Abstract:

Thionin-like（Thil）genes possesses activity against pathogenic microorganisms in plant defense system；however，the function of Thil genes is not clear. In order to provide reference for studying its biological function，this study analyzed the sequence composition，gene structure，chromosome distribution，protein conserved domains，phylogenetic tree，gene promoter elements，subcellular localization and expression profile of Thil gene family in barley. Seven barley Thils genes were identified，and they were distributed on chromosome 1, 2, 4, 5 and 6. The gene structure analysis showed that the sequences of the family members were conservative except Thil4. The phylogenetic tree revealed that barley Thil genes were divided into four subfamilies. The results of expression profile analysis demonstrated that the expression of Thil gene varied in different tissues of barley. In general，the expression of Thil gene was very low in the roots and seeds，and the highest in the young leaves. The subcellular localizations of Thil proteins in different members of the family are also different. Thil1 and Thil2 were mainly located in the cell membrane，nucleus and cytoplasm，Thil3 and Thil7 were located in the cell membrane，and Thil6 was located in chloroplast. The Thil gene was associated with plant protection and defense mechanisms. The elements that can stimulate plant protection mechanisms responded most in young leaves. Quantitative RT-PCR（qRT-PCR）results showing the expression of the Thil gene was the highest in young leaves. It can be found that the same members are involved in different developmental processes of plants in the evolutionary process from the subcellular localization experiment.

Key words: barley, thionin-like, gene structure, gene expression profile