required for efficient viral growth in animals but not in cell culture.
Guinea pig cytomegalovirus (GPCMV) provides a useful model for studies of congenital CMV infection. During characterization of the GPCMV genome sequence, we identified two types of strains in a virus stock purchased from ATCC. One of them, GPCMV/del, lacks a 1.6 kb locus that positionally corresponds to murine CMV (MCMV) M129-M133. Growth of GPCMV/del in cell culture was marginally better than that of the other strain, GPCMV/full, which harbors the 1.6 kb locus. However, in animals infected intraperitoneally with virus stocks containing both strains, GPCMV/full disseminated more efficiently than GPCMV/del, including 200-fold greater viral load in salivary glands. Viral DNA, transcripts of the immediate-early 2 gene homolog, and viral antigens were more abundant in animals infected with GPCMV/full than in those infected with GPCMV/del. Although the observed phenomena have some similarity with the growth properties of MCMV strains defective in mck-1/mck-2(M129/131) and those defective in sgg(M132), no M129-M132 homologs were found in the 1.6 kb locus. Since one of the ORFs in the locus has a weak sequence similarity with HCMV UL130, which relates to cell tropism, further studies will be required to learn the mechanism for efficient GPCMV growth in animal.
Nozawa
Naoki
N
Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
Yamamoto
Yumiko
Y
Fukui
Yoshiko
Y
Katano
Harutaka
H
Tsutsui
Yoshihiro
Y
Sato
Yuko
Y
Yamada
Souichi
S
Inami
Yuhki
Y
Nakamura
Kohnosuke
K
Yokoi
Masayuki
M
Kurane
Ichiro
I
Inoue
Naoki
N
D000818:Animals; D000956:Antigens, Viral / Q000096:biosynthesis; D018929:Cell Culture Techniques; D002460:Cell Line; D004279:DNA, Viral / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D016679:Genome, Viral; D006168:Guinea Pigs; D008099:Liver / Q000473:pathology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000096:biosynthesis; D019211:Roseolovirus / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity*; D019349:Roseolovirus Infections / Q000821:virology; D012469:Salivary Glands / Q000821:virology; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D017385:Sequence Homology; D013154:Spleen / Q000473:pathology; D010948:Viral Plaque Assay; D014779:Virus Replication
D000956:Antigens, Viral; D004279:DNA, Viral; D012367:RNA, Viral