地黃氧-酰基轉移酶WSD基因的鑒定與表達分析.

Plant wax ester synthase catalyzes the synthesis of wax esters from long-chain alcohols and fatty acids, and plays very important roles in plant wax synthesis and some resistances to drought, pathogenic bacteria, ultraviolet radiation, cold and insect invasion and other environmental stresses; cadmium (Cd) is one of the toxic heavy metals with the highest content in environment, and seriously threatens plant growth, development, quality, yield, and plant food safety. In order to explore the Cd stress expressions of wax ester synthase genes in Rehmannia glutinosa, we identified its wax ester synthase genes from its full-length transcriptome sequencing data, analyzed both physiochemical properties, phytogenetic trees and conserved domains with bioinformatics methods, and tissue expressions and Cd stress expressions using qRT-PCR. The results were as follows: (1) Two wax ester synthase genes, named as RgOATWSD1 and RgOATWSD2, were identified, whose coding proteins were unstable hydrophobic proteins with amino acid lengths of 463 aa and 473 aa, isoelectric points of 8.86 and 9.34 and molecular weights of 51.31 kD and 52.49 kD, respectively. (2) Both proteins contained a conserved acyl＿WS＿DGAT domain and DUF1298 superfamily, in which the former accounted for 92.65% to 94.50% of the amino acid sequence. (3) Both proteins were located in the endoplasmic reticulum and both secondary structures were mainly composed of random coil and α-helix; RgOATWSD2 was not transmembrane protein but RgOATWSD1. (4) Both were differentially expressed in the roots, stems and leaves of R. glutinosa plants. (5) Both expressions were highly responsive to Cd stress, but both expression change trends were different under Cd stress. This study identifies two wax ester synthase genes in response to Cd stress, and lays a foundation for further research on Cd stress expression and other functions of RgOATWSD. [ABSTRACT FROM AUTHOR]

植物蠟酯合成酶催化長鏈醇和長鏈脂肪酸合成蠟酯，對植物蠟質合成及其抗旱、抗致病菌襲擊和紫外輻射、抗寒和昆蟲侵害等環境脅迫具有非常重要的作用；鎘是環境中含量最高的有毒重金屬之一，嚴重威脅植物的生長發育、質量、產量和食用安全。為研究地黃蠟酯合成酶基因鎘脅迫表達，該文從地黃全長轉錄組測序數據中鑒定其成員，并用生物信息學技術與qRT-PCR對其編碼蛋白質的理化性質、系統進化和保守結構域及其組織表達與鎘脅迫表達進行分析。結果表明：（1）鑒定出兩個蠟酯合成酶基因RgOATWSD1與RgOATWSD2,其編碼蛋白質的長度、理論等電點和相對分子量依次為463 aa與473 aa、8.86與9.34、51.31 kD與52.49 kD,均為不穩定蛋白。（2）二者均具有acyl＿WS＿DGAT保守域與DUF1298超家族，前者占其氨基酸序列的92.65%～94.50%。（3）二者均定位于內質網中，二級結構以無規卷曲與α螺旋為主；RgOATWSD1為跨膜蛋白，而RgOATWSD2不是。（4）二者均在地黃根、莖、葉中差異表達。（5）二者表達均受鎘脅迫誘導，但其表達變化趨勢不同。該研究鑒定了兩個鎘脅迫應答反應的蠟酯合成酶基因，為地黃RgOATWSD的鎘脅迫表達及功能研究奠定了基礎。 [ABSTRACT FROM AUTHOR]