OsLEA3-2 in Salt and Drought Tolerance Response Figure 7. Drought-treatment assay of wild type and transgenic rice plants. One month old seedlings of the wild type cultivar and transgenic plants (A) were treated with drought stress (without irrigation) for 20 days (B), then irrigated with water and grown for 10 days (C), and one month (D). 1, wild type; 2, transgenic line 10; 3, transgenic line 30. Each container had six plants. doi:10.1371/journal.pone.0045117.g007 hydrophilic, glycine-rich proteins that are thought to function through the maintenance of protein or membrane structure, sequestration of ions, or as molecular chaperones to help prevent the formation of damaging protein aggregates [24,27,28]. In this study, we cloned a LEA protein gene OsLEA3-2 in Oryza sativa and found it to be expressed in late embryo stage and could be induced by abiotic stresses. The OsLEA3-2 gene is located in the nucleus (Fig. 3), along with MsLEA3-1 [29], while the cotton group 3 LEA protein D-7 is present only in the cytosol [13]. Different group 3 LEA proteins have different subcellular locations, which indicate that the group 3 LEA proteins have different functions. The OsLEA3-2 gene enhanced salt and osmotic stress tolerance when expressed in Saccharomyces crevisiae. Ectopic expressions of the LEA protein genes in S. crevisiae or E. coli improve the growth performance of the transformant under abiotic stresses [20,30,31,32]. The growth performance of S. cerevisiae cells that expressed le4, le25, or HVA1 [30,31] was improved under salt stress conditions as compared with the control, however, no improved Figure 8. Effect of drought-stress on wild type and transgenic rice plants. One month old seedlings of the wild type cultivar and transgenic plants (A) were treated with drought stress (without irrigation) for 18 days (B), then irrigated with water and grown for 10 days (C). (D) Spikes from survived ZH11 and transgenic line L10. (E) Survival ratio of the rice plants. (F) Statistic analysis of the grains. Three and ten spikes were analyzed for ZH11 and transgenic line L10, respectively. **P,0.01 shown above the bar reprent results significantly different from wild type. Effect of drought- stress was assayed in triplicate. doi:10.1371/journal.pone.0045117.g008 PLOS ONE | www.plosone.org 9 September 2012 | Volume 7 | Issue 9 | e45117