GENETICS OF AGAMOUS ACTION IN ARABIDOPSIS

拟南芥无性行为的遗传学

• 批准号: 2841048
• 负责人: ELLIOT M MEYEROWITZ
• 金额: $ 50.43万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2841048
• 关键词: Arabidopsis; cell cell interaction; cell type; chromosome walking; developmental genetics; gene expression; gene interaction; gene targeting; histogenesis; immunoelectron microscopy; in situ hybridization; leaf; molecular cloning; plant genetics; plant growth /development; plant morphology; polymerase chain reaction; regulatory gene; reporter genes; tissue mosaicism

The long-term objective of the proposed experiments is to understand the genetic and molecular mechanisms of pattern formation in multicellular organisms. The organism chosen for laboratory experiments is the flowering plant Arabidopsis thaliana, and the patterns to be studied are the patterns of organ identity and differentiated cell type in flowers. The choice of flowers and of Arabidopsis is for experimental convenience and speed: the plant is small, grows quickly, has powerful genetics, and is well-suited for facile molecular cloning and transformation. Flowers are to be used because they are highly patterned and demonstrate the key features of developmental pattern formation in all organisms, yet contain very few cell types, develop rapidly, and are inessential for plant viability. Mutants with abnormal flowers can therefore be easily obtained, grown, and studied. The health relevance of causal analyses of pattern formation is to birth defects, in which patterns have formed incorrectly; to inherited developmental disorders, in which regulatory genes such as those emphasized in this proposal act aberrantly; and to tumors, which consist of cells that have escaped normal negative controls on cell division, cellular differentiation, and cellular migration. The specific experiments proposed are to understand the regulation and activities of the floral organ-identity and regulatory gene AGAMOUS. AGAMOUS plays three key roles in floral pattern formation: it is necessary for specifying the stamens and carpels, it is necessary and sufficient to negatively regulate the genes that specify sepals and petals, and it is required for appropriate cell division patterns in the center of developing flower primordia. The protein product of the AGAMOUS gene is a DNA-binding transcriptional activator that is related at the level of amino acid sequence to human transcriptional regulators such as serum response factor, which regulates the c-fos oncogene, and MEF-2, which regulates muscle development. Three sets of experiments are proposed. The first are to understand the spatially-specific expression of AGAMOUS. This is in large part explained by two negative regulators of AGAMOUS that have been found. The genes encoding these negative regulators will be studied and cloned. Second, the activity of AGAMOUS in specifying organ identity will be studied. New methods have been developed and will be applied to finding the downstream genes activated by the A GA MO US gene product. Finally, the role of cell-cell communication in developing flowers will be studied by making genetic mosaics, again using new methods that have been devised for this type of experiment.

拟议实验的长期目标是了解 多细胞模式形成的遗传和分子机制 有机体。选择进行实验室实验的生物体是 开花植物拟南芥，拟研究的模式为 花的器官特征和分化细胞类型的模式。 选择花朵和拟南芥是为了实验方便。 和速度：植株小，生长快，有强大的遗传学， 非常适合于简单的分子克隆和转化。鲜花 将被使用，因为它们被高度图案化，并展示了关键 所有生物体的发育模式形成的特征，但包含 极少的细胞类型，发育迅速，对植物来说是不必要的 生存能力。因此，具有异常花朵的突变体很容易 获得、成长和研究的。原因分析与健康的相关性 模式形成与先天缺陷有关，在先天缺陷中已经形成了模式 不正确；遗传性发育障碍，在这种情况下， 像这项建议中强调的那些基因会产生反常的行为； 肿瘤，由逃脱正常阴性对照的细胞组成 关于细胞分裂、细胞分化和细胞迁移。 提出的具体实验是为了了解规则和 花器官识别和调控基因AGAMOUS的活性。 AGAMOUS在花卉图案的形成中扮演着三个关键角色：它是 为了指定雄蕊和心皮，它是必需的，并且 足以负向调节指定花冠和花冠的基因 花瓣，这是适当的细胞分裂模式所必需的。 花原基发育中心。AGAMOUS的蛋白质产物 基因是一种DNA结合的转录激活因子，与 氨基酸序列对人类转录调节因子的水平，如 调节c-fos癌基因的血清反应因子和MEF-2， 它调节肌肉的发育。三套实验是 建议。第一个是理解特定于空间的表达式 阿加莫斯的。这在很大程度上是由两个负面的监管机构解释的 已经发现的AGAMOUS。编码这些负值的基因 监管机构将被研究和克隆。第二，AGAMOUS的活动 在指定器官身份方面将进行研究。已经有了新的方法 开发并将应用于寻找激活的下游基因 由A GA MO US基因产品。最后，细胞的作用--细胞 花朵发育过程中的交流将通过使基因 马赛克，同样使用为这种类型的 做实验。