Adeno-associated virus interactions with B23/Nucleophosmin: identification of sub-nucleolar virion regions.
Adeno-associated virus (AAV) is a human parvovirus that normally requires a helper virus such as adenovirus (Ad) for replication. The four replication proteins (Rep78, 68, 52 and 40) encoded by AAV are pleiotropic effectors of virus integration, replication, transcription and virion assembly. Using Rep68 column chromatography and mass spectrometry, we have identified the nucleolar, B23/Nucleophosmin (NPM) protein as an Rep-interacting partner. Rep-NPM interactions were verified by co-immunofluorescence and chemical cross-linking studies. We have found that there is demonstrable, but limited co-localization between Rep and NPM in co-infected cells. In contrast, there was significant co-localization between NPM and AAV Cap proteins. In vitro experiments using purified MBPRep78 and NPM show that NPM stimulates MBPRep78 interactions with the AAV ITR as well as endonuclease activity. These studies suggest that NPM plays a role in AAV amplification affecting Rep function and virion assembly.
Bevington
Joyce M
JM
Department of Biochemistry and Cancer Biology, University of Toledo College of Medicine, 3035 Arlington Ave., Toledo, OH 43614-5804, USA.
Needham
Patrick G
PG
Verrill
Kristin C
KC
Collaco
Roy F
RF
Basrur
Venkatesh
V
Trempe
James P
JP
D002466:Cell Nucleolus / Q000378:metabolism* / Q000821:virology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D000229:Dependovirus / Q000302:isolation & purification / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D047468:Immunoprecipitation; D009687:Nuclear Proteins / Q000502:physiology*; D000090243:Nucleophosmin; D011485:Protein Binding; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D014771:Virion / Q000502:physiology*; D019065:Virus Assembly
D004268:DNA-Binding Proteins; C000716967:NPM1 protein, human; D009687:Nuclear Proteins; D014764:Viral Proteins; D000090243:Nucleophosmin; C068734:rep proteins, Adeno-associated virus 2