Adeno-associated virus site-specific integration is regulated by TRP-185.
Adeno-associated virus (AAV) integrates site specifically into the AAVS1 locus on human chromosome 19. Although recruitment of the AAV nonstructural protein Rep78/68 to the Rep binding site (RBS) on AAVS1 is thought to be an essential step, the mechanism of the site-specific integration, particularly, how the site of integration is determined, remains largely unknown. Here we describe the identification and characterization of a new cellular regulator of AAV site-specific integration. TAR RNA loop binding protein 185 (TRP-185), previously reported to associate with human immunodeficiency virus type 1 TAR RNA, binds to AAVS1 DNA. Our data suggest that TRP-185 suppresses AAV integration at the AAVS1 RBS and enhances AAV integration into a region downstream of the RBS. TRP-185 bound to Rep68 directly, changing the Rep68 DNA binding property and stimulating Rep68 helicase activity. We present a model in which TRP-185 changes the specificity of the AAV integration site from the RBS to a downstream region by acting as a molecular chaperone that promotes Rep68 complex formation competent for 3'-->5' DNA helicase activity.
Yamamoto
Noriaki
N
Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
Suzuki
Masato
M
Kawano
Masa-Aki
MA
Inoue
Takamasa
T
Takahashi
Ryou-U
RU
Tsukamoto
Hiroko
H
Enomoto
Teruya
T
Yamaguchi
Yuki
Y
Wada
Tadashi
T
Handa
Hiroshi
H
D001665:Binding Sites; D002888:Chromosomes, Human, Pair 19 / Q000821:virology; D004268:DNA-Binding Proteins / Q000378:metabolism; D000229:Dependovirus / Q000502:physiology*; D015967:Gene Expression Regulation, Viral; D006367:HeLa Cells; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism; D016662:Virus Integration; D000099253:Trans-Activation Responsive RNA-Binding Protein
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; D014764:Viral Proteins; C071598:TARBP1 protein, human; D000099253:Trans-Activation Responsive RNA-Binding Protein