Alexander Liza E, Gilbertson Jena S, Xie Bo, Song Zhihong, Nikolau Basil J
Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology Iowa State University Ames IA USA.
Center for Metabolic Biology Iowa State University Ames IA USA.
Plant Direct. 2021 Apr 29;5(4):e00322. doi: 10.1002/pld3.322. eCollection 2021 Apr.
The extensive collection of () and () mutants of maize and Arabidopsis have proven invaluable in dissecting the branched metabolic pathways that support cuticular lipid deposition. This bifurcated pathway integrates a fatty acid elongation-decarbonylative branch and a fatty acid elongation-reductive branch, which collectively has the capacity to generate hundreds of cuticular lipid metabolites. In this study, a combined transgenic and biochemical strategy was implemented to explore and compare the physiological function of three homologous genes, , , and , in the context of this branched pathway. These biochemical characterizations integrated new extraction chromatographic procedures with high spatial resolution mass spectrometric imaging methods to profile the cuticular lipids on developing floral tissues transgenically expressing these transgenes in wild-type or mutant lines of Arabidopsis. Collectively, these datasets establish that both the maize and genes are functional homologs of the Arabidopsis gene. In addition, the dynamic distribution of cuticular lipid deposition follows distinct floral organ localization patterns indicating that the fatty acid elongation-decarbonylative branch of the pathway is differentially localized from the fatty acid elongation-reductive branch of the pathway.
玉米和拟南芥中广泛收集的（）和（）突变体已被证明在剖析支持表皮脂质沉积的分支代谢途径方面具有重要价值。这条分叉途径整合了脂肪酸延伸 - 脱羰基分支和脂肪酸延伸 - 还原分支，它们共同有能力产生数百种表皮脂质代谢物。在本研究中，实施了一种转基因和生化相结合的策略，以在这条分支途径的背景下探索和比较三个同源基因、和的生理功能。这些生化特性将新的提取色谱程序与高空间分辨率质谱成像方法相结合, 以分析在野生型或拟南芥突变体系中转基因表达这些转基因的发育中的花组织上的表皮脂质。总体而言，这些数据集表明玉米基因和基因都是拟南芥基因的功能同源物。此外，表皮脂质沉积的动态分布遵循不同的花器官定位模式，表明该途径的脂肪酸延伸 - 脱羰基分支与该途径的脂肪酸延伸 - 还原分支的定位不同。
