title: Genome-wide analysis and expression profiling of half-size ABC protein subgroup G in rice in response to abiotic stress and phytohormone treatments.
abstract: The roles of the proteins encoded by half-size adenosine triphosphate-binding cassette transporter subgroup G (ABCG) genes in abiotic stress responses are starting to be established in the dicot model Arabidopsis thaliana. In the monocot model rice, the functions of most half-size ABCG proteins in abiotic stress responses are unknown. Rcn1/OsABCG5 is an essential transporter for growth and development under abiotic stress, but its molecular function remains largely unclear. Here, we present a comprehensive overview of all 30 half-size ABCG genes in rice, including their gene structures, phylogeny, chromosome locations, and conserved motifs. Phylogenetic analysis revealed that the half-size OsABCG proteins were divided to four classes. All seven rice intronless genes, including Rcn1/OsABCG5, were in Class III, like the 12 intronless ABCG genes of Arabidopsis. The EST and FL-cDNA databases provided expression information for 25 OsABCG genes. Semi-quantitative and quantitative RT-PCR analyses demonstrated that seven OsABCG genes were up-regulated in seedlings, shoots or roots following treatments with abiotic stresses (6, 17, 42 °C, NaCl, or mannitol) and abscisic acid. Another 15 OsABCG genes were up-regulated under at least one of the abiotic stress conditions and other phytohormones besides abscisic acid. Hierarchical clustering analysis of gene expression profiles showed that expression of the OsABCG genes could be classified into four clusters. The Rcn1/OsABCG5 cluster was up-regulated by abscisic acid and included OsABCG2, 3, 13, and 27. The present study will provide a useful reference for further functional analysis of the ABCGs in monocots.
authors.affiliation: Department of Crop Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Matsuda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Funabiki
authors.forename: Kaoru
authors.initials: K
authors.lastname: Furukawa
authors.forename: Nozomi
authors.initials: N
authors.lastname: Komori
authors.forename: Masanori
authors.initials: M
authors.lastname: Koike
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tokuji
authors.forename: Itsuro
authors.initials: I
authors.lastname: Takamure
authors.forename: Kiyoaki
authors.initials: K
authors.lastname: Kato
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D055106:Genome-Wide Association Study; D012275:Oryza / Q000187:drug effects / Q000235:genetics*; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics*; D013312:Stress, Physiological
chemical_list: D018528:ATP-Binding Cassette Transporters; D010937:Plant Growth Regulators; D010940:Plant Proteins