A Molecular Role for Plant LINC complexes in Pollen Tube and Guard Cell Function.

本项目探索了一类新的植物蛋白的功能，这些蛋白位于植物细胞中细胞核的外围-遗传信息的中心。这些神秘的蛋白质复合物将细胞核内部与细胞质（细胞核周围的细胞部分）连接起来，对植物的许多功能都很重要。这个项目将探索两个功能。首先，它们在花粉管中的作用，花粉管对开花植物的受精和种子生产（粮食产量）至关重要。第二种是保护细胞，这些细胞控制植物叶片气孔（气孔）的打开和关闭，气孔调节二氧化碳从空气中进入植物的运动，以及植物叶片向空气中水分的损失（以蒸汽的形式）。面对日益频繁的气候事件，如干旱、极端温度和地球大气中二氧化碳含量的上升，从空气中吸收二氧化碳和从植物中流失水分的作用更加重要。除了培养细胞和分子生物学方面的博士后科学家、研究生和本科生外，该项目还将发起和发展一个涉及艺术的外展项目，将研究的各个方面可视化，并向更广泛的公众展示。植物特异性外核包膜蛋白（KASH蛋白）是核骨架和细胞骨架（LINC）复合物连接体的功能等效的动物KASH蛋白。本项目将剖析KASH蛋白在植物雄性生殖和保护细胞孔径调节中的作用。一个植物特有的LINC复合体需要使营养核通过花粉管，它的破坏影响花粉管的终止和雄性的育性。这个新发现的过程与花粉管功能的已知信号通路（包括ROS和钙信号）的联系将被确定；数学模型将用于模拟营养核的运动和突变引起的缺陷；以及与LINC复合物相互作用并参与运动的运动蛋白。第二种植物特异性LINC复合物位于保护细胞的细胞核中，它的破坏改变了保护细胞的非生物胁迫反应和保护细胞动力学。该LINC复合物、保护细胞皮层肌动蛋白模式、核钙信号和液泡形态之间的联系将被剖析。此外，植物膜的候选蛋白将被测试与植物LINC复合物的相互作用，以及它们在上述保护细胞和花粉管生物学中的作用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project explores the function of a new class of plant proteins that are located at the periphery of the nucleus - the center of genetic information - in the plant cell. These enigmatic protein complexes connect the inside of the nucleus to the cytoplasm - the part of the cell that surrounds the nucleus - and are important for a number of plant functions. This project will explore two functions. First, their role in pollen tubes, which are essential for fertilization and seed production (grain yield) in flowering plants. And second, guard cells, the cells that control the opening and closing of apertures (stomata) in the leaf of the plant, which regulate the movement of carbon dioxide from the air into the plant, and the loss of water (as vapor) from plant leaves into the air. The uptake of carbon dioxide from the air and the loss of water from the plant are of added significance in the face of increasingly frequent climate events such as drought, temperature extremes and the rising levels of carbon dioxide in the earth's atmosphere. In addition to training postdoctoral scientists, and graduate and undergraduate students, in cell and molecular biology, the project will initiate and develop an outreach project involving art to visualize aspects of the research and present them to the broader public.Plant-specific outer nuclear envelope proteins (KASH proteins) are the functional equivalent of animal KASH proteins of the linker of nucleoskeleton and cytoskeleton (LINC) complexes. This project will dissect how KASH proteins function in plant male fertility and guard cell aperture regulation. One plant specific LINC complex is required to move the vegetative nucleus through the pollen tube and its disruption affects pollen tube termination and male fertility. The connection of this newly discovered process to known signaling pathways of pollen tube function, including ROS and calcium signaling, will be determined; mathematical modeling will be applied to simulate the movement of the vegetative nucleus and the defects caused by the mutants; and motor proteins will be identified that interact with the LINC complex and are involved in the movement. A second plant-specific LINC complex is located at the nucleus of guard cells and its disruption changes guard cell abiotic stress response, and guard cell dynamics. The connection between this LINC complex, guard cell cortical actin patterns, nuclear calcium signaling, and vacuolar morphology will be dissected. In addition, candidate proteins for a plant lamina will be tested for interactions with the plant LINC complexes and for their involvement in the guard cell and pollen tube biology described above.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.