Abstract:The late embryogenesis abundant protein gene OoY2K4 that participated in different stress response was isolated from the transcriptome database of Oxytropis ochrocephala Bunge by homologous cloning in this study. OoY2K4 contained an open reading frame(ORF)of 786 bp and encoded a protein of 261 amino acid residues, and was considered to be a member of Y2K4 protein families for containing a conservative 2 Y fragments and 4 K pieces. OoY2K4 protein did not have the transmembrane domains, signal peptide, and had strong hydrophilic, and contained one glycosylation sites and seventeen phosphorylation sites. Subcellular localization prediction and experiment showed that OoY2K4 protein was localized to cytoplasm. Multiple sequence alignment found that OoY2K4 protein had highly conservative LEAⅡ sequence with other species. A homology analysis based on the deduced amino sequence indicated that OoY2K4 protein had a closer relationship with LEAⅡ from Trifolium repens, Medicago truncutula and Medicago sativa than that from other plants. The expression patterns of OoY2K4 under abiotic stress and exogenous hormone treatments were investigated by qRTPCR and the results showed that drought and salt stresses could significantly affect the expression of OoY2K4, while cold stress could not; Hormone treatments could make OoY2K4 express efficiently, in which OoY2K4 gene expression induced by abscisic acid is of most significance. All results above speculated that OoY2K4 gene may be involved in the response to drought and high salt stress by relying on ABA signaling pathway.