Our work is focused on the identification and functional characterization of orphan genes from coffee, which may have a high potential for innovation and biotechnological applications. This study presents data obtained for one of these orphan genes, called CcUNK8 (UNK for Unknown), previously identified as a candidate gene for drought tolerance in coffee. Aiming to identify the functions of CcUNK8 protein, the cDNA of this gene was cloned in an expression vector used to transformed embryogenic callus of Setaria viridis by Agrobacterium tumefaciens. Thirteen T0transformed plants of S. viridis were selected and the presence of the inserted T-DNA was confirmed by PCR. Leaf CcUNK8gene expression was analyzed by RT-qPCR and presented a variation between transformed plants. Physiological and phenological analyses (with or without drought) were performed in order to see if CcUNK8expression enhanced drought tolerance in S. viridis.