title: A candidate factor that interacts with RF2, a restorer of fertility of Lead rice-type cytoplasmic male sterility in rice.
abstract: BACKGROUND
  The pollen function of cytoplasmic male sterile (CMS) plants is often recovered by the Restorer of fertility (Rf) gene encoded by the nuclear genome. An Rf gene of Lead rice type CMS, Rf2, encodes a small mitochondrial glycine-rich protein. RF2 is expected to function by interacting with other proteins, because RF2 has no motifs except for glycine-rich domain.
  
  
  RESULTS
  To elucidate the protein that interacts with RF2, we performed yeast two-hybrid screening. We identified four genes and named RF2-interacting candidate factors (RIF1 to RIF4). A study of subcellular localization demonstrated that only RIF2 was targeted to mitochondria. A pull-down assay using E. coli-produced recombinant GST-tagged RF2 and His-tagged RIF2 confirmed that RF2 interacted with RIF2. RIF2 encodes ubiquitin domain-containing protein.
  
  
  CONCLUSIONS
  These results suggest that RIF2 is a candidate factor of a fertility restoration complex of RF2.
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, Sendai, 981-8555, Japan, b3ad1210@s.tohoku.ac.jp.
authors.forename: Shinya
authors.initials: S
authors.lastname: Fujii
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Kazama
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Soichi
authors.initials: S
authors.lastname: Kojima
authors.forename: Kinya
authors.initials: K
authors.lastname: Toriyama