Ferguson B, Horecka J, Printen J, Schultz J, Stevenson B J, Sprague G F
Institute of Molecular Biology, University of Oregon, Eugene 97403-1229.
Cell Mol Biol Res. 1994;40(3):223-8.
The yeast (Saccharomyces cerevisiae) pheromone response pathway is one of the best understood eukaryotic signal transduction pathways. Nonetheless, it is likely that components and regulators of the pathway remain to be identified. We have employed three approaches to learn about interactions among known pathway components and to identify new components. First, the two-hybrid system of Fields and Song revealed that STE5, a protein of unknown biochemical function, interacts with each member of the MAP kinase cascade. One interpretation of this finding is that STE5 facilitates interactions between members of the cascade and thereby makes signal transmission more efficient. Second, genetic studies have identified new gene functions that appear to be involved in pheromone response. One of these is homologous to RHO-GAP proteins, an observation that suggests that a RHO protein (members of the RAS super-family) is part of the response pathway. A second gene function, FAR3, appears to be required only for a specific facet of pheromone response, arrest of the mitotic cell division cycle in G1.
酵母（酿酒酵母）的信息素应答途径是目前了解最为透彻的真核信号转导途径之一。尽管如此，该途径的组成成分和调控因子可能仍有待发现。我们采用了三种方法来研究已知途径成分之间的相互作用，并识别新的成分。首先，菲尔德斯和宋的双杂交系统表明，生化功能未知的蛋白质STE5与丝裂原活化蛋白激酶（MAPK）级联反应的每个成员相互作用。对这一发现的一种解释是，STE5促进了级联反应成员之间的相互作用，从而使信号传递更加高效。其次，遗传学研究确定了一些似乎参与信息素应答的新基因功能。其中之一与RHO-GAP蛋白同源，这一观察结果表明，一种RHO蛋白（RAS超家族成员）是应答途径的一部分。第二个基因功能FAR3似乎仅在信息素应答的一个特定方面是必需的，即在G1期阻止有丝分裂细胞分裂周期。
