Section of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.
Curr Biol. 2009 Sep 15;19(17):1447-52. doi: 10.1016/j.cub.2009.06.063. Epub 2009 Jul 30.
In Drosophila melanogaster, fruitless (fru) encodes male-specific transcription factors (FRU(M); encoded by fru P1) required for courtship behaviors (reviewed in). However, downstream effectors of FRU(M) throughout development are largely unknown. During metamorphosis the nervous system is remodeled for adult function, the timing of which is coordinated by the steroid hormone 20-hydroxyecdysone (ecdysone) through the ecdysone receptor, a heterodimer of the nuclear receptors EcR (isoforms are EcR-A, EcR-B1, or EcR-B2) and Ultraspiracle (USP) (reviewed in). Here, we show that genes identified as regulated downstream of FRU(M) during metamorphosis are significantly overrepresented with genes known to be regulated in response to ecdysone or EcR. FRU(M) and EcR isoforms are coexpressed in neurons in the CNS during metamorphosis in an isoform-specific manner. Reduction of EcR-A levels in fru P1-expressing neurons of males caused a significant increase in male-male courtship activity and significant reduction in size of two antennal lobe glomeruli. Additional genes were identified that are regulated downstream of EcR-A in fru P1-expressing neurons. Thus, EcR-A is required in fru P1-expressing neurons for wild-type male courtship behaviors and the establishment of male-specific neuronal architecture.
在黑腹果蝇中，fruitless（fru）编码雄性特异性转录因子（FRU（M）；由 fru P1 编码），这些转录因子对于求偶行为是必需的（综述于）。然而，FRU（M）在整个发育过程中的下游效应物在很大程度上是未知的。在变态期间，神经系统为成虫功能进行重塑，其时间由类固醇激素 20-羟基蜕皮酮（蜕皮酮）通过蜕皮激素受体协调，蜕皮激素受体是核受体 EcR（异构体为 EcR-A、EcR-B1 或 EcR-B2）和 Ultraspiracle（USP）的异二聚体（综述于）。在这里，我们表明，在变态过程中被鉴定为 FRU（M）下游受调控的基因，与已知对蜕皮酮或 EcR 有反应的基因显著重叠。FRU（M）和 EcR 异构体以特定异构体的方式在 CNS 中的神经元中在变态期间共同表达。在雄性中 fru P1 表达神经元中 EcR-A 水平的降低导致雄性间求偶活动显著增加，两个触角叶神经节体积显著减小。还鉴定了其他受 fru P1 表达神经元中 EcR-A 调控的基因。因此，EcR-A 在 fru P1 表达神经元中对于野生型雄性求偶行为和雄性特异性神经元结构的建立是必需的。
