Identification and expression analysis of chloroplast ribonucleoproteins (cpRNPs) in Arabidopsis and rice

Chloroplast ribonucleoproteins (cpRNPs) are implicated in splicing, editing, and stability control of chloroplast RNAs as well as in regulating development and stress tolerance. To facilitate a comprehensive understanding of their functions, we carried out a genome-wide identification, curation, and phylogenetic analysis of cpRNP genes in Oryza sativa (rice) and Arabidopsis thaliana (Arabidopsis). Ten cpRNP genes were identified in each of Arabidopsis and rice genomes based on the presence of two RRM (RNA-recognition motif) domains and an N-terminal chloroplast targeting signal peptide in the predicted proteins. These proteins are localized to chloroplasts. Gene expression analysis revealed that cpRNP genes have differential tissue expression patterns and some cpRNP genes are induced by abiotic stresses such as cold, heat, and drought. Taken together, our study provides a comprehensive annotation of the cpRNP gene family and their expression patterns in Arabidopsis and rice which will facilitate further studies on their roles in plant growth and stress responses.