Identification of Fatty Acid Desaturases in Maize and Their Differential Responses to Low and High Temperature.

Xunchao Zhao,Yifei Zhang,Lin He,Jingyu Xu,Xiaoxuan Xu,Shengnan Ge,Yulei Wei,Meng Liu,Jinpeng Wei,Shuren Gao,Dong Ding,Ying Zhao

doi:10.3390/genes10060445

Abstract

Plant fatty acid desaturases (FADs) catalyze the desaturation of fatty acids in various forms and play important roles in regulating fatty acid composition and maintaining membrane fluidity under temperature stress. A total of 30 FADs were identified from a maize genome, including 13 soluble and 17 membrane-bound FADs, which were further classified into two and five sub-groups, respectively, via phylogenetic analysis. Although there is no evolutionary relationship between the soluble and the membrane-bound FADs, they all harbor a highly conserved FA_desaturase domain, and the types and the distributions of conserved motifs are similar within each sub-group. The transcriptome analysis revealed that genes encoding FADs exhibited different expression profiles under cold and heat stresses. The expression of ZmFAD2.1&2.2, ZmFAD7, and ZmSLD1&3 were significantly up-regulated under cold stress; moreover, the expression of ZmFAD2.1&2.3 and ZmSLD1&3 were obviously down-regulated under heat stress. The co-expression analysis demonstrated close correlation among the transcription factors and the significant responsive FAD genes under cold or heat stress. This study helps to understand the roles of plant FADs in temperature stress responses.

Highlights

Plant lipids constitute the lipid double layer structure of biofilms and are the main components of various cell membranes [1]
To identify the whole of fatty acid desaturases (FADs) families in maize, a genome-wide screening was performed by Blastp using the Arabidopsis homologs as query sequences
Not much information is available on the comprehensive FADs families in maize, FAD genes from a range of plant available on the comprehensive FADs families in maize, FAD genes from a range of plant species have been identified and studied [6,49]

Summary

Introduction

Plant lipids constitute the lipid double layer structure of biofilms and are the main components of various cell membranes [1]. Fatty acids are essential constituents in the architecture of biomembranes, and the species and the unsaturation of fatty acid chains are important for membrane functions in plants [2,3,4]. The lipid unsaturation affects the membrane fluidity and is vital for plants to cope with temperature stresses [5]. Two types of FADs have been identified from animals, plants, fungi, and algae; one is soluble stearoyl-ACP (Acyl-carrier protein) desaturase (FAB2, known as SAD), and another is membrane-bound FAD, which desaturates fatty acids that are esterified to various kind of lipids [7,8,9,10].

Methods

Results

Conclusion