蒺藜苜蓿MtDWF1基因克隆、亚细胞定位及表达特征分析

Delta24-甾醇还原酶(Delta24-sterol reductase, DWF1)是油菜素内酯(Brassinosteroide, BR)合成途径中的关键酶，在植物生长发育中起着关键性的作用。为了研究DWF1基因在蒺藜苜蓿(Medicago truncatula)中的功能，本试验从蒺藜苜蓿R108中克隆MtDWF1基因全长序列，该基因开放阅读框(ORF)1 704 bp,编码567个氨基酸，分子量65.911 kD,理论等电点为8.53。亚细胞定位显示，该蛋白定位于细胞质内。进化分析表明，蒺藜苜蓿MtDWF1蛋白与鹰嘴豆(Cicer arietinum)、红三叶(Trifolium pratense)及豌豆(Pisum sativum)亲缘关系较为接近。MtDWF1基因在蒺藜苜蓿根、茎、叶中均有表达，在茎和叶中的表达水平较高。外源激素脱落酸(Abscisic acid, ABA)能够明显提高MtDWF1表达，水杨酸(Salicylic acid, SA)能够显著降低MtDWF1表达水平。同时，经油菜素内酯诱导后，MtDWF1表达水平整体呈现增加趋势。本研究为进一步探索MtDWF...

Cloning,Subcellular Localization and Expression Pattern of MtDWF1 Gene in Medicago truncatula

Delta24-sterol reductase (DWF1) is a crucial enzyme in the biosynthesis of brassinosteroids and has a significant regulation on plant growth and development. To examine the function of the DWF1 gene in Medicago truncatula,the full-length sequence of the MtDWF1 gene was cloned from M. truncatula (R108). The open reading frame of MtDWF1 was found to be 1 704 bp in length and encoded a peptide of 567 amino acids with a molecular weight of 65.911 kDa and a predicted isoelectric point of 8.53. The protein of the MtDWF1 was localized in the cytoplasm as determined by subcellular localization analysis. Evolutionary analysis indicated that the MtDWF1 protein of M. truncatula is closely related to those of Cicer arietinum,Trifolium pratense,and Pisum sativum. The MtDWF1 gene was expressed in the roots,stems,and leaves of M. truncatula,with higher expression levels observed in stems and leaves than that in roots. Exogenous application of abscisic acid (ABA) caused the MtDWF1 expression significantly increased,while salicylic acid (SA) significantly reduced. Brassinosterol (BR) treatment resulted in an overall increase of MtDWF1 expression. This study provides a foundation for further investigating on the role of the MtDWF1 gene in M. truncatula development.