Higher plant lipid transfer protein (LTP) is a class of small molecular weight alkaline single protein that can transfer phospholipids between biomembrane and form the biomembrane in cells. The objective of this study was to understand the func-tion of LTP gene in hulless barley (Hordeum vulgare L. var. nudum Hook. f.). The cDNA sequence of the LTP gene, blt4.9 (Gen-Bank accession number KU170187), was cloned from hulless barley variety Kunlun 12. The full length of blt4.9 cDNA is 720 bp including 348 bp of open reading frame and encodes 115 amino acids. The encoding product is a stable protein with a molecular weight of 11.2 kD, theoretical pI of 9.04, and instability coefficient of 28.41. This protein is rich in Gly, Ala, Leu, and Val amino acids excluding Trp, Glu, and Phe and similar to proteins encoded by other LTP genes. Sequence alignment indicated high simila-rity (98.3%) of protein encoded by blt4.9 from hulless barley and barley (Hordeum vulgare L.). The Real-time PCR assay showed that blt4.9 was up-regulated by 20–30%PEG-6000, 4ºC and 50mmol L-1 ABA and the expression level was higher in the most tolerant variety Handizi than in the most susceptible variety Dama, indicating a possible relationship between stress tolerance and blt4.9 in hulless barley. These results provide basic information in the utilization of LTP genes to improve hulless barley tolerance to abiotic stresses.%为了解脂质转运蛋白基因在青稞中的功能,以青稞品种昆仑12为材料,利用同源克隆得到青稞 blt4.9基因序列(GenBank登录号为KU170187),该基因的cDNA序列全长720 bp,开放阅读框长348 bp,编码115个氨基酸残基,相对分子质量为11.2 kD,理论等电点9.04,不稳定系数为28.41,是一个稳定的蛋白质。blt4.9编码的蛋白绝大多数属于疏水区,没有较大的亲水区。序列比对显示,该基因与大麦 blt4.9基因编码蛋白的同源性最高(98.3%)。Real-time PCR分析结果显示, blt4.9基因在20%~30%PEG-6000、4℃以及50mmol L-1 ABA处理后表达量显著增加,且在抗逆性强的青稞品种(旱地紫)中的表达量高于在抗逆性弱的品种(大麻)中,推测该基因与青稞的抗逆性有关。该研究结果为利用青稞脂质转运蛋白基因改良青稞抗逆性奠定了基础。
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