Sex Determination in the Homosporous Fern Ceratopteris richardii

蕨Ceratipteris richardii的配子体 雌雄同体或雄性。 在这个过程中，主要的性别决定信号 和许多其他蕨类植物是一种类似赤霉素的信息素 是由配子体分泌的。 在它面前，一个少年 配子体发育为雄性，而在它的缺席， 幼鱼发育为一种两性辉石岩。 的主要目的 这项建议是使用基因和分子相结合的方法， 为了了解精子原如何控制配子体的性别 水蕨属 具体目标是：（1）确定关键 调节基因参与性别决定， 表征突变;和2）分离其表达 在对促精子剂的反应中， 筛选，其鉴定两种细胞之间丰度不同的mRNA， 通过消减杂交方法检测mRNA群体; 其表达的时间和空间模式， 通过表达他们的意见，评估他们的作用， 转基因植物中的反义cDNA。 %%% 对水翅目昆虫性别决定过程的分析， 推进我们对类似过程的一般理解， 植物，并将涉及更一般的问题， 生殖发育基因的激素控制 所有有机体。

Gametophytes of the fern ceratipteris 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 gametophyte. In its presence, a juvenile gametophyte develops as a male, whereas in its absence, the juvenile develops as a hermaphoxlite. The primary objective of this proposal is to use a combined genetic and molecular approach to understand how antheridiogen governs the sex of the gametophyte of Ceratopteris. The specific objectives are 1) to identify key regulatory genes involved in sex determination by generating and characterizing mutations; and 2) to isolate genes whose expression is altered in response to antheridiogen using a gene expression screen which identifies mRNAs that differ in abundance between two mRNA populations by a subtractive hybridization method; the temporal and spatial patterns of their expression will then be assessed and their function investigated by expressing their antisense cDNA in transgenic plants. %%% This analysis of the sex determining process in Ceratopterts may advance our general understanding of similar processes in higher plants, and will also relate to more general questions concerning hormonal control of genes involved in the reproductive development of all organisms.