McNeil G P, Zhang X, Genova G, Jackson F R
Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Neuron. 1998 Feb;20(2):297-303. doi: 10.1016/s0896-6273(00)80457-2.
Analysis of the Drosophila lark gene indicates that it encodes an RNA-binding protein that functions as a regulatory element of the circadian clock output pathway controlling adult eclosion. We now demonstrate that the lark RNA-binding protein oscillates in abundance during the circadian cycle; importantly, the phasing of the lark rhythm is consistent with gene-dosage studies, which indicate that the protein behaves as a repressor molecule. The lark protein rhythm persists in constant conditions (continuous darkness and constant temperature) and is eliminated by period gene null mutations, confirming that it is under clock control and suggesting that it acts as an output mechanism that mediates the temporal regulation of adult eclosion. We also show that lark protein oscillates in abundance within a defined group of neuropeptide (CCAP) -containing neurons of the ventral nervous system (VNS), which in other insects are thought to comprise cellular elements of the clock output pathway regulating eclosion.
对果蝇lark基因的分析表明，它编码一种RNA结合蛋白，该蛋白作为昼夜节律输出途径的调节元件，控制成虫羽化。我们现在证明，lark RNA结合蛋白在昼夜周期中丰度振荡；重要的是，lark节律的相位与基因剂量研究一致，这表明该蛋白起着阻遏分子的作用。lark蛋白节律在恒定条件下（持续黑暗和恒定温度）持续存在，并被周期基因无效突变消除，证实它受生物钟控制，并表明它作为一种输出机制，介导成虫羽化的时间调节。我们还表明，lark蛋白在腹侧神经系统（VNS）中一组特定的含神经肽（CCAP）的神经元内丰度振荡，在其他昆虫中，这些神经元被认为构成调节羽化的生物钟输出途径的细胞元件。
