The Genetic Basis of Sex Determination in The Homosporous Fern Ceratopteris Richardii

9405780银行本提案的主要目的是使用遗传方法来了解如何花药素和脱落酸管理的性别的配子体的水蕨属。 通过产生和表征改变正常性表型的突变，已经确定了至少一些参与性别决定的关键调控基因。 一个假设的模型，这些基因如何相互作用的监管层次已经提出。 拟议研究的一个目标是继续对这些突变体进行遗传、形态学基因和生理学分析，以了解这些基因的野生型功能，并进一步测试和修改拟议的基因相互作用模型。 水蕨的配子体是雌雄同体的或雄性的。 在这种蕨类植物和许多其他蕨类植物中，决定性别的主要信号是雄激素，一种类似赤霉素的信息素，由两性配子体分泌，促进其他性别未定的幼年配子体的雄性发育。 植物激素脱落酸阻断雄激素反应。 植物的性别是如何决定的是一个重要的发展问题，其答案最终在农业和植物育种中有实际应用。 拟议的研究将提供参与性别决定的基因的基本理解，也将有助于理解植物细胞如何协调以维持单一的性发育命运，以及生物体内细胞的性发育命运如何改变以适应环境的变化。 ***

9405780 Banks The primary objective of this proposal is to use a genetic approach to understand how antheridiogen and abscisic acid govern the sex of the gametophyte of Ceratopteris. At least some key regulatory genes involved in sex determination have been identified by generating and characterizing mutations that alter the normal sexual phenotype. A hypothetical model of how these genes interact in a regulatory hierarchy has been proposed. One objective of the proposed research is to continue with the genetic, morphological genes and physiological analysis of these mutants in order to understand the wild type functions of these genes and to further test and modify the proposed model of gene interaction. %%% Gametophytes of the fern Ceratopteris richardii are either hermaphroditic or male. The primary sex-determining signal in this and many other ferns is antheridiogen a gibberellin-like pheromone that is secreted by the hermaphroditic gametophyte and promotes male development of other sexually undetermined juvenile gametophytes. The plant hormone abscisic acid blocks the antheridiogen response. How sex is determined in plants is an important developmental question whose answer many ultimately have practical applications in agriculture and plant breeding. The proposed studies will provide a basic understanding of the genes involved in sex determination, and will also be of value in understanding how plant cells are coordinated to maintain a single sexual developmental fate, and how the sexual developmental fate of cells within an organism can change to adapt to changes in the environment. ***