11月10日 杨贞标:Mechanisms overarching rapid tip growth, growth guidance, and penetrative growth of pollen tubes


报告题目:Mechanisms overarching rapid tip growth, growth guidance, and penetrative growth of pollen tubes
报告人:杨贞标,美国加州大学河滨分校植物系教授
主持人:许玲 / 翁杰敏 教授
报告时间:2017年11月10日 10:00 (周五上午)
报告地点:生命科学学院534报告厅
 
报告人简介:杨贞标教授,国际知名植物学专家。1978-1982年, 华南热带作物学院植物保护系,1984-1986年,在美国爱荷华州立大学就读获硕士学位,1986-1990年就读于美国弗吉尼亚理工学院和州立大学获博士学位,1990-1993年在美国马里兰大学做博士后研究。1999-至今, 美国加州大学河滨分校植物系助理教授、副教授和教授。2004-至今,分别在中国农业大学,中科院上海植物生理生态研究所及福建农林大学担任教授,研究员及园艺中心主任,并荣获国家教育部“长江学者”、中央“千人计划”特聘专家等称号。先后承担了国家973,863和自然科学基因委、中国科学院、上海市等多项重大研究任务,在Science、Cell、Nature Communication、Current Biology、PNAS、Journal Cell Bio、Plant Cell等顶级期刊发表一百多篇重要研究成果,被引次数近12000。现任多家科学杂志期刊如Plant Physiology,Mol. Plant,Small GTPase,J. Int. Plant Biol.,Plant Cell and Physiology等编委。主要研究方向为:以模式植物拟南芥和水稻为研究对象,从事植物细胞极性生长分子与遗传机理、植物激素信号传导、植物细胞壁合成代谢等方向的研究。
 
报告内容简介:Tip growth is an extreme form of intrinsic self-organizing polar growth that generates tubular cells, while its growth axis is controlled by external vectorial cues such as gradients of attractants in growth guidance.  Such growth behavior allows tip-growing cells to efficiently explore the environment, invade host cells and target to the destination.  Both externally directed and intrinsic tip growth depend on polarized Rho GTPase signaling and exocytosis, suggesting a potential common design principle underlying these processes.  Using Arabidopsis pollen tubes as a model system, we have uncovered this design principal by integrating mathematical modeling with experimental approaches. Our studies suggest that at the heart of the design principle for intrinsic tip growth is polar exocytosis, which couples the self-organizing ROP1 GTPase feedback loops with the cell wall mechanical properties that maintain the cylindrical cell shape while allowing the apical expansion under internal turgor pressure. We further show that this design principle can explain how pollen tubes can find their path toward the source of attractive signals inside the ovule during pollination.  I will discuss how this design principle could also be integrated with mechanical signals to regulate the penetrative growth of pollen tubes through solid female tissues.