Role of Andante/CKIIB in the Drosophila Circadian Clock

了解行为的细胞和分子基础是当代神经科学的一个主要目标 在这方面，果蝇已被证明是分子生物学的一个极好的模型系统。 行为和神经系统的遗传学研究。本申请提出了果蝇的研究， 被称为行板的昼夜节律突变体。该突变体表现出昼夜节律的长周期表型（比正常长约2小时）。 野生型），并且观察到这样的表型LBR成虫运动活动和成虫羽化节律， 与分子振荡器上的效应一致。此外，还对行板的遗传嵌合体进行了分析， 表明头部（可能是神经）组织的功能需求。行板突变 已被映射到X染色体区域10 E内的小基因组间隔。最近，我们发现 新的转座子插入等位基因的基因，这使我们能够开始定义的物理限制， 行板转录单位。我们的初步研究强烈表明，行板编码酪蛋白 激酶II（CKII）[3]直系同源物，CKII全酶的已知调节亚基。鉴于已知 翻译后调节对时钟功能重要性，我们假设Andante产物（CKII[3]） 通过CKII_亚基调节一个或多个元件的磷酸化（以及活性或稳定性） 分子振荡器。在这个应用中，我们提出：（1）定义分子限度，并验证 Andante基因的同一性;（2）通过表征一个基因， 现有的Andante点突变体;（3）确定哪些组织和细胞类型需要Andante功能， 正常的昼夜节律周期性;（4）定义行板产物（即， CKII[3]调节生物钟功能;和（5）通过以下方式直接评估CKIIc_活性的昼夜节律要求： 创建和行为表征_亚基变体。因为时钟的机制基本上 在果蝇和哺乳动物之间保守，我们在果蝇中的研究计划对果蝇的进化有明显的影响。 了解人类生物钟和治疗人类病理生理状态， 从昼夜节律的改变中恢复过来。

Understanding the cellular and molecular bases of behavior is a cardinal goal of contemporary neuroscience research, and in this regard, the fruit fly Drosophila has proven to be an excellent model system for molecular genetic investigations of behavior and the nervous system. This application proposes studies of a Drosophila circadian mutant known as Andante. This mutant exhibits a circadian long-period phenotype (-2 h longer than the wild type), and such a phenotype is observed lbr adult locomotor activity and adult eclosion rhythms, consistent with an effect on the molecular oscillator. In addition, a genetic mosaic analysis of Andante indicates a functional requirement within head (and presumably neural) tissues. The Andante mutation has been mapped to a small genomic interval within region 10E of the X chromosome. Recently, we identified new transposon-insertion alleles of the gene, and this has enabled us to begin to define the physical limits of the Andante transcription unit. Our preliminary studies strongly suggest that Andante encodes a Casein Kinase II (CKII) [3 ortholog, a known regulatory subunit of the CKII_/_ holoenzyme. Given the known importance of post-translational regulation for clock function, we hypothesize that Andante product (CKII[3) acts through the CKII_ subunit to regulate phosphorylation (and activity or stability) of one or more elements of the molecular oscillator. In this application, we propose to: (1) define the molecular limits and verify the identity of the Andante gene; (2) explore the molecular basis of the Andante phenotype by characterizing an existing Andante point mutant; (3) determine which tissues and cell types require Andante function for normal circadian periodicity; (4) define the biochemical mechanism through which Andante product (i.e., CKII[3) regulates clock function; and (5) directly assess the circadian requirement for CKIIc_ activity by creating and behaviorally characterizing _ subunit variants. Because the clock mechanism is fimdamentally conserved between flies and mammals, our proposed studies in Drosophila have obvious ramifications for an tmderstanding of the human circadian clock and the treatment of human pathophysiological states that arise from alterations of circadian timing.