Molecular characterization and function analysis of the rice OsDUF1191 family

Abstract Many proteins in public databases are recognized as proteins with domains of unknown function (DUF). DUF1191 is such a protein family that consists of plant proteins with unknown function. In this study, we analyzed the basic information of four OsDUF1191 members (OsDUF1191.1–OsDUF1191.4) in rice Nipponbare. OsDUF1191 family members can be divided into four categories by phylogenetic analysis. In order to find out whether these members have tissue-specific expression preference, we used real-time polymerase chain reaction to examine the expression in 15 distinct rice tissues. We found that OSDUF1191.1 was preferentially expressed in the roots. The expression of the four OsDUF1191 members under various abiotic stress and abscisic acid (ABA) conditions was also examined. The expression of OsDUF1191.4 was significantly (p？<？0.01) upregulated under heat stress conditions. Overexpression of OsDUF1191.4 in Escherichia coli led to a significant enhancement of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD) activities, and improved bacterial resistance to heat stress. The results can provide new insights into the function of the OsDUF1191 family in rice