类GSK3激酶调控光合相关基因表达和叶绿体发育的分子机制的研究

Plant glycogen synthase kinase 3 (GSK3)，play essential roles in modulating numerous developmental processes, including photosynthetic metabolism and chloroplast development. But the molecular mechanism how GSK3 regulates photosynthesis is not known. The physiological importance of GSK3-like kinases in plants emerged when the functional role of plant GSK3-like kinases represented by BIN2 was the first elucidated GSK3-like kinases in plants in brassinosteroid (BR) signaling. Compared with wild type, BIN2 gain of function/loss of function mutants bin2-1 and bil1bil2bin2-3 displayed changed chlorophyll content. Meanwhile we identified two BIN2 phosphorylated substrates GLK1 and ABI4. We proposed BIN2 regulates photosynthesis by phosphorylating GLK1 and ABI4. Next we will perform kinase assay in vitro and in vivo to detect whether BIN2 can affect GLK1 and ABI4 subcellular localization and transcriptional activity by phosphorylation. Our results therefore will establish a new mechanism by which, two BIN2 substrates, functions to amplify GSK3 in regulating photosynthesis.

植物的类糖原合成酶3（GSK3）在植物发育和应对非生物胁迫过程中具有重要作用。虽然表观遗传学显示类GSK3激酶在植物光合作用和叶绿体发育过程中可能具有重要作用，但是其中的具体分子机制还不清楚。我们前期的研究工作分离出了GSK3激酶BIN2的两个底物，分别为转录因子GLK1和ABI4。与野生型相比，BIN2功能获得型突变植株bin2-1叶片叶绿素含量升高，而BIN2及其同源基因BIL1和BIL2三缺失突变体bin2-3bil1bil2的叶绿素含量减低。因此我们推测BIN2可能通过调控GLK1和ABI4来影响光合相关基因表达和叶绿体发育。我们拟通过研究BIN2是否可以与GLK1和ABI4互作并且通过磷酸化GLK1和ABI4来影响其亚细胞定位和转录活性，来揭示类GSK3激酶对光合基因表达和叶绿体发育调控的分子机制。这些研究对丰富和完善植物细胞调控光合作用和叶绿体发育的多重调控机制具有重要意义。

植物的类糖原合成酶3（GSK3）在植物发育和应对非生物胁迫过程中具有重要作用。虽然表观遗传学显示类GSK3激酶在植物光合作用和叶绿体发育过程中可能具有重要作用，但是其中的具体分子机制还不清楚。我们的研究工作分离出了GSK3激酶BIN2的底物，转录因子GLK1。与野生型相比，BIN2功能获得型突变植株bin2-1叶片叶绿素含量升高，而BIN2及其同源基因BIL1和BIL2三缺失突变体bin2-3bil1bil2的叶绿素含量减低。我们的实验结果表明BIN2通过调控GLK1来影响光合相关基因表达和叶绿体发育。我们发现BIN2与GLK1互作，并且通过磷酸化GLK1来影响其亚细胞定位和转录活性，从而揭示类GSK3激酶对光合基因表达和叶绿体发育调控的分子机制。这些研究对丰富和完善植物细胞调控光合作用和叶绿体发育的多重调控机制具有重要意义。