title: Characterization of papillomavirus E1 helicase mutants defective for interaction with the SUMO-conjugating enzyme Ubc9.
abstract: The E1 helicase from BPV and HPV16 interacts with Ubc9 to facilitate viral genome replication. We report that HPV11 E1 also interacts with Ubc9 in vitro and in the yeast two-hybrid system. Residues in E1 involved in oligomerization (353-435) were sufficient for binding to Ubc9 in vitro, but the origin-binding and ATPase domains were additionally required in yeast. Nuclear accumulation of BPV E1 was shown previously to depend on its interaction with Ubc9 and sumoylation on lysine 514. In contrast, HPV11 and HPV16 E1 mutants defective for Ubc9 binding remained nuclear even when the SUMO pathway was inhibited. Furthermore, we found that K514 in BPV E1 and the analogous K559 in HPV11 E1 are not essential for nuclear accumulation of E1. These results suggest that the interaction of E1 with Ubc9 is not essential for its nuclear accumulation but, rather, depends on its oligomerization and binding to DNA and ATP.
authors.affiliation: Laboratory of Molecular Virology, Institut de Recherches Cliniques de Montréal and Department of Biochemistry, University of Montreal, 110 Pine Avenue West, Montreal, Quebec, Canada H2W 1R7.
authors.forename: Amélie
authors.initials: A
authors.lastname: Fradet-Turcotte
authors.forename: Karine
authors.initials: K
authors.lastname: Brault
authors.forename: Steve
authors.initials: S
authors.lastname: Titolo
authors.forename: Peter M
authors.initials: PM
authors.lastname: Howley
authors.forename: Jacques
authors.initials: J
authors.lastname: Archambault
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology; D052140:Human papillomavirus 11 / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D030781:Organisms, Genetically Modified; D011487:Protein Conformation; D021381:Protein Transport / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism*; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: D004268:DNA-Binding Proteins; C084304:E1 protein, Human papillomavirus type 11; D025841:Small Ubiquitin-Related Modifier Proteins; D014764:Viral Proteins; D044763:Ubiquitin-Conjugating Enzymes; D000098843:Ubiquitin-Conjugating Enzyme UBC9