School of Grassland Science, Beijing Forestry University, Beijing 100083, China.
Int J Mol Sci. 2022 May 27;23(11):6032. doi: 10.3390/ijms23116032.
The NYC-like (NOL) enzyme is considered as an essential enzyme for chlorophyll degradation, which catalyzes the formation of 7-hydroxymethyl chlorophyll a from chlorophyll . The gene was cloned from with a completed coding sequence of 981-bp in length, encoding 326 amino acids. ZjNOL was localized on the stroma side of the thylakoid membrane, and co-localized with ZjNYC in the chloroplasts. Multiple photoregulatory elements and hormone regulatory elements were identified in the promoter region of the ZjNOL gene, and the expression level of the gene was dramatically up-regulated in senescence leaves, which were regulated by a variety of plant hormones. 's ectopic expression in creeping bentgrass produced yellow leaves, thicker cortex, and smaller vascular column cells. Additionally, transgenic plants exhibited morphological alterations in their chloroplast structure, and the number of grana and thylakoids per grana stack reduced dramatically. Transgenic plants also had a lower photosynthetic rate and Fm/Fv than the control. The transgenic plants displayed a decreased chlorophyll content and a greater rate of ion leakage. The properties and activities of will serve as a foundation for future research into gene functions and regulatory processes.
NYC 样(NOL)酶被认为是叶绿素降解的必需酶,它催化叶绿素形成 7-羟甲基叶绿素 a。该基因是从 克隆而来的,其完整的编码序列长 981bp,编码 326 个氨基酸。ZjNOL 位于类囊体膜的基质侧,与叶绿体中的 ZjNYC 共定位。ZjNOL 基因启动子区鉴定出多种光调控元件和激素调控元件,基因的表达水平在衰老叶片中显著上调,受多种植物激素调控。在匍匐翦股颖中的异位表达导致叶片发黄、皮层变厚、维管束细胞变小。此外,转基因植物的叶绿体结构发生形态改变,每个基粒堆叠的类囊体和基粒数量显著减少。转基因植物的光合速率和 Fv/Fm 也低于对照。转基因植物的叶绿素含量降低,离子泄漏率增加。NOL 的特性和活性将为未来研究基因功能和调控过程奠定基础。