HVEM TOMOGRAPHY OF BASAL BODIES IN MUTANT AND WILD TYPE CHLAMYDOMONAS

突变型和野生型衣藻基底体的 HVEM 断层扫描

• 批准号: 7722828
• 负责人: SUSAN K DUTCHER
• 金额: $ 1.84万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7722828
• 关键词: Affect; Algae; Alleles; Biological Models; Cells; Centrioles; Chlamydomonas; Chlamydomonas reinhardtii; Computer Retrieval of Information on Scientific Projects Database; Data; Defect; Distal; Fiber; Flagella; Funding; Genes; Grant; Institution; Methods; Microtubules; Morphogenesis; Mutation; Positioning Attribute; Preparation; Protein Isoforms; Publishing; Research; Research Personnel; Resources; Role; Source; Specimen; Structure; Tubulin; United States National Institutes of Health; Work; alpha Tubulin; cell type; electron tomography; improved; kinetosome; mutant; novel; reconstruction; tomography

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Little is known about the assembly of basal bodies and centrioles. We are using Chlamydomonas as a model system to identify and characterize the molecules important for basal body structure and function. Over the past year, we have used improved methods of specimen preparation and dual-axis electron tomography to study the structure and organization of basal bodies in the unicellular alga, Chlamydomonas reinhardtii. This work has revealed novel structures in wild-type and in strains with mutations affecting specific tubulin isoforms. Tomographic reconstructions of basal bodies from the delta-tubulin deletion mutant, uni3-1, have confirmed that basal bodies contain mostly doublet microtubules. Moreover, the stellate fibers that are present only in the transition zone of wild-type cells repeat within the core of uni3-1 basal bodies. The distal striated fiber is incomplete in this mutant, rootlet microtubules can be misplaced, and multiflagellate cells have been observed. A suppressor of uni3-1, designated tua2-6, contains a mutation in alpha-tubulin. In combination with the delta-tubulin deletion tua2-6; uni3-1 cells build both flagella, yet they retain defects in basal body structure and rootlet microtubule positioning. These data suggest that the presence of specific tubulin isoforms directly affects the assembly and function of basal bodies and associated structures in Chlamydomonas. This work has been published (O'Toole et al., Mol. Biol. Cell 14: 2999-3012, 2003). We are now pursuing analysis of strains that have mutations in the BALD2 gene and a new gene, TNS1 that is important in basal body assembly. The Dutcher lab has recently found that the BALD2 gene encodes epsilon-tubulin. To further understand the role of BALD2 in basal body morphogenesis, we are analyzing strains with new bald2 alleles as well as extragenic suppressors that partially restore basal body structure and function.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 关于基础体和中心元素的组装知之甚少。 我们使用衣原体作为模型系统来识别和表征对基底体结构和功能重要的分子。在过去的一年中，我们使用了改进的标本制备方法和双轴电子断层扫描方法来研究单细胞藻类，Chlamydomonas Reinhardtii中基体的结构和组织。这项工作揭示了野生型和具有影响特定微管蛋白同工型的突变的菌株中的新结构。从三角肌缺失突变体UNI3-1的基础体的层析成像重建已经证实，基体主要含有双重小管。此外，仅在野生型细胞的过渡带中存在的星状纤维在Uni3-1基体核心内重复出现。在该突变体中，远端横纹纤维不完整，rootlet微管可能放错位置，并且已经观察到多粉状细胞。 指定为TUA2-6的Uni3-1的抑制剂包含α-微管蛋白的突变。结合三角微管蛋白缺失TUA2-6； Uni3-1细胞两者都会构建鞭毛，但它们将缺陷保留在基底体结构和root小管定位中。这些数据表明，特定微管蛋白同工型的存在直接影响衣原体中基体和相关结构的组装和功能。这项工作已经发表（O'Toole等，Mol。Biol。Cell。14：2999-3012，2003）。 现在，我们正在对BALD2基因中具有突变的菌株和一个新的基因TNS1进行分析，该菌株在基底体组装中很重要。荷兰实验室最近发现，BALD2基因编码Epsilon-Pubulin。为了进一步了解BALD2在基础体形态发生中的作用，我们正在用新的BALD2等位基因以及部分恢复基底体结构和功能的新bald2等位基因以及外部抑制器进行分析。