Vascular Pattern Formation in Leaves of Arabidopsis

Timothy M. NelsonIOS-1021188叶中的维管模式形成本项目旨在了解原维管（PV）细胞和原形成层细胞（PC）文件的模式和活动，这是叶脉网络形成的连续阶段。生长素信号和生长素极性运输（PAT）的空间模式化作用最近已被证明在许多发育过程中，如叶片的启动和静脉的图案化。然而，生长素模式的每一种情况都依赖于不同的背景-某些细胞和其中的某些途径以该过程特有的方式，在发育的正确时间和地点产生生长素反应。也就是说，生长素作用的上游和下游都有特定的过程特征。该项目的先前结果表明，特定的甾醇调节叶脉图案的形成。该项目将使用遗传学，细胞生物学和生物化学来测试特定甾醇分子提供发育中叶组织的细胞空间信息与促进静脉模式的PAT机制之间的联系的假设。这些结果将揭示（1）PAT过程受特定甾醇分子的调节，（2）静脉形成区域中甾醇和甾醇结合蛋白基因的调节，以及（3）受特定甾醇影响的静脉图案形成基因的身份。 随着对静脉图案化和分化的理解的增加，它将提供影响发育、发病机制防御和生理学（例如，C4光合作用、资源分配、养分吸收、耐旱性等），所有这些都依赖于叶脉。该项目作为学生，博士后科学家和少数民族暑期研究实习生的培训工具。该项目是PI向非科学本科生教授生物学的插图来源，其中许多人对科学政策和科学社会问题感兴趣。

Timothy M. NelsonIOS-1021188Vascular pattern formation in leaves of ArabidopsisThis project seeks to understand the patterning and activities of provascular (PV) cells and procambial cell (PC) files, which are successive stages in the formation of leaf vein networks. A spatial patterning role for auxin signaling and polar auxin transport (PAT) has been demonstrated recently in many developmental processes, such as the initiation of leaves and the patterning of veins. However, each case of auxin patterning relies on a distinct context - certain cells and certain pathways within them are made auxin-responsive in a manner unique to that process, at the right time and place in development. That is, there are process-specific features both upstream and downstream of auxin's role. Prior results from this project suggest that specific sterols regulate pattern formation for leaf veins. This project will use genetics, cell biology and biochemistry to test the hypothesis that specific sterol molecules provide a connection between cellular spatial information in developing leaf tissue and the PAT machinery that facilitates vein patterns. The results would reveal (1) the regulation of the PAT process by specific sterol molecules, (2) the regulation of genes for sterols and sterol-binding proteins in vein-forming regions, and (3) the identity of vein patterning genes that are affected by specific sterols. As understanding of vein patterning and differentiation increases, it will provide a means of influencing development, pathogenesis defense, and physiology (e.g., C4 photosynthesis, resource allocation, nutrient uptake, drought tolerance, etc.), all of which depend on leaf veins. This project serves as a training vehicle for students, postdoctoral scientists, and minority summer research interns. The project is a source of illustrations for the PI's teaching of biology to non-science undergraduates, many of whom have interest in working on science policy and science & society issues.