Genome-wide characterization of the sHsp gene family in Salix suchowensis reveals its functions under different abiotic stresses

作   者：李建波, 张进，贾会霞, 岳志强, 卢孟柱,辛学兵,胡建军
期刊名称：International Journal of Molecular Sciences
影响因子：3.687
卷 期 号：19:3246
页     码：
关键词：small heat shock proteins (sHsp); phylogenetic analysis; gene structure; expression analysis; Salix suchowensis
论文摘要：
Small heat shock proteins (sHsps) function mainly as molecular chaperones that play
vital roles in response to diverse stresses, especially high temperature. However, little is known
about the molecular characteristics and evolutionary history of the sHsp family in Salix suchowensis,
an important bioenergy woody plant. In this study, 35 non-redundant sHsp genes were identified
in S. suchowensis, and they were divided into four subfamilies (C, CP, PX, and MT) based on their
phylogenetic relationships and predicted subcellular localization. Though the gene structure and
conserved motif were relatively conserved, the sequences of the Hsp20 domain were diversified. Eight
paralogous pairs were identified in the Ssu-sHsp family, in which five pairs were generated by tandem
duplication events. Ka/Ks analysis indicated that Ssu-sHsps had undergone purifying selection.
The expression profiles analysis showed Ssu-Hsps tissue-specific expression patterns, and they were
induced by at least one abiotic stress. The expression correlation between two paralogous pairs
(Ssu-sHsp22.2-CV/23.0-CV and 23.8-MT/25.6-MT) were less than 0.6, indicating that they were
divergent during the evolution. Various cis-acting elements related to stress responses, hormone or
development, were detected in the promoter of Ssu-sHsps. Furthermore, the co-expression network
revealed the potential mechanism of Ssu-sHsps under stress tolerance and development. These results
provide a foundation for further functional research on the Ssu-sHsp gene family in S. suchowensis.