title: Genome-wide identification and characterization of maize expansin genes expressed in endosperm.
abstract: By promoting cell wall loosening, expansins contribute to cell enlargement during various developmental processes. Nevertheless, the role of expansins in the expansion and development of endosperm--a major seed component whose cell size is significantly associated with grain yield--is poorly understood. To explore associated biological processes and the evolution of expansins in maize, we performed a systematic analysis of the expansin gene family encompassing gene structure, phylogeny, chromosomal location, gene duplication, and gene ontology. A total of 88 maize expansin genes (ZmEXPs) were identified and categorized into three subfamilies according to their phylogenetic relationships. Expression patterns of ZmEXPs were also investigated in nine different tissues by semi-quantitative RT-PCR. The expression of eight ZmEXPs was detected in endosperm, with five showing endosperm-specific expression. Quantitative RT-PCR was used to analyze expression patterns of the eight ZmEXPs in endosperm (10 days after pollination) under abscisic acid (ABA) and gibberellic acid (GA3) treatments. All eight ZmEXPs were found to be significantly regulated by ABA and GA3 in endosperm, suggesting important roles for these hormones in the regulation of ZmEXPs during endosperm development. Our results provide essential information for ZmEXPs cloning and functional exploration, which will assist research on expansin-related mechanisms and contribute to future enhancement of maize grain yield.
authors.affiliation: Key Laboratory of Crop Biology of Anhui Province, School of Life Sciences, Anhui Agricultural University, Hefei, 230031, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Hanwei
authors.initials: H
authors.lastname: Yan
authors.forename: Weijun
authors.initials: W
authors.lastname: Chen
authors.forename: Jinyang
authors.initials: J
authors.lastname: Liu
authors.forename: Cuiping
authors.initials: C
authors.lastname: Jiang
authors.forename: Haiyang
authors.initials: H
authors.lastname: Jiang
authors.forename: Suwen
authors.initials: S
authors.lastname: Zhu
authors.forename: Beijiu
authors.initials: B
authors.lastname: Cheng
mesh_terms: D032461:Chromosomes, Plant; D056625:Endosperm / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D020131:Genes, Duplicate; D017343:Genes, Plant; D018745:Genome, Plant; D010940:Plant Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; C095825:expansin protein, plant