Genome-wide analysis of gibberellin-dioxygenases genes in rice

Abstract

Background Gibberellins (GAs), a pivotal plant hormone, play fundamental roles in plant development and growth. In rice, gibberellin-dioxygenases (GAoxes), OsGA20ox, OsGA3ox and OsGA2ox, are involved in the biosynthesis and deactivation of gibberellins. However, a comprehensive genome-wide analysis of gibberellin-dioxygenases genes is still uncovered.Results In this study, a total of 95 candidate OsGAox genes were found and 19 OsGAox genes were further analyzed. Results of phylogenetic tree showed that the OsGAox genes in Arabidopsis and rice were divided into four subgroups and shared some common features. Furthermore, analysis of gene structure and conserved motifs revealed that splicing phase and motifs were well conserved during the evolution of GAox genes in Arabidopsis and rice, and some specific motifs still need to be further studied. Exploration of expression profiles indicated that most of OsGAox genes exhibited tissue-specific expression patterns, implied their complicated functions. Moreover, the expression patterns of these genes under GA 3 and PAC treatment were investigated, and result showed that some genes, OsGA2ox3, OsGA2ox5, OsGA2ox7, OsGA2ox9, OsGA20ox2, and OsGA20ox4, may play a major role in GA homeostasis to cope with exogenous GA.Conclusions Our study provided a comprehensive analysis of the OsGAox gene family. Splicing characteristics and conserved motifs indicated the evolutionary conserved function in plants. Expression profiles indicated that each OsGAox gene has complicated and special functions. Although plenty of GAoxes were involved in the endogenous GA metabolism, only some of them acted in response to the exogenous GA treatment, which provided available information for researchers to manipulate the chemical GAs to improve the plant architecture and production.