title: Genetic analysis of the E2 transactivation domain dimerization interface from bovine papillomavirus type 1.
abstract: The bovine papillomavirus type 1 (BPV1) E2 protein binds as a dimer to the viral genome to promote its transcription, replication and maintenance in keratinocytes. Although BPV1 E2 dimerizes primarily through its DNA-binding domain, it was shown previously that its transactivation domain (TAD) can also dimerize in vitro through formation of a disulfide bond between cysteine 57 (C57) of adjacent monomers and of an ion pair between arginine 172 (R172) and aspartic acid 175 (D175). The function of this TAD dimerization interface in vivo remains unknown. Here, we report the effects of substituting C57, R172 and D175 by alanine on the transactivation activity of BPV E2 as well as on its ability to support viral DNA replication using a novel luciferase-based assay. Results for this mutational analysis suggest that the TAD dimerization interface is not essential for either process but may contribute to the DNA replication activity of BPV1 E2.
authors.affiliation: Molecular Virology Laboratory, Institut de Recherches Cliniques de Montréal (IRCM) and Department of Biochemistry, Université de Montréal, Montreal, QC, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Gagnon
authors.forename: Hélène
authors.initials: H
authors.lastname: Sénéchal
authors.forename: Claudia M
authors.initials: CM
authors.lastname: D'Abramo
authors.forename: Jennifer
authors.initials: J
authors.lastname: Alvarez
authors.forename: Alison A
authors.initials: AA
authors.lastname: McBride
authors.forename: Jacques
authors.initials: J
authors.lastname: Archambault
mesh_terms: D019943:Amino Acid Substitution; D052688:Bovine papillomavirus 1 / Q000235:genetics / Q000502:physiology*; D004252:DNA Mutational Analysis; D004279:DNA, Viral / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D055503:Protein Multimerization; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D004268:DNA-Binding Proteins; C051550:E2 protein, Bovine papillomavirus; D050505:Mutant Proteins; D014764:Viral Proteins