Strauss R, Heisenberg M
Theodor-Boveri-Institut für Biowissenschaften, Lehrstuhl für Genetik, Würzburg, Germany.
J Neurosci. 1993 May;13(5):1852-61. doi: 10.1523/JNEUROSCI.13-05-01852.1993.
In order to elucidate the behavioral significance of the central complex (CC), we have examined walking in 15 Drosophila mutant strains belonging to eight independent X-linked genes that affect the structure of the CC. Compared to four different wild-type strains, all are impaired either in a general or in a paradigm-dependent manner. Behavioral deficits concern walking activity, walking speed, or "straightness of walking" as measured in an object fixation task, in fast phototaxis, and in negative geotaxis. Behavioral deficits of three strains with mutations in different genes were studied in detail using mosaic analysis and high-speed cinematography. In all cases the focus for declining walking activity is located in the brain and is fully correlated with the respective defect of the CC. A high correlation between the degree of the behavioral impairment and the severity of the structural defect in two strains further adds to the evidence. Declining walking activity is not an unspecific side effect of structural brain defects, as steady walking is observed in structural mutants of the visual system and mushroom bodies. In mutant flies no-bridgeKS49 (nob), step size as a function of the stepping period is reduced. The focus of the resulting reduced average and maximum walking speeds resides in the brain and, again, the behavioral impairment fully correlates with the structural defects of the CC. While no indication is found for a role of the CC in setting up the basic stepping rhythm in straight walking (a respective phenotype in mutant central-complexKS181 flies resides in the ventral ganglion), a role in turning and start/stop maneuvers is suggested by aberrations in the stepping pattern of nob flies during such episodes.
为了阐明中央复合体（CC）的行为学意义，我们研究了15种果蝇突变株的行走行为，这些突变株属于8个独立的X连锁基因，它们会影响中央复合体的结构。与4种不同的野生型菌株相比，所有突变株在一般或范式依赖的方式上都存在缺陷。行为缺陷涉及行走活动、行走速度或在物体固定任务、快速趋光性和负趋地性中测量的“行走直线度”。使用镶嵌分析和高速摄影技术，详细研究了3种不同基因突变株的行为缺陷。在所有情况下，行走活动下降的焦点都位于大脑中，并且与中央复合体的相应缺陷完全相关。两种菌株中行为损伤程度与结构缺陷严重程度之间的高度相关性进一步证明了这一点。行走活动下降不是大脑结构缺陷的非特异性副作用，因为在视觉系统和蘑菇体的结构突变体中观察到稳定的行走。在突变果蝇no-bridgeKS49（nob）中，步长作为步频的函数减小。由此导致的平均和最大行走速度降低的焦点位于大脑中，并且行为损伤再次与中央复合体的结构缺陷完全相关。虽然没有发现中央复合体在建立直线行走的基本步频中起作用（突变的中央复合体KS181果蝇的相应表型位于腹神经节），但在转弯和启动/停止动作中起作用的证据是由nob果蝇在此类情况下的步姿异常所暗示的。
