Precursor of human adenovirus core polypeptide Mu targets the nucleolus and modulates the expression of E2 proteins.
We have examined the subcellular localization properties of human adenovirus 2 (HAdV-2) preMu and mature Mu (pX) proteins as fusions with enhanced green fluorescence protein (EGFP). We determined that preMu is exclusively a nucleolar protein with a single nucleolar accumulation signal within the Mu sequence. In addition, we noted that both preMu-EGFP and Mu-EGFP are excluded from adenovirus DNA-binding protein (DBP)-rich replication centres in adenovirus-infected cells. Surprisingly, we observed that cells in which preMu-EGFP (but not Mu-EGFP) is transiently expressed prior to or shortly after infection with Ad2 did not express late adenovirus genes. Further investigation suggested this might be due to a failure to express pre-terminal protein (preTP) from the E2 region, despite expression of another E2 protein, DBP. Deletion mutagenesis identified a highly conserved region in the C terminus of preMu responsible for these observations. Thus our data suggest that preMu may play a role in modulating accumulation of proteins from the E2 region.
Lee
T W R
TWR
School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
Lawrence
F J
FJ
Division of Virology, Department of Pathology and Microbiology, University Walk, Bristol University, Bristol BS8 1TD, UK.
Dauksaite
V
V
Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, S-75123 Uppsala, Sweden.
Akusjärvi
G
G
Department of Medical Biochemistry and Microbiology, Uppsala University, Box 582, S-75123 Uppsala, Sweden.
Blair
G E
GE
School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
Matthews
D A
DA
Division of Virology, Department of Pathology and Microbiology, University Walk, Bristol University, Bristol BS8 1TD, UK.
D017502:Adenovirus E2 Proteins / Q000378:metabolism*; D000260:Adenoviruses, Human / Q000472:pathogenicity; D000595:Amino Acid Sequence; D002466:Cell Nucleolus / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D017353:Gene Deletion; D015967:Gene Expression Regulation, Viral; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism*; D011498:Protein Precursors / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014758:Viral Core Proteins / Q000378:metabolism*
D017502:Adenovirus E2 Proteins; D004268:DNA-Binding Proteins; D008164:Luminescent Proteins; D010455:Peptides; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; D014758:Viral Core Proteins; C061289:virion protein mu, adenovirus; D049452:Green Fluorescent Proteins