LAUSR

Abstract Small heat shock proteins (sHSPs) possess major roles in plant defense mechanisms towards abiotic stresses. sHSPs act as molecular chaperones providing the necessary tools to sustain cellular homeostasis under adverse conditions. sHSP genes display specific expression signatures, which depend on tissue-specificity, developmental stage and the nature of the abiotic stress. Despite the fact that Ricinus communis is an important oilseed crop with large socioeconomic impact on small family farmers in semi-arid regions worldwide, the characterization of RcsHSP genes and their possible contribution to plant survival under harsh environmental conditions has not been addressed. Hence, this study aimed at characterizing the R. communis sHSP subfamily, through phylogeny, gene structure, duplication, and expression profile analysis, as well as by characterizing Arabidopsis thaliana seeds overexpressing RcsHSP genes. We identified 41 RcsHSP genes with the α-crystallin domain and compatible molecular weight (