title: Identification and characterization of the RCI2 gene family in maize (Zea mays).
abstract: Rare-cold-inducible (RCI2) genes are structurally conserved members that encode small, highly hydrophobic proteins involved in response to various abiotic stresses. Phylogenetic and functional analyses of these genes have been conducted in Arabidopsis, but an extensive investigation of the RCI2 gene family has not yet been carried out in maize. In the present study, 10 RCI2 genes were identified in a fully sequenced maize genome. Structural characterization and expression pattern analysis of 10 ZmRCI2s (Zea mays RCI2 genes) were subsequently determined. Sequence and phylogenetic analyses indicated that ZmRCI2s are highly conserved, and most of them could be grouped with their orthologues from other organisms. Chromosomal location analysis indicated that ZmRCI2s were distributed unevenly on seven chromosomes with two segmental duplication events, suggesting that maize RCI2 gene family is an evolutionarily conserved family. Putative stress-responsive cis-elements were detected in the 2-kb promoter regions of the 10 ZmRCI2s. In addition, the 10 ZmRCI2s showed different expression patterns in maize development based on transcriptome analysis. Further, microarray and quantitative real-time PCR (qRT-PCR) analysis showed that each maize RCI2 genes were responsive to drought stress, suggesting their important roles in drought stress response. The results of this work provide a basis for future cloning and application studies of maize RCI2 genes.
authors.affiliation: Key Laboratory of Crop Biology of Anhui Province, School of Life Sciences, Anhui Agricultural University, Hefei 230036, People's Republic of China. zhusuwen@126.com.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Haiqing
authors.initials: H
authors.lastname: Tong
authors.forename: Ronghao
authors.initials: R
authors.lastname: Cai
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Peng
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Li
authors.forename: Defang
authors.initials: D
authors.lastname: Gan
authors.forename: Suwen
authors.initials: S
authors.lastname: Zhu
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D010802:Phylogeny; D003313:Zea mays / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; C108982:RCI2A protein, Arabidopsis