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

植物经常通过各种机制招募土壤微生物以提高养分的有效性和吸收。固氮（NF）共生和丛枝菌根（AM）共生是两个重要的例子。NF共生对能形成这种关系的作物如大豆、菜豆、豌豆、花生、苜蓿等具有重要的生长效应，而AM共生可以对形成这种共生的许多作物如玉米和水稻做同样的事情。特别是水稻（Oryza sativa），接种菌根真菌后，由于营养吸收的增强，可以显著提高产量。这在世界上依赖这种特定作物提供大部分卡路里的地区尤为重要。该奖项支持通过定义水稻SYP 132 A突变体的菌根表型来研究SYP 132 A基因在水稻（Oryza sativa）中的作用的研究。该研究最终将揭示水稻中的一个基本过程（AM共生），如果优化，该过程有可能大大提高产量。这项研究将与中国上海植物生理生态研究所的水稻AM共生专家王尔涛博士合作进行。植物固氮（NF）共生途径是从丛枝菌根（AM）共生途径演化而来的，因此其分子机制具有许多共同点。蛋白质运输从植物到细菌在NF共生已被证明是必不可少的，但蛋白质运输在AM共生是最重要的。在这个项目中，我将研究syntaxin基因（SYP 132 A）在菌根共生中的作用。该基因先前被鉴定为在M. truncatula，即它特异性地标记细胞内细菌周围的膜，用于靶向蛋白质递送。我将通过对水稻T-DNA突变体的菌根表型的分析来研究SYP 132 A的功能。我的假设是，这种蛋白质标志着植物细胞内将宿主与真菌分开的膜。这项研究将提供证据表明SYP 132 A的功能是通用的，并跨越多个宿主和微生物物种。该NSF EAPSI奖支持美国研究生的研究，并与中国科技部合作资助。

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.