Intracellular Communication Mechanism for Organization of Photosynthetic Functions through Plant Body

1.鉴定了一个新的具有蛋白酶活性的叶绿体类核DNA结合蛋白CND 41，并对其在衰老过程中Rubisco降解、分生组织中叶绿体发育、赤霉素生物合成调控生长等方面的功能进行了研究.利用叶绿体DNA微阵列技术，发现叶绿体RNA结合蛋白（cpRNP）对基质积累转录本具有RNA稳定活性，并鉴定了靶RNA种类。阐明了C4玉米叶肉细胞和维管束鞘细胞通过Fd分子围绕光系统I进行电子传递以控制碳氮代谢的机制。解析了Fd/FNR复合物的三维结构，揭示了Fd/FNR复合物调控电子转移的分子机理.以蓝细菌为模型，阐明了碳/氮代谢调控的分子机制，2-酮戊二酸被证明是NtcA转录激活所必需的氮同化基因（全局氮调节基因）;硝酸盐转运蛋白的调节域，参与在氮充足条件下转运活性的下调，被鉴定并显示与PII（glnB基因产物）一致地控制转运活性。通过选择性剪接调节过氧化物酶体羟基丙酮酸还原酶和叶绿体抗坏血酸过氧化物酶的亚细胞定位，并分离出参与剪接的反式作用因子。已经分离出了几个β-氧化途径缺陷的突变体，并且已经相当清楚地阐明了在乙醛酸体中的脂质降解机制。

1. A novel chloroplast nucleoid DNA-binding protein with protease activity, CND41, has been identified and its multiple functions in Rubisco degradation during senescence, chloroplast development in meristem, growth regulation via gibberellin biosynthesis and so on were characterized.2. The RNA-stablizing activity of chloroplastic RNA-binding proteins (cpRNP) on stroma-accumulating transcripts was found and the target RNA species were identified using chloroplast DNA-microarray.3. The mechanism of electron transfer around Photosystem I through specific Fd molecules for mesophyll and bundle sheath cells in C4 maize plants was clarified to control the carbon/nitrogen metabolism. Three dimensional structure of Fd/FNR complex was resolved to declare the molecular mechanism of the regulation of electron transfer.4. Using cyanobacterium as a model, the molecular mechanism of the control of carbon/nitrogen metabolism was clarified ; 2-oxoglutarate was shown to be essential for transcriptional activation by NtcA (the global nitrogen regulator) of the N assimilation genes ; The regulatory domain of the nitrate transporter, involved in downregulation of the transport activity under N-replete conditions, was identified and shown to control the transport activity in concert with PII (the glnB gene product).5. Regulation of subcellular localization of peroxisomal hydroxypyruvate reductase and chloroplastic ascorbate peroxidase by alternative splicing was established and the trans-acting factor involved in the splicing was isolated. Several mutants with defects in beta-oxidation pathway have been isolated and the mechanism in lipid degradation in glyoxisome has been considerably clarified.