O'Neill E M, Rebay I, Tjian R, Rubin G M
Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley 94720-3200.
Cell. 1994 Jul 15;78(1):137-47. doi: 10.1016/0092-8674(94)90580-0.
We show that the activities of two Ets-related transcription factors required for normal eye development in Drosophila, pointed and yan, are regulated by the Ras1/MAPK pathway. The pointed gene codes for two related proteins, and we show that one form is a constitutive activator of transcription, while the activity of the other form is stimulated by the Ras1/MAPK pathway. Mutation of the single consensus MAPK phosphorylation site in the second form abrogates this responsiveness. yan is a negative regulator of photoreceptor determination, and genetic data suggest that it acts as an antagonist of Ras1. We demonstrate that yan can repress transcription and that this repression activity is negatively regulated by the Ras1/MAPK signal, most likely through direct phosphorylation of yan by MAPK.
我们发现，果蝇正常眼睛发育所需的两个Ets相关转录因子pointed和yan的活性受Ras1/MAPK信号通路调控。pointed基因编码两种相关蛋白，我们发现其中一种形式是转录的组成型激活因子，而另一种形式的活性则受Ras1/MAPK信号通路刺激。第二种形式中单个共有MAPK磷酸化位点的突变消除了这种反应性。yan是光感受器决定的负调节因子，遗传数据表明它作为Ras1的拮抗剂发挥作用。我们证明yan可以抑制转录，并且这种抑制活性受Ras1/MAPK信号负调控，最有可能是通过MAPK对yan的直接磷酸化作用。
