Abstract

In plants, the essential roles played by the regulator of chromosome condensation 1 (RCC1) in diverse biological processes, including UV-B (ultraviolet-B radiation) response, hormonal signal transduction, cold tolerance and phenotypic plasticity, have been identified. No comprehensive study on the evolution and function ofRCC1gene family in rice has been carried out. A genome-wide analysis of this gene family is thus required. In this study, a total of 26OsRCC1sunevenly distributed across 10 chromosomes were identified in rice. Based on their phylogenetic relationship and sequence composition, the OsRCC1 family could be classified into six groups. Members within the same group share a similar gene structure and protein motif/domain composition. Gene duplication analysis revealed that segmental duplication might be the main contributor to the expansion of theRCC1gene family in rice. Several cis-regulatory elements (CREs) relevant to light, abscisic acid (ABA) and methyl jasmonate (MeJA) are abundant in the promoters ofOsRCC1s. A large number of microRNA (miRNA) target sites were present inOsRCC1mRNAs. Additionally, we used data from gene microarray and qRT-PCR to analyze the expression ofOsRCC1genes during various developmental stages and under abiotic stress conditions.OsRCC1swere found to be highly expressed in panicles and seeds, and mostOsRCC1swere differentially expressed under abiotic stresses. Taken together, our study provides a systematic characterization of OsRCC1s and preliminarily explores their diversity as well as their biological functions. Evidence demonstrates that OsRCC1s may play vital roles in both development and abiotic stress response. The results presented here lay a foundation for further investigating the functions of OsRCC1s.Keywords:rice;RCC1;evolution;gene expression;abiotic stress