纪向云 印汉 任小青 李德军 夏志辉

摘  要：小热激蛋白（small heat shock protein， sHSP）是一类胁迫诱导蛋白，不仅参与植物发育还响应生物与非生物胁迫。本研究通过分析转录组数据获得橡胶树12个sHSP基因家族成员。生物信息学分析和表达谱分析结果表明：蛋白保守结构预测显示12个sHSP均具有α-晶体蛋白保守结构域;二级结构预测结果显示，12个sHSP均由α-螺旋、β-转角、延伸链和大量的随机卷曲组成。通过RT-PCR技术分析，结果发现这12个sHSP家族基因在橡胶树不同组织和叶片不同发育时期中表达有明显差异，HbsHSP15.8、HbsHSP16.2、HbsHSP17.3、HbsHSP17.4、HbsHSP17.5b、HbsHSP18.2、HbsHSP18.3、HbsHSP22.5、HbsHSP22.6和HbsHSP23.9在胶乳中高表达，HbsHSP17.4在树皮中高表达，HbsHSP17.5a在樹茎中高表达，HbsHSP25.8则在树叶中表达量最高。乙烯利处理后，12个sHSP家族基因的表达总体呈下降趋势。在不同死皮等级橡胶树中12个sHSP家族基因的表达也具有明显差异，与健康树相比，HbsHSP15.8、HbsHSP17.4、HbsHSP17.5a、HbsHSP17.5b、HbsHSP18.2、HbsHSP18.3、HbsHSP22.6、HbsHSP23.9和HbsHSP25.8在死皮树中的表达量呈下降趋势;HbsHSP16.2、HbsHSP17.3和HbsHSP22.5的表达量呈上升趋势。因此推测橡胶树sHSP家族基因可能参与橡胶树生物与非生物逆境胁迫响应，以及可能在乙烯作用途径中发挥作用。

关键词：橡胶树;小热激蛋白;表达谱分析;胁迫响应

中图分类号：Q813.3      文献标识码：A

Abstract： Small heat shock protein （sHSP） is a type of stress-inducing protein that not only participates in plant development but also responds to biotic and abiotic stresses. In this study， 12 sHSP gene family members of Hevea brasiliensis were obtained by analyzing transcriptome data. The results of bioinformatics analysis and expression profile analysis showed that all 12 sHSPs had α-crystallin conserved domains. The secondary structure prediction results showed that the 12 sHSPs were all composed of α-helix， β-turn， extended strand and a great quantity of random coils. RT-PCR analysis showed the expression of the 12 sHSP family genes in different tissues and developmental stages were significantly different， HbsHSP15.8， HbsHSP16.2， HbsHSP17.3， HbsHSP17.4， HbsHSP17.5b， HbsHSP18.2， HbsHSP18.3， HbsHSP22.5， HbsHSP22.6 and HbsHSP23.9 were highly expressed in latex， HbsHSP17.4 was highly expressed in bark， HbsHSP17.5a was highly expressed in tree stems， and HbsHSP25.8 was highly expressed in leaves. After ethephon treatment， the expression of the 12 sHSPs family genes showed an overall downward trend. The expression of the 12 sHSPs family genes in H. brasiliensis of different tapping panel dryness grades was also significantly different. The expression levels of HbsHSP15.8， HbsHSP17.4， HbsHSP17.5a， HbsHSP17.5b， HbsHSP18.2， HbsHSP18.3， HbsHSP22.6， HbsHSP23.9 and HbsHSP25.8 in diseased trees were significantly lower than that in healthy trees. The expression levels of HbsHSP16.2， HbsHSP17.3 and HbsHSP22.5 were significantly higher than that of healthy trees. It indicates that the sHSP family genes of H. brasiliensis may be involved in the response of rubber tree to biotic and abiotic stresses， and they may play an important role in ethylene pathway.

Keywords： Hevea brasiliensis; small heat shock protein; expression profiles analysis; stress response

DOI： 10.3969/j.issn.1000-2561.2021.12.007

热激蛋白（heat shock protein， HSP）又称热休克蛋白，是指生物体遭受物理、化学和生物等胁迫刺激后，大量表达或者新合成的一类高度保守的蛋白质。HSP广泛存在于各种生物体内，在结构上高度保守，根据分子量大小将HSP分为HSP100、HSP90、HSP70、HSP60、sHSP家族[1]。小热激蛋白（small heat shock protein， sHSP）是植物中含量最丰富的热激蛋白，分子量约为12～ 42 kDa，多数为15～27 kDa。植物sHSP由核内多基因家族编码，并且其sHSP的数量因植物种类而异。……