Molecular Basis of Self-Incompatibility in Petunia

矮牵牛自交不亲和性的分子基础

• 批准号: 9603993
• 负责人: Teh-hui Kao
• 金额: $ 37.91万
• 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: 1997
• 资助国家: 美国
• 起止时间: 1997-05-01 至 2001-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9603993&HistoricalAwards=false
• 关键词: Molecular; Basis; Self; Incompatibility; Petunia

Teh-hui Kao 96-03993 Petunia inflata possesses gametophytic self-incompatibility which is controlled by a polymorphic locus, the S locus. Matching of S alleles carried by the pollen and pasta results In Inhibition of pollen tube growth in the style. The goal of this proposal is to understand how a pistil distinguishes between self and non-self pollen. Because so far only the products of pistil S alleles, S proteins or S RNases, have been identified, the first two objectives of this proposal are the identification of the pollen S gene and its allelic products. In the first objective, four approaches will be used to identify potential candidates for the pollen S gene: S protein affinity chromatography, the yeast two-hybrid protein-protein interaction assay, peptide display library screening, and mRNA differential display. cDNAs for the proteins peptides, and PCR fragments identified will be isolated and examined to determine whether their corresponding genes co-segregate with S alleles and show sequence variation between alleles, two criteria for the pollen S gene. The second objective is to use gain-of-function and loss-of-function approaches to ascertain whether any of those pollen genes that meet the above two criteria is the pollen S gene. The third objective is to use two approaches to ascertain whether allele specific inhibition of pollen lies in selective uptake of self S proteins into pollen tubes. The first approach is to examine whether production of a mutant S3 protein lacking RNase activity in the cytoplasm of S3 pollen of transgenic plants has a dominant negative effect on the self-incompatibility behavior of S3 pollen. The second approach is to examine whether S3 protein is taken up by S2 (non-self) and/or S3 (self) pollen tubes by immunolocalization of microscopic sections of pollen tubes that grow out of cut ends of S3S3 pistils that have been pollinated with S2 and S3 pollen, separately. The use of RNases as recognition molecules is unique to the type of self-incompatibility studied here, thus this proposed research when completed will uncover a new paradigm for cellular recognition in biological systems and expand the scope of the understanding of the biological functions of RNases. On the practical side, once the pollen S gene is identified, one can explore the possibility of restoring the self-incompatibility trait to self-compatible cultivated species to facilitate hybrid seed production. If successful, this will have a very important impact on agriculture.

teh-hui Kao 96-03993 petunia forta具有配子植物的自我不相容性，由多态性基因座（s）控制。花粉和意大利面带来的S等位基因的匹配导致抑制样式的花粉管生长。该提案的目的是了解雌蕊如何区分自我和非自我花粉。 由于迄今为止仅确定了雌蕊等位基因，S蛋白或S RNase的产物，因此该提案的前两个目标是鉴定花粉基因及其等位基因产品。在第一个目标中，将使用四种方法来识别花粉基因的潜在候选：S蛋白亲和色谱，酵母两杂化蛋白 - 蛋白质 - 蛋白质相互作用测定，肽显示库筛选和mRNA差异显示。将分离并检查蛋白质肽和PCR片段的cDNA，以确定其相应的基因是否与S等位基因共隔离并显示等位基因之间的序列变化，这是花粉基因的两个标准。第二个目标是利用功能获得和功能丧失方法来确定符合上述两个标准的花粉基因中的任何一个是花粉基因。第三个目标是使用两种方法来确定等位基因对花粉的特异性抑制是否在于选择性摄取自蛋白进入花粉管。第一种方法是检查转基因植物S3花粉中缺乏RNase活性的突变体S3蛋白的产生是否对S3花粉的自我不相容性行为具有显着的负面影响。第二种方法是检查S3蛋白是否通过S2（非自我）和/或S3（自我）花粉管吸收，通过对花粉管的微观切片的免疫定位，这些小花粉管从分别授粉S2和S3粉的S3S3雌性的切割末端生长出来。 在这里研究的自我兼容性的类型是，将RNase用作识别分子是独有的，因此，完成后的研究将发现生物系统中细胞识别的新范式，并扩展了对RNass生物学功能的理解的范围。在实用方面，一旦鉴定出花粉基因，就可以探索将自我不相容性特征恢复到自兼容培养物种以促进杂交种子生产的可能性。如果成功，这将对农业产生非常重要的影响。