Identification, analysis, and evolutionary relationships of the putative murine cytomegalovirus homologs of the human cytomegalovirus UL82 (pp71) and UL83 (pp65) matrix phosphoproteins.
We have identified three open reading frames (ORFs) in murine cytomegalovirus (MCMV), designated M82, M83, and M84, which likely encode homologs of the human cytomegalovirus (HCMV) UL82 and UL83 matrix phosphoproteins. These ORFs, in the HindIII C fragment of MCMV, are colinear with the UL82, UL83, and UL84 ORFs of HCMV. M82 encodes a 598-amino-acid (aa) protein with homology to UL82, M83 encodes an 809-aa protein with homology to UL82 and UL83, and M84 encodes a 587-aa protein with homology to UL83 and UL84. Analysis of transcription by Northern (RNA) blotting indicated that the M82 and M83 ORFs are transcribed as 2.2- and 5-kb mRNAs, respectively, at 24 to 48 h postinfection (p.i.), while M84 is transcribed as a 6.9-kb mRNA only at 8 h p.i. All transcripts appear to terminate at the same position 3' of the M82 ORF. Of the products of the three ORFs, only M83 is strongly recognized by hyperimmune mouse serum. The M83 protein is a virion-associated phosphoprotein with an apparent molecular mass of 125 kDa. In MCMV-infected cells, it is detectable by Western blotting (immunoblotting) only at 48 h p.i. in the absence of phosphonoacetic acid, consistent with late gene expression. The M83 ORF is also expressed at high levels in cells infected by a recombinant vaccinia virus and yields a protein which is serologically cross-reactive and comigrates with the authentic MCMV protein in sodium dodecyl sulfate-polyacrylamide gel electrophoresis.
Cranmer
L D
LD
Department of Biology, University of California, San Diego, La Jolla 92093-0357, USA.
Clark
C L
CL
Morello
C S
CS
Farrell
H E
HE
Rawlinson
W D
WD
Spector
D H
DH
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D001483:Base Sequence; D003587:Cytomegalovirus / Q000378:metabolism; D004279:DNA, Viral; D015247:Deoxyribonuclease HindIII / Q000378:metabolism; D019143:Evolution, Molecular; D005260:Female; D015870:Gene Expression; D005822:Genetic Vectors; D006566:Herpesviridae Infections / Q000276:immunology / Q000821:virology; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D018146:Muromegalovirus / Q000235:genetics* / Q000378:metabolism; D016366:Open Reading Frames; D010750:Phosphoproteins / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation; D010802:Phylogeny; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014616:Vaccinia virus / Q000235:genetics; D014763:Viral Matrix Proteins / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics; D014771:Virion / Q000378:metabolism
D004279:DNA, Viral; C102375:M82 protein, murine cytomegalovirus; C102374:M83 protein, murine cytomegalovirus; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D014763:Viral Matrix Proteins; D014764:Viral Proteins; C065418:cytomegalovirus matrix protein 65kDa; C051298:cytomegalovirus phosphoprotein 71kDa; C072218:UL84 protein, Cytomegalovirus; D015247:Deoxyribonuclease HindIII