title: Identification of centromeric and telomeric DNA-binding proteins in rice.
abstract: Centromeres and telomeres are DNA/protein complexes and essential functional components of eukaryotic chromosomes. Previous studies have shown that rice centromeres and telomeres are occupied by CentO (rice centromere satellite DNA) satellite and G-rich telomere repeats, respectively. However, the protein components are not fully understood. DNA-binding proteins associated with centromeric or telomeric DNAs will most likely be important for the understanding of centromere and telomere structure and functions. To capture DNA-specific binding proteins, affinity pull-down technique was applied in this study to isolate rice centromeric and telomeric DNA-binding proteins. Fifty-five proteins were identified for their binding affinity to rice CentO repeat, and 80 proteins were identified for their binding to telomere repeat. One CentO-binding protein, Os02g0288200, was demonstrated to bind to CentO specifically by in vitro assay. A conserved domain, DUF573 with unknown functions was identified in this protein, and proven to be responsible for the specific binding to CentO in vitro. Four proteins identified as telomere DNA-binding proteins in this study were reported by different groups previously. These results demonstrate that DNA affinity pull-down technique is effective in the isolation of sequence-specific binding proteins and will be applicable in future studies of centromere and telomere proteins.
authors.affiliation: State Key Laboratory for Agrobiotechnology, Institute of Plant Molecular Biology and Agricultural Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong.
authors.forename: Qi
authors.initials: Q
authors.lastname: He
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Yu
authors.initials: Y
authors.lastname: Xu
authors.forename: Weichang
authors.initials: W
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002503:Centromere / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D012275:Oryza / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D016615:Telomere / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D010940:Plant Proteins