title: Effects of single amino acid substitutions at the predicted coiled-coil or hydrophobic region on the self-assembly of phi29 replication protein, gp1.
abstract: Gp1, the product of one of the essential genes of phi29 replication, is an RNA binding protein and self-associates to form large complexes. Furthermore, gp1 suppresses the synthesis of phi29 DNA polymerase and primer protein in the post-transcriptional process. In this report, we have employed seven variants with single amino acid substitutions to analyze the self-assembly of gp1. Using chemical cross-linking and sedimentation assays, amino acid substitutions within the predicted coiled-coil or hydrophobic region were shown to strongly affect the formation of large complexes, suggesting that these two regions were required for the self-assembly of gp1. The self-association of gp1 was suggested to be necessary for the efficient binding to RNA and the translational repression.
authors.affiliation: Department of Genetics, Life Science Institute, Sophia University, 7-1 Kioi-cho Chiyoda-Ku, Tokyo 102-8554, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Hashiyama
authors.forename: Ari
authors.initials: A
authors.lastname: Takeuchi
authors.forename: Osamu
authors.initials: O
authors.lastname: Makino
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D036022:Capsid Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D017433:Protein Structure, Secondary; D012313:RNA / Q000378:metabolism
chemical_list: D036022:Capsid Proteins; C079841:portal protein, bacteriophage P22; D012313:RNA