EAPSI: Elucidating the Role of SYP132A during Arbuscular Mycorrhizal Symbiosis in Oryza Sativa

植物经常招募土壤微生物，以提高营养的有效性和吸收的各种机制。固氮（NF）共生和丛枝菌根（AM）共生是两个重要的例子。NF共生对形成这种共生关系的作物有主要的生长影响，如大豆、普通豆、豌豆、花生、苜蓿等，而AM共生对形成这种共生关系的许多作物也有同样的影响，如玉米和水稻。特别是水稻（Oryza sativa），接种菌根真菌可以显著提高产量，因为营养吸收增强。这在世界上依赖这种特殊作物获取大部分热量的部分地区尤为重要。该奖项支持通过定义水稻SYP132A突变体的菌根表型来研究SYP132A基因在水稻（Oryza sativa）中的作用。这项研究可能最终揭示水稻的一个基本过程（AM共生），如果优化，有可能大大提高产量。该研究将与中国上海植物生理与生态研究所的水稻AM共生专家王二涛博士合作进行。植物固氮（NF）共生途径是由丛枝菌根（AM）共生途径演变而来的，因此它们的分子机制有许多共同的要素。在NF共生过程中，从植物到细菌的蛋白质运输已被证明是必不可少的，但在AM共生过程中的蛋白质运输也很可能是最重要的。在这个项目中，我将研究syntaxin基因（SYP132A）在菌根共生中的作用。该基因先前被确定在M. truncatula的NF共生中起作用，即它特异性地标记胞内细菌周围的膜以靶向蛋白质递送。我将通过表征水稻T-DNA突变系的菌根表型来研究SYP132A的功能。我的假设是，这种蛋白质在植物细胞中标记了将寄主和真菌分开的膜。这项研究将证明SYP132A的功能是普遍的，并且跨越多种宿主和微生物物种。该奖项由美国国家科学基金会EAPSI与中国科技部合作资助，支持一名美国研究生的研究。

Plants often recruit soil microbes in order to enhance nutrient availability and absorption by an assortment of mechanisms. Nitrogen-fixing (NF) symbiosis and arbuscular mycorrhizal (AM) symbiosis are two important examples. NF symbiosis has major growth effects on the crops that can form this relationship such as soybean, common bean, pea, peanuts, alfalfa, etc., while AM symbiosis can do the same for many crops that form this symbiosis such as maize and rice. Rice (Oryza sativa), specifically, can have a significant grain yield increase when inoculated with mycorrhizal fungi because of the enhanced nutrient uptake. This can be especially important in parts of the world that rely on this particular crop for the majority of its calories. This award supports research to investigate the role of the SYP132A gene in rice (Oryza sativa) by defining the mycorrhizal phenotype of rice SYP132A mutants.The research could ultimately shed light on a fundamental process in rice (AM symbiosis) that has the potential to greatly increase yield if optimized. The research will be conducted in collaboration with Dr. Ertao Wang, an expert in AM symbiosis in rice, at the Institute of Plant Physiology and Ecology in Shanghai, China. The nitrogen-fixing (NF) symbiotic pathway in plants evolved from the arbuscular mycorrhizal (AM) symbiotic pathway, and therefore the molecular mechanisms share many common elements. Protein trafficking from the plant to the bacteria during NF symbiosis has been shown to be indispensable, but protein trafficking during AM symbiosis is most likely important as well. For this proposed project, I will study the role of a syntaxin gene (SYP132A) in mycorrhizal symbiosis. This gene was previously identified to have a role in NF symbiosis in M. truncatula, namely, it specifically marks the membrane surrounding the intracellular bacteria for targeted protein delivery. I will investigate the function of SYP132A by characterizing the mycorrhizal phenotype of rice T-DNA mutant lines. My hypothesis is that this protein marks the membrane that separates host from the fungus within plant cells. This study will provide evidence that the function of SYP132A is universal and spans multiple host and microbial species. This NSF EAPSI award supports the research of a U.S. graduate student and is funded in collaboration with the Chinese Ministry of Science and Technology.