Genetic Studies of ASK Gene Functions

ASK 基因功能的遗传学研究

• 批准号: 0092075
• 负责人: Hong Ma
• 金额: $ 39万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0092075&HistoricalAwards=false
• 关键词: Genetic; Studies; ASK; Gene; Functions

Plant development requires the coordinated activity of many gene products, which can be regulated at both the levels of protein synthesis and degradation. Many regulatory genes controlling flower development encode putative transcription factors, but few are known to regulate proteolysis. Work supported by an NSF grant indicates that the Arabidopsis ASK1 gene regulates vegetative and flower development and encodes a homolog of the yeast and human SKP1 protein. SKP1 is a subunit of SCF ubiquitin ligase complexes that catalyze the third step of a pathway that covalently links ubiquitins to target proteins, mediating the degradation of proteins. ASK1 interacts with UFO genetically to regulate flower development and the expression of the floral genes APETALA3 (AP3) and PISTILLATA (PI). The working model is that UFO and ASK1 are components of a SCF ubiquitin ligase that facilitates the degradation of a negative regulator of AP3 and PI expression. Furthermore, ASK1 is essential for homolog separation and segregation during male meiosis I. In meiosis I, specific proteins must be degraded at the metaphase/anaphase transition to allow the separation of homologs. Therefore, the simplest hypothesis is that ASK1 regulates such a proteolytic event. Arabidopsis possesses at least 20 SKP1 homologs, named ASKs. The functions of the other ASK genes are not known. The fact that the yeast SKP1 gene is essential for mitotic growth suggests that other ASK gene(s) probably have redundant functions that together control essential cellular processes. Therefore, understanding other ASK gene functions should provide new insights into the role of regulated proteolysis during development. In this project, the ASK1 function in regulating flower development will be further analyzed using genetic and molecular approaches, including the interaction between UFO and ASK1 in the context of regulation of AP3 and PI expression. In addition, the role of ASK1 in controlling homolog separation in meiosis I will be investigated using microscopic procedures. Moreover, additional ASK genes will be characterized by expression studies, by functional comparison with ASK1, and some of those ASK genes expressed in the flowers will be tested for function using reverse genetic approaches. These experiments will likely provide new insights about how plant reproductive development is regulated by genes, potentially benefiting agriculture and the environment. The study of gene functions when the Arabidopsis sequencing has is just been completed is both timely and beneficial. The results from these experiments will also likely provide the starting points for future research by many in the community of plant scientists as well as those studying non-plant organisms.

植物的发育需要许多基因产物的协调活性，这些活性可以在蛋白质合成和降解两个水平上进行调节。 许多控制花发育的调控基因编码假定的转录因子，但很少有人知道调节蛋白水解。 由NSF资助的工作表明，拟南芥ASK 1基因调节营养和花的发育，并编码酵母和人类SKP 1蛋白的同源物。 SKP 1是SCF泛素连接酶复合物的亚基，其催化将泛素共价连接至靶蛋白的途径的第三步，介导蛋白质的降解。ASK 1与UFO相互作用，调节花发育和花基因APETALA 3（AP 3）和PISTILLATA（PI）的表达。 工作模型是UFO和ASK 1是SCF泛素连接酶的组分，其促进AP 3和PI表达的负调节剂的降解。 此外，ASK 1在雄性减数分裂I期间对于同源物分离和分离是必需的。 在减数分裂I中，特定的蛋白质必须在中期/后期转换时降解，以允许同源物的分离。 因此，最简单的假设是ASK 1调节这样的蛋白水解事件。 拟南芥至少有20个SKP 1同源物，称为ASK。 其他ASK基因的功能尚不清楚。 酵母SKP 1基因对有丝分裂生长是必需的这一事实表明，其他ASK基因可能具有共同控制基本细胞过程的冗余功能。 因此，了解其他ASK基因的功能应该提供新的见解调节蛋白水解在发展过程中的作用。 在这个项目中，ASK 1在调控花发育中的功能将使用遗传和分子方法进行进一步分析，包括UFO和ASK 1在调控AP 3和PI表达的背景下的相互作用。此外，ASK 1在减数分裂I中控制同源物分离的作用将使用显微镜程序进行研究。 此外，额外的ASK基因将通过表达研究，通过与ASK 1的功能比较来表征，并且将使用反向遗传方法测试在花中表达的一些ASK基因的功能。 这些实验可能会为植物生殖发育如何受基因调控提供新的见解，可能有利于农业和环境。 在拟南芥测序刚刚完成的时候进行基因功能的研究是及时的，也是有益的。 这些实验的结果也可能为许多植物科学家以及研究非植物生物的人提供未来研究的起点。