Differential Expression of the Diverse Plant Actins

多种植物肌动蛋白的差异表达

• 批准号: 7931495
• 负责人: Richard Brian Meagher
• 金额: $ 6.7万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7931495
• 关键词: Actin-Binding Protein; Actins; Affect; Alleles; Animals; Arabidopsis; Back; CCL4 gene; Cell Nucleolus; Cell Nucleus; Cellular biology; Chromatin Remodeling Factor; Cues; Cytoplasm; Cytoskeletal Gene; Cytoskeleton; Defect; Development; Down-Regulation; Epigenetic Process; Equilibrium; Evolution; Experimental Designs; Family; Family Study; Flowers; Gene Expression; Gene Expression Regulation; Gene Family; Gene Proteins; Genes; Genetic; Grant; Human; Interphase; Investigation; Knock-out; Knowledge; Link; Modeling; Molecular Medicine; Molecular Profiling; Muscle; Mutation; Nuclear; Organ; Outcomes Research; Pattern; Phenotype; Plants; Play; Protein Family; Protein Isoforms; Proteins; Regulation; Relative (related person); Role; Staging; System; Testing; Tissues; Transcription factor genes; Trees; Vascular Plant; Vertebrates; Work; actin depolymerizing factor; base; chromatin remodeling; member; molecular phenotype; mutant; profilin; reproductive

DESCRIPTION (provided by applicant): We propose there are two classes of actin-based cytoskeletal systems, vegetative (VEG) and reproductive (REP), which have functioned and evolved with relative independence for more than 350 million years in vascular plants, similar to the cytoplasmic and muscle actin systems in vertebrates. To understand the relative importance of differences in gene regulation and protein isovariant sequence, we examined the gene families encoding eight actins (ACT), five profilins (PRF), eleven actin depolymerizing factors (ADF), and six nuclear actin-related proteins (ARP). The ACT, ADF, and PRF cytoskeletal families contained ancient subclasses of genes with VEG or REP expression patterns, while the ARPs were constitutively expressed. Knockout and knockdown alleles among the ACT, ADF, PRF, and ARP genes revealed numerous and diverse phenotypic defects in every stage of multicellular development. We constructed highly synthetic healthy plants with a single VEG actin isovariant to demonstrate the importance of VEG gene regulation. We were able to suppress ectopic REP actin gene expression with REP, but not VEG, ADFs and PRFs demonstrating the importance of isovariant-specific interactions. While ACT, ADF, and PRF defects resulted in alterations in the cytoskeleton, a few alleles shared epigenetic changes in transcription factor gene expression leading to altered development with ARP mutants. Because nuclear ARPs are known to function primarily in chromatin remodeling complexes containing conventional actin subunits, these results led to a new proposal: the transcriptional expression of master regulators of development is controlled by conventional actins functioning in chromatin remodeling complexes, with the level of actin in the nucleus controlled by ADFs and PRFs. Our Specific Aims in the next grant period are: 1) to characterize the phenotypes of ACT, ADF, and PRF mutants; 2) to characterize gene and isovariant specific interactions and their roles in multicellular development; and 3) to explore how the roles of these proteins are balanced between nuclear epigenetic and cytoplasmic cytoskeletal functions. Differences among protein isovariants and their differential regulation are now widely recognized to play an essential role in animal multicellular development. Undoubtedly, our experimental designs and research outcomes outline a path for such studies in molecular medicine (e.g., human nemaline actin mutations).

描述（由申请人提供）：我们建议有两类基于肌动蛋白的细胞骨架系统，营养（VEG）和生殖（REP），它们在血管植物中具有相对独立性的作用和进化超过3.5亿年，与脊椎动物中的细胞质和肌肉肌动蛋白系统相似。为了了解基因调节和蛋白质等异分序列差异的相对重要性，我们检查了编码八种肌动蛋白（ACT），五个叶酸蛋白（PRF），11个肌动蛋白解聚因子（ADF）和六个核肌动蛋白相关蛋白（ARP）的基因家族。该ACT，ADF和PRF细胞骨架家族包含具有蔬菜或REP表达模式的基因的古代子类，而ARP则是组成型表达的。该ACT，ADF，PRF和ARP基因中的敲除和敲除等位基因在多细胞发育的每个阶段都显示出许多不同的表型缺陷。我们用单个蔬菜肌动蛋白异源构建了高度合成的健康植物，以证明VEG基因调节的重要性。我们能够用REP，veg，ADF和PRF抑制异位REP肌动蛋白基因表达，证明了异源特异性相互作用的重要性。尽管ACT，ADF和PRF缺陷导致细胞骨架的改变，但一些等位基因在转录因子基因表达中共有表观遗传变化，从而导致ARP突变体的发育改变。由于已知核ARP主要在含有常规肌动蛋白亚基的染色质重塑络合物中起作用，因此这些结果导致了一个新的建议：发育主调节剂的转录表达受染色质重塑复合物中的常规肌动蛋白的控制，并由ADFS和PRFS和PRFS控制的肌动蛋白水平控制肌动蛋白水平。我们在下一个赠款期间的具体目标是：1）表征行为，ADF和PRF突变体的表型； 2）表征基因和异源特定相互作用及其在多细胞发育中的作用； 3）探索这些蛋白质的作用如何在核表观遗传和细胞质细胞骨架功能之间保持平衡。现在，蛋白质等异源及其差异调节的差异已被广泛认可在动物多细胞发育中起着至关重要的作用。毫无疑问，我们的实验设计和研究成果概述了这种分子医学研究的途径（例如人类羟基肌动蛋白突变）。