Analysis of Vascular Pattern Formation in Leaves of Arabidopsis

[01:03 . 37]本文将利用分子遗传学方法分析拟南芥叶片维管模式形成的组成部分。叶片维管束模式的形成对发育的影响超出了叶脉的简单定位。叶原基中的前维管位点是静脉细胞形成的前体，似乎作为形态发生中心，调节维管细胞和其他叶细胞类型的定位和特化。这在功能上是有意义的，因为许多细胞类型必须与静脉合作，需要明确的空间关系。利用正向和反向遗传方法，已经确定了这一过程的潜在组成部分，包括血管前信号通路的可能成员。他们的角色将被分析，其他候选人将被描述。这些目标是：1)确定VH1血管前受体样激酶的直接信号通路伙伴，这是一个在组织血管区域中起关键作用的候选分子。2)确定cvp1甾醇甲基转移酶（SMT2）在血管前细胞定位或分化中的作用。这些过程在cvp1突变体中是缺陷的。3)确定以粗静脉突变体为代表的SAUR基因的作用。这可能代表生长素信号和静脉形成之间的直接联系。4)研究静脉模式缺陷突变体所鉴定的其他基因在静脉模式中的作用。

0110370NelsonThe components of leaf vascular pattern formation will be analyzed, using a molecular genetic approach in Arabidopsis. The formation of the leaf vascular pattern has developmental consequences beyond the simple siting of veins. Provascular sites in the leaf primordium, where the precursors of vein cells are formed, appear to serve as morphogenetic centers that regulate the location and specialization of vascular and other leaf cell types. This makes functional sense, since many of the cell types must function in cooperation with the veins, requiring a defined spatial relationship. Using forward and reverse genetic approaches, potential components of this process have been identified, including likely members of provascular signaling pathways. Their roles will be analyzed and additional candidates will be characterized. These are the aims:1) To identify the immediate signaling pathway partners of the VH1 provascular receptor-like kinase, which is a candidate for a key role in organizing vascular regions. 2) To determine the role of the cvp1 sterol methyl transferase (SMT2) in provascular cell siting or differentiation. These processes are defective in cvp1 mutants. 3) To determine the role of the SAUR gene represented by the thick vein mutant. This may represent a direct link between auxin signals and vein formation.4) To characterize the vein patterning roles of additional genes identified by mutants with vein pattern defects.