Soller Matthias, Haussmann Irmgard U, Hollmann Martin, Choffat Yves, White Kalpana, Kubli Eric, Schäfer Mireille A
Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454, USA.
Curr Biol. 2006 Sep 19;16(18):1771-82. doi: 10.1016/j.cub.2006.07.055.
Male-derived Sex-peptide (SP) elicits egg laying and rejection of courting males in mated Drosophila females. Little is known about the genes that specify the underlying neuronal circuits and mediate this switch in female sexual behavior.
Here we show that the egghead gene involved in glycosphingolipid biosynthesis provides an essential component to the SP response. We have isolated viable alleles of the vital egghead gene that abolish egghead expression from a distal promoter resulting in the absence of the largest transcript of this complex transcription unit. Temporally and spatially restricted expression of egghead revealed a requirement for egghead early in the development of apterous-expressing ventral nerve cord neurons to rescue the SP response. In viable egghead alleles, these ascending interneurons, three per abdominal and seven per thoracic hemisegment, fail to innervate the central brain. egghead expression in apterous neurons rescues neuronal targeting and the response to SP. Furthermore, neurotransmission in apterous neurons is required to elicit the SP response.
Together with the former finding of SP binding to afferent nerves , these results suggest that SP-mediated modification of sensory input switches female sexual behavior from the virgin to the mated state.
雄性来源的性肽（SP）可引发已交配的果蝇雌性产卵并拒绝求偶雄性。对于指定潜在神经回路并介导雌性性行为这种转变的基因，我们了解甚少。
在此我们表明，参与糖鞘脂生物合成的卵头基因是SP反应的重要组成部分。我们从一个远端启动子分离出了使卵头基因表达缺失的有活力的等位基因，导致这个复杂转录单元最大转录本的缺失。卵头基因在时间和空间上的受限表达表明，在表达无翅基因的腹侧神经索神经元发育早期需要卵头基因来挽救SP反应。在有活力的卵头基因等位基因中，这些上升性中间神经元，每个腹节有三个，每个胸半节有七个，无法支配中枢脑。无翅基因神经元中的卵头基因表达可挽救神经元靶向和对SP的反应。此外，无翅基因神经元中的神经传递是引发SP反应所必需的。
结合之前关于SP与传入神经结合的发现，这些结果表明，SP介导的感觉输入修饰将雌性性行为从处女状态转变为交配状态。
