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作者	单位
焦中发，王晓腾，丁帅静，吴玉杰，景姝涵，张莉，孟晓丹，孟凡荣，李永春	(1.河南农业大学农学院/国家小麦工程技术研究中心，河南郑州 450046 2.河南农业大学生命科学学院，河南郑州 450046)

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中文摘要:

硫氧还蛋白是一类在植物中普遍存在的氧化还原调控蛋白，在植物生长发育过程中发挥重要调控功能。为了探讨小麦硫氧还蛋白TaTrxh10的生物学功能，系统分析了该蛋白的序列特征、三维结构及其基因表达模式，并将该蛋白原核表达后进行了其对二硫键还原活性的体外鉴定。蛋白序列特征分析显示，小麦TaTrxh10包含3个成员，分别由3个同源基因TaTrxh10-A、TaTrxh10-B和TaTrxh10-D编码；3个成员均包含143 个氨基酸，序列一致性为94.4%，且具有经典的硫氧还蛋白保守结构域和催化活性中心（WCGPC）。蛋白高级结构分析显示，TaTrxh10可形成由5个β-折叠和4个α-螺旋组成的三明治型特定空间结构。基因表达特性分析发现，TaTrxh10的3个同源基因在小麦根、茎和叶中的表达量极低，在子房和成熟种子中有较低水平的表达，而在成熟花粉中高表达。利用DTNB进行的硫氧还蛋白还原活性鉴定表明，TaTrxh10的3个成员均具有催化二硫键还原的功能，不过其还原活性在3个成员间存在一定差异；在较低浓度硫氧还蛋白的反应体系中，TaTrxh10-D的催化活性最高，TaTrxh10-B次之。以上结果表明，小麦TaTrxh10是一类在花粉中特异表达的有活性的氧化还原调控蛋白，这为进一步探讨小麦中依赖于氧化还原的发育调控机制提供了重要信息。

英文摘要:

Thioredoxins are a class of redox regulatory proteins widely present in plants, which play crucial roles in plant growth and development. To investigate the biological functions of the wheat thioredoxin TaTrxh10, we systematically analyzed its sequence characteristics, three-dimensional structure, and gene expression patterns. The protein was expressed in a prokaryotic system, and its disulfide bond reduction activity was validated in vitro. Sequence analysis revealed that wheat TaTrxh10 comprises three family members encoded by three homoeologous genes: TaTrxh10-A, TaTrxh10-B, and TaTrxh10-D. All three TaTrxh10 family members consist of 143 amino acids, with a sequence identity of 94.4%, and contain the classic thioredoxin conserved domain and catalytic active center(WCGPC). Protein structural analysis demonstrated that TaTrxh10 can fold into a sandwich-like spatial structure composed of five β-sheets and four α-helices. Gene expression analysis indicated that the three homoeologous genes of TaTrxh10 are expressed at very low levels in roots, stems, and leaves, and at relatively lower levels in the ovary and mature seeds; however, they are highly expressed in mature pollens. The thioredoxin reduction activity assay using DTNB demonstrated that all three family members of TaTrxh10 possess the ability to catalyze disulfide bond reduction, but their reduction activities varied among the members. In reaction systems with lower thioredoxin concentrations, TaTrxh10-D exhibited the highest catalytic activity, followed by TaTrxh10-B. These results indicate that wheat TaTrxh10 represents a class of active redox regulatory proteins specifically expressed in pollen, which provides important insights for further exploration of redox-dependent developmental regulatory mechanisms in wheat.

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