吳屯楊PwHB7基因的克隆及生物信息學(xué)分析

摘" " 要：為探究吳屯楊PwHB7基因的生物學(xué)特征及功能，以吳屯楊為材料，利用RT-PCR技術(shù)克隆吳屯楊PwHB7基因的cDNA全長序列，并通過生物信息學(xué)方法分析PwHB7全長序列的特征。結(jié)果表明：吳屯楊PwHB7基因開放閱讀框（open reading frame， ORF）長度為717 bp，編碼238 個氨基酸。二級結(jié)構(gòu)預(yù)測表明：PwHB7蛋白主要由α螺旋、無規(guī)則卷曲、延伸鏈、β轉(zhuǎn)角組成。理化性質(zhì)分析表明：該蛋白由C、H、O、N、S組成，理論等電點為4.93，脂肪指數(shù)為60.67。跨膜區(qū)分析表明：該蛋白為非跨膜蛋白。磷酸化位點分析表明：絲氨酸、蘇氨酸和酪氨酸可能成為磷酸化位點。系統(tǒng)發(fā)育樹分析表明：PwHB7基因與毛果楊PtHB7基因的親緣關(guān)系最近。該結(jié)果為解析PwHB7基因響應(yīng)干旱脅迫的分子機制奠定了基礎(chǔ)，為吳屯楊抗旱育種提供新思路。

關(guān)鍵詞：吳屯楊；PwHB7基因；克隆；序列分析

中圖分類號：S792.11" " " " 文獻標(biāo)識碼：A" " " " DOI 編碼：10.3969/j.issn.1006－6500.2024.06.001

Cloning and Bioinformatics Analysis of PwHB7 Gene in Populus wutunensis

ZHANG Ke， SUN Jingliang， LI Guojiao， JIN Bozhong， HU Yurui， XING Xiaoyu

（College of Environment and Resources， Dalian Minzu University， Dalian， Liaoning 116600， China）

Abstract：To explore the biological characteristics and functions of the PwHB7 gene in Populus wutunensis， this study used Populus wutunensis as the material， cloned the cDNA full-length sequence of the PwHB7 gene using RT-PCR technology， and analyzed the characteristics of the PwHB7 full-length sequence through bioinformatics methods. The results showed that the open reading frame （ORF） length of the PwHB7 gene in Populus wutunensis was 717 bp， encoding 238 amino acids. Secondary structure prediction indicates that PwHB7 protein was mainly composed of α-helix， irregular coil， extended chain， and β-turn. Physical and chemical analysis showed that the protein was composed of C， H， O， N， and S components， with a theoretical isoelectric point of 4.93 and a fat index of 60.67. Transmembrane analysis indicated that the protein was a non transmembrane protein. Phosphorylation site analysis suggested that serine， threonine， and tyrosine mighot become phosphorylation sites. Phylogenetic tree analysis showed that the PwHB7 gene had the closest genetic relationship with Populus trichocarpa PtHB7. This result lays the foundation for analyzing the molecular mechanism of PwHB7 gene's response to drought stress and provided new ideas for drought resistant breeding of Populus wutunensis.

Key words： Populus wutunensis; PwHB7 gene; cloning; sequence analysis

同源異型域-亮氨酸拉鏈蛋白（Homeodomain-leucine Zipper，HD-Zip）是一類HD轉(zhuǎn)錄因子，也是一類高等植物中特有的轉(zhuǎn)錄因子，其特征為包含一個同源異型域（Homeodomain，HD）和一個亮氨酸拉鏈（Leucine Zipper，LZ）。根據(jù)氨基酸序列同源性的差異，植物中 HD-Zip 轉(zhuǎn)錄因子可分為四大類亞家族，分別是 HD-Zip I、HD-Zip II、HD-Zip III 和 HD-Zip IV[1]，其中第Ⅰ類和第Ⅱ類的轉(zhuǎn)錄因子較多。HD-Zip Ⅰ亞家族的蛋白相對其他家族更簡單，該類家族C端存在的AHA保守序列使其形成雙親螺旋結(jié)構(gòu)，并且?guī)в须姾桑笴端具有激活轉(zhuǎn)錄功能，與非生物脅迫、脫落酸（abscisic acid，ABA）應(yīng)答、胚胎發(fā)生等有緊密的關(guān)聯(lián)[2]。HD-Zip Ⅱ亞家族蛋白N末端存在保守的L×L×L結(jié)構(gòu)域（Leu×Leu×Leu）和ZIBEL（zinc finger BEL1-like homeodomain）結(jié)構(gòu)域[3]，使其與光形態(tài)建成和生長素應(yīng)答等有關(guān)聯(lián)。而HD-Zip Ⅲ與HD-Zip Ⅳ亞家族都有START（steroidogenic acute regulatory protein-related lipid transfer）和HD-SAD（START-adjacent domain）結(jié)構(gòu)域[4-5]，主要控制葉的發(fā)育、胚胎和植物分生組織的發(fā)育，參與花青素的積累、根的生長等[6]。……