Abstract:In order to explore the characteristics of LEA_2 family members in rice,we characterized 60 LEA_2 family members in the whole genome of rice with bioinformatics,and found they were unevenly distributed on 12 chromosomes. Results of analyzing protein sequence showed that the molecular weight of the LEA_2 proteins were between 16.24 ku and 49.14 ku with isoelectric points ranging from 4.7 to 11.7,and 42 of them tended to be hydrophobic. Results of phylogenetic analysis indicated that rice LEA_2 proteins are classified into five major clades,and proteins in the same clade has similar conservative motifs. Results of analyzing gene structure showed that LEA_2 genes had no or few introns. Results of analyzing promoter sequence showed that there were a large number of cis-elements related to growth and development,hormone signal transduction and stress response in promoter regions of rice LEA_2 genes. Based on the hierarchical cluster analysis of the expression profile and fluorescence quantitative PCR assays, the co-expression of LEA_2 family genes was found to be obvious. Both OsLEA2-2 and OsLEA2-26 were up-regulated and expressed by more than 60 times under drought stress.