NSF/Alfred P. Sloan Foundation Postdoctoral Research Fellowship in Molecular Evolution for FY 1998

Bonnie C. McCaig本行动资助了1998年NSF/Alfred P. Sloan分子进化博士后研究奖学金。这些奖学金支持涉及生物进化变化和适应框架内分子水平生物模式和过程的理论、比较、计算和/或实验分析的研究。这些研究还包括利用分子数据来解决更广泛的进化问题。每个奖学金支持在赞助实验室进行的研究和培训计划。该奖学金的研究和培训计划题为“植物结构成分的进化”。针叶树中的木质素是由一个前体聚合产生的，而开花植物中的木质素是由两个前体聚合产生的。要解决的问题是第二个漆酶基因家族是否与被子植物中紫丁香木质素的起源相吻合？这两类木质素聚合漆酶对底物的偏好不同，这两类酶在植物发育过程中可能表达不同。本项目研究了编码漆酶（催化木质素聚合的酶）的基因的分子进化，以确定是否有一个单独的生物合成途径进化以提供被子植物木质素的丁香基成分。基因系统发育和表达研究用于确定在植物进化过程中，这些类别是否与木质素和细胞组成的变化平行分化。

Abstract DBI-9803949 Bonnie C. McCaig This action funds an NSF/Alfred P. Sloan Postdoctoral Research Fellowship in Molecular Evolution for 1998. These fellowships support studies involving the theoretical, comparative, computational, and/or experimental analyses of biological patterns and processes at the molecular level within the framework of organismic evolutionary change and adaptation. These studies also include the use of molecular data to address broader evolutionary questions. Each fellowship supports a research and training plan to be carried out in a sponsoring laboratory. The research and training plan for this fellowship is entitled evolution of structural components of plants. The lignin in conifers arises from the polymerization of one precursor, whereas that in flowering plants arises from two. The question being addressed is did a second laccase gene family coincide with the origin of syringyl lignin in angiosperms? The two classes of lignin-polymerizing laccases have different substrate preferences, and these classes may be expressed differentially during plant development. This project examines the molecular evolution of genes encoding laccases, the enzymes catalyzing lignin polymerization, to determine whether a separate biosynthetic pathway evolved to supply the syringyl component of angiosperm lignin. Gene phylogenies and expression studies are used to determine whether the classes diverged in parallel with changes in lignin and cell composition during plant evolution.