DIFFERENTIAL EXPRESSION OF THE DIVERSE PLANT ACTIN GENES

高等植物含有肌动蛋白基因家族，该家族由许多古老的和 不同的班级。有人认为，古代植物肌动蛋白的类别 基因在维管束植物进化过程中一直被保存下来，因为它们 具有独特的基因调控模式和/或编码肌动蛋白 独一无二的功能。这项研究的一个主要目标是定义 这些类别在细胞、组织和组织中的差异表达 器官类型和发育。的初始物理特征 拟南芥中的几个肌动蛋白基因和不同的蛋白质异构体表明 它是追求这一目标的理想工厂，结果将是 大多数被子植物的代表。其中一组目标侧重于 描述不同基因家族的表达模式 拟南芥中的成员。为了实现这一点，一种mRNA表型将是 根据不同的细胞类型和组织确定，从 根部。聚合酶链式反应(PCR)介导的转录本测序 来自单一细胞类型或组织的基因将明确定义 表型。将使用内部控制来量化表达。一个 第二个目标是定义肌动蛋白在不同细胞和 在组织和植物发育过程中。具体目标包括制定两个 肌动蛋白突变体的类型。肌动蛋白T-DNA插入杂合子植物 将从大量T-DNA插入突变体中分离出基因 使用聚合酶链式反应筛查方法。另一种方法是使用马赛克 植物肌动蛋白突变体，以保持亲本生物体的生存能力。一个 休眠指示剂β-葡萄糖醛酸苷酶基因与反义肌动蛋白的融合 RNA将通过失去转录本中的DS转座子而被激活 领袖。这种方法还有一个额外的优点，那就是表达 发育模式中的突变表型。植物、器官和细胞 显示突变表型或表达GUS的谱系将被鉴定 细胞化学和生物化学研究肌动蛋白的表达。一个终极目标是 肌动蛋白基因家族成员的多样性与 维管束植物细胞类型和组织的起源 植物肌动蛋白的功能建议。

Higher plants contain a family of actin genes made up of many ancient and diverse classes. It is proposed that the ancient classes of plant actin genes have been preserved throughout vascular plant evolution because they have unique patterns of gene regulation and/or encode actin proteins with unique functions. A major goal of this research is to define the differential expression of these classes with respect to cell, tissue and organ type, and development. An initial physical characterization of several actin genes and diverse protein isovariants in Arabidopsis suggests it is the ideal plant in which to pursue this goal and that results will be representative of most angiosperms. One set of objectives focuses on delineating the patterns of expression for the different gene family members in Arabidopsis. To accomplish this an mRNA phenotype will be determined for variety of cell types and tissues beginning with those in root. Polymerase chain reaction (PCR) mediated sequencing of transcripts from a single cell type or tissue will unambiguously define the mRNA phenotypes. Internal controls will be used to quantify expression. A second goal focus on defining the roles for actins in different cells and tissues and in plant development. Specific objectives include making two types of actin mutants. Plants heterozygous for T-DNA insertions in actin genes will be isolated from a large population of T-DNA insertion mutants using a PCR screening method. An alternative approach makes use of mosaic plant actin mutants to preserve the viability of the parent organism. A dormant indicator beta-glucuronidase (GUS) gene fused to an antisense actin RNA will be activated by the loss of a Ds transposon in the transcript leader. This approach has the additional advantage of expressing the mutant phenotype in a developmental pattern. Plants, organs and cell lineages showing mutant phenotype or expressing GUS will be characterized cytochemically and biochemically for actin expression. An ultimate goal is to correlate the diversification of actin gene family members with the origin of cell types and tissues in vascular plants and with the numerous functions proposed for plant actins.