Regulation of the Activity and Location of Starch-Related Dikinases

淀粉相关二激酶活性和位置的调节

• 批准号: 184352434
• 负责人: Professor Dr. Joerg Fettke
• 金额: --
• 依托单位: Institut für Biochemie und Biologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/184352434?language=en
• 关键词: Regulation; Activity; Location; Starch; Related

The reversible phosphorylation of a low amount of starch-related glucosyl residues is mediated by a concerted action of two plastidial dikinases (glucan, water dikinase [GWD] and phosphoglucan, water dikinase [PWD]) and, at least, two phosphatases (SEX4 and LSF2). The reversible glucan modification is essential for normal starch turn-over and for plant growth. This proposal uses various experimental approaches and focuses on the following aspects: a) GWD catalysis an unexpected high number of phosphotransfer reactions. Previous results have shown that, at least, during the transfer of the gamma-phosphate from ATP to e.g. water an amino acid residue is transiently phosphorylated. Using various truncated and mutated GWD versions and mass spectrometry, this transiently phosphorylated amino acid will be identified. In comparison the phosphotransfer of PWD will be analyzed. b) The glucan properties used by the dikinases will be analyzed. Therefore, various starch and neoamylose fractions will be used and characterized as substrate for the dikinases. In addition the distribution of potential binding sites of GWD and PWD on starches will be analyzed in vitro and in vivo. c) As increasing evidences exist, that GWD is involved in starch synthesis, the contribution of GWD to starch synthesis and formation of starch granule morphology will be analyzed. Therefore, starch granule morphology and surface properties will be investigated in inducible and partially complemented GWD transgenic plants under various light conditions.

少量淀粉相关葡萄糖残基的可逆磷酸化是由两种质体二激酶（葡聚糖、水二激酶 [GWD] 和磷酸葡聚糖、水二激酶 [PWD]）和至少两种磷酸酶（SEX4 和LSF2）。可逆葡聚糖修饰对于正常淀粉周转和植物生长至关重要。该提案使用各种实验方法，重点关注以下方面：a) GWD 催化意外大量的磷酸转移反应。先前的结果表明，至少在 γ-磷酸盐从 ATP 转移到例如 ATP 的过程中。水氨基酸残基被瞬时磷酸化。使用各种截短和突变的 GWD 版本和质谱分析，将鉴定这种瞬时磷酸化的氨基酸。作为比较，将分析 PWD 的磷酸转移。 b) 将分析二激酶所使用的葡聚糖特性。因此，各种淀粉和新直链淀粉级分将被用作二激酶的底物并被表征。此外，还将在体外和体内分析淀粉上 GWD 和 PWD 的潜在结合位点的分布。 c) 随着越来越多的证据表明GWD参与淀粉合成，将分析GWD对淀粉合成和淀粉颗粒形态形成的贡献。因此，将在各种光照条件下研究诱导型和部分补充的GWD转基因植物中的淀粉颗粒形态和表面特性。