Genome-Wide Identification and Expression Profiling of the Gene Family Reveals Their Probable Involvement in Abiotic Stress Tolerance in Tomato ( L.).

Protein disulfide isomerases (PDI) and PDI-like proteins catalyze the formation and isomerization of protein disulfide bonds in the endoplasmic reticulum and prevent the buildup of misfolded proteins under abiotic stress conditions. In the present study, we conducted the first comprehensive genome-wide exploration of the gene family in tomato ( L.). We identified 19 tomato genes that were unevenly distributed on 8 of the 12 tomato chromosomes, with segmental duplications detected for 3 paralogous gene pairs. Expression profiling of the genes revealed that most of them were differentially expressed across different organs and developmental stages of the fruit. Furthermore, most of the genes were highly induced by heat, salt, and abscisic acid (ABA) treatments, while relatively few of the genes were induced by cold and nutrient and water deficit (NWD) stresses. The predominant expression of , , , , , and in response to abiotic stress and ABA treatment suggested they play regulatory roles in abiotic stress tolerance in tomato in an ABA-dependent manner. Our results provide new insight into the structure and function of genes and will be helpful for the selection of candidate genes involved in fruit development and abiotic stress tolerance in tomato.