Mechanism and biological function of the regulation of cellulose synthesis by light

光调控纤维素合成的机制及生物学功能

• 批准号: 143937308
• 负责人: Dr. Volker Bischoff
• 金额: --
• 依托单位: Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/143937308?language=en
• 关键词: Mechanism; biological; function; regulation; cellulose

Cellulose is the most abundant biopolymer on earth and becomes increasingly studied in basic and applied plant research to promote future industrial applications such as second generation biofuels. In Arabidopsis, primary cellulose is produced by the hexameric cellulose synthase complex that is composed of the cellulose synthases (CESA) 1, 3 and 6 and localizes to the plasma membrane. Mutants in CESA6 show growth defects and cellulose deficiency in the dark-, but not in the light grown hypocotyl. We hypothesize that the rescue of these phenotypes in light is the result of the presence of a light-activated CESA6-related isoform, which might be phosphorylated CESA5. Experimental goals of the present proposal are (1) to analyze the regulation of CESA5 by light, its presence in the primary cellulose synthase complex, its plasma membrane motility and intracellular trafficking by confocal spinning disk microscopy, (2) to link the activation of CESA5 by light to phytochrome-induced phosphorylation by analyzing its phosphorylation state and activity by respectively mass spectrometry and spinning disk microscopy, and (3) to clarify the possible role of CESA5 in quality control of cellulose microfibrils by various microscopy methods and to identify its molecular partners.

纤维素是地球上最丰富的生物聚合物，在基础和应用植物研究中越来越多地被研究，以促进未来的工业应用，如第二代生物燃料。在拟南芥中，初生纤维素由六聚纤维素合酶复合物产生，该复合物由纤维素酶（CESA）1、3和6组成并定位于质膜。CESA 6中的突变体在黑暗中显示出生长缺陷和纤维素缺乏，但在光照下生长的下胚轴中没有。我们假设，光下这些表型的拯救是光激活CESA 6相关亚型存在的结果，该亚型可能是磷酸化的CESA 5。本发明的实验目标是（1）通过共聚焦旋转圆盘显微镜分析光对CESA 5的调节、其在初级纤维素合成酶复合物中的存在、其质膜运动性和细胞内运输，（2）通过分别通过质谱和旋转圆盘显微镜分析其磷酸化状态和活性将光对CESA 5的激活与光敏色素诱导的磷酸化联系起来，（3）通过各种显微镜方法阐明CESA 5在纤维素微纤丝质量控制中的可能作用，并鉴定其分子伴侣。