CAREER: Molecular mechanisms of phloem transport and seed loading of heavy metals

植物和种子是蛋白质、维生素和微量营养素（如锌、铁和锰）的主要膳食来源。该项目的重点是了解分子是如何装载到种子中的，以此为基础，选择性地向主要种子作物添加特定的营养物质，如铁和锌，这一过程被称为生物强化。韧皮部是一种维管组织，将营养物质输送到植物的各个部位。营养物质通过韧皮部血管（静脉）进入种子，韧皮部血管穿过叶子和茎。在叶片中，分子通过位于同伴细胞中的转运蛋白被装载到韧皮部流中。尽管它们很重要，但大多数伴生细胞特异性转运蛋白仍不为人所知。该项目将使用一种强大的分子技术（核糖序列）来区分在伴侣细胞中表达的转运蛋白基因和在其他类型细胞中表达的转运蛋白基因。通过确定每个转运基因动员到韧皮部流中的分子类型（氨基酸、维生素、金属等），将进一步表征韧皮部装载转运基因。此外，该项目将通过开展三项主要的外展活动来整合跨学科的教育计划，这些活动将持续监测和评估，以最大限度地提高效益。首先，新闻系学生将有科学活动的实践经验，并将通过媒体报道、视频和博客交流他们的经验。科学新闻对于提高人们对科学如何影响社区的认识至关重要。第二，这个项目将把植物科学和工程专业的学生聚集在一起，让他们参与跨学科的研究。这些类型的相互作用极大地改善了人们对生物系统的理解方式，并将为未来的跨学科合作创造更多机会。第三，将邀请高中科学教师讨论当前植物生物学的研究，并将新的发展纳入他们现有的课程。

Plants and seeds are the main dietary source of proteins, vitamins and micronutrients such as zinc, iron and manganese. This project focuses on understanding how molecules are loaded into seeds as a basis to selectively enrich staple seed crops with specific nutrients such as iron and zinc, a process referred to as bio-fortification. Phloem is a vascular tissue that transports nutrients to all parts of the plant. Nutrients are loaded into seeds by phloem vessels (veins) that run across the leaves and through the stem. In leaves, molecules are loaded into the phloem stream by transporter proteins located in companion cells. Despite their importance, the majority of transporter proteins specific to companion cells remain unknown. This project will use a powerful molecular technique (ribo-seq) to differentiate between transporter genes expressed in companion cells and transporter genes expressed in other types of cells. Phloem-loading transporter genes will be further characterized by identifying the type of molecule (amino acids, vitamins, metals, etc) each transporter gene mobilizes into the phloem stream. Additionally, this project will integrate cross-disciplinary educational programs by pursuing three major outreach activities that will be continuously monitored and evaluated to maximize the benefits. First, journalism students will have hands-on experience on scientific activities and will communicate their experiences through media stories, videos and blogs. Scientific journalism is vital to promoting awareness about how science impacts communities. Second, this project will bring together plant science and engineering students by engaging them in interdisciplinary research. These types of interactions have dramatically improved the way biological systems are understood and will generate more opportunities for future interdisciplinary collaboration. Third, high school science teachers will be invited to discuss current research on plant biology and incorporate new developments into their existing curriculum.