STRUCTURAL AND FUNCTIONAL ANALYSIS OF DROSOPHILA MYOSIN V

肌凝蛋白V是一种肌动蛋白依赖性atp酶。在果蝇中，它在大脑中富集。在果蝇myosin V基因ATG起始位点上发现了一个P-lacW插入600 bp的突变体，使我们能够研究有限myosin V对发育中的果蝇的影响。母源贡献的mRNA可能支持纯合子突变幼虫存活到幼虫后期，因为胚胎和早期幼虫没有明显的行为或发育缺陷。神经问题在第三龄时首先显现出来，幼虫的远端部分瘫痪，使它们在背侧翻身时无法翻身，同时也减少了推动它们前进的蠕动波的力量和传播。这些神经缺陷在成年阶段被放大，因为突变体行动缓慢，无法跳跃或飞行。它们的翅膀在身体两侧，基本上是不能动的。这些现象可能是神经学上的，因为它们有正常的肌肉生理，通过偏振光显微镜进行双折射测试。他们还会表现出头部和腿部的震颤。这种舞蹈病进展迅速，新孵化的苍蝇倾向于以几乎正常的速度四处移动，运动变得更慢，更不协调，直到1周死亡。突变体试图梳理毛发，但它们的动作笨拙而缓慢。此外，没有观察到求偶行为。通过精确切除，动员p元素恢复了野生型表型。-非常规肌球蛋白V；果蝇;p元素;GST-fusion蛋白质;

Myosin V functions as an actin-dependent ATPase. In Drosophila it is enriched in the brain. Identification of a mutant bearing a P-lacW insertion 600 bp from the ATG initiation site in the myosin V gene of Drosophila melanogaster has enabled us to study the effects of limited myosin V on the developing fly. Maternally contributed mRNA may support the survival of the homozygote mutant larva into the later larval stages since there are no apparent behavioral or developmental defects in either embryos or in early instar larvae. Neurological problems are first evident in the 3rd instar, where the distal portion of the larva is paralyzed, preventing them from righting themselves when turned on their dorsal side, and also decreasing the force and propagation of the peristaltic wave which propels them forward. These neurological defects are magnified in the adult stages in which mutants are slow moving and unable to jump or fly. Their wings are held at their side and are largely immobile. These phenomena are probably neurological, since they have normal muscle physiology as test by polarized light microscopy for birefringence. They also exhibit a general tremor of their head and legs. This chorea progresses rapidly, with newly hatched flies tending to move around at an almost normal rate, with movement becoming slower and less coordinated until death at 1 week. The mutants attempt grooming behaviors, but their movements are clumsy and slow. Additionally, no courtship behaviors are observed. Mobilization of the P-element has restored the wild type phenotype by precise excision. - unconventional myosin V; Drosophila; P-element; GST-fusion protein;