<p>Although the number of sequenced plant genomes has been rapidly increasing, many plant proteins in public databases are recognized as proteins with domains of unknown function (DUF). The domain of unknown function DUF829 family consists of plant proteins with an average length of around 220 residues. In this study, we attempted to uncover the biological functions of four DUF829 members (OsDUF829.1–OsDUF829.4) in rice Nipponbare. We classified these proteins into three groups (group I, II and III) using phylogenetic analysis. Real time polymerase chain reaction (PCR) showed that the expression patterns of the four <i>OsDUF829</i> family members were different in 15 different rice tissues. Under salt and heat stress conditions, the expression level of <i>OsDUF829.2</i> and <i>OsDUF829.4</i> was significantly elevated. Overexpression of <i>OsDUF829.2</i> and <i>OsDUF829.4</i> in <i>Escherichia coli</i> significantly improved the resistance to salt stress. The obtained results provide important implications for further functional studies of the OsDUF829 family in rice.</p
