摘　要：硒在植物体中有非常重要的生理生化功能及作用，硫转运蛋白是主动转运硒酸盐的载体蛋白。从谷子基因组数据库中鉴定出SiSULTR2.1基因序列，并进行生物信息学分析及叶面喷施Na2SeO4、Na2SO4表达响应分析，旨在研究谷子中SiSULTR2.1基因的理化性质及Na2SeO4、Na2SO4处理表达响应，为谷子SiSULTR2.1基因的硒、硫转运机制的研究提供理论依据。SiSULTR2.1蛋白分子质量为70 374.55 Da，氨基酸数目为656个，为疏水性、非分泌蛋白，无信号肽，二级结构由α-螺旋、β-折叠和无规则卷曲构成，包含硫转运蛋白所特有的STAS结构域和Sulfate-transp结构域。实时荧光定量RCR（qRT-PCR）分析发现，SiSULTR2.1具有组织表达特异性，且在谷子茎、叶片中表达量较高。Na2SeO4、Na2SO4处理后的0～96 h内均可诱导SiSULTR2.1表达。SiSULTR2.1对Na2SO4的响应较快，在12 h时达到峰值，对Na2SeO4响应较慢，处理后24 h时表达量高于对照组，之后持续增加。这一研究结果为进一步阐述SiSULTR2.1基因的硒、硫转运机制提供了依据。
关键词：谷子；硫转运蛋白；表达分析；Na2SeO4；Na2SO4
中图分类号：S515      　　　　　  文献标志码：A             DOI：10.3969/j.issn.1007-7146.2022.02.009

Abstract: Selenium plays a very important physiological and biochemical role in plants, selenates are actively transported by SULTR carrier proteins. SiSULTR2.1 gene sequence was identified from the millet genome database, bioinformatics analysis of SiSULTR2.1 was performed and expression response of leaves sprayed with Na2SeO4 and Na2SO4 was analyzed. The objective of this study was to investigate the physicochemical properties of SiSULTR2.1 gene and its expression response to Na2SeO4 and Na2SO4 treatment in millet, and to provide theoretical basis for the study of selenium and sulfur transport mechanism of SiSULTR2.1 gene in millet. SiSULTR2.1 was hydrophobic, non-secretory protein, without signal peptide, 70 374.55 Da molecular weight, 656 amino acids and its secondary structure is composed of α-helix, β-folding and random crimp, contains STAS domain and sulfate-transp domain that are characteristic of sulfur transporter. Quantitative real-time PCR (qRT-PCR) analysis showed that SiSULTR2.1 has obvious tissue expression specificity, with the higher expression level in the stems and leaves. SiSULTR2.1 could be detected in all tested tissues of millet plant and expression was induced by Na2SeO4 and Na2SO4 for 0 ～ 96 h, SiSULTR2.1 has a faster response to Na2SO4, reaching its peak at 12 h, and a slower response to Na2SeO4. The results would provide a basis for further elucidating the mechanism of SiSULTR2.1 gene in Se and S transport.
Key words: millet; sulfate transporter; expression analysis; Na2SeO4; Na2SO4
（Acta Laser Biology Sinica, 2022, 31(2): 157-164）