Dendrites are dispensable for basic motoneuron function but essential for fine tuning of behavior
Dendrites are dispensable for basic motoneuron function but essential for fine tuning of behavior
复制标题
DOI：
10.1073/pnas.1416247111
复制
发表时间：
2014-12-16
影响因子：
11.1
通讯作者：
Duch, Carsten
中科院分区：
文献类型：
--
作者：
Ryglewski, Stefanie;Kadas, Dimitrios;Duch, Carsten
树突是高度复杂的 3D 结构，定义神经元形态和连接性，是突触输入的主要部位。树突结构的缺陷与脑部疾病高度相关。然而，树突结构缺陷对神经元功能和行为表现的确切影响仍然未知。在这里，我们通过使用遗传工具选择性地消除已识别的果蝇翅膀运动神经元中的树突而不影响其他神经元特性来探测树突功能。我们发现这些运动神经元树突对于突触靶向、行为过程中正常的神经元活动模式和基本行为表现来说出乎意料地是可有可无的。然而，复杂的运动行为（例如飞行高度控制和离散求偶歌曲元素之间的切换）的显着性能缺陷随着树突缺陷的程度而变化。据我们所知，我们的观察提供了第一个直接证据，表明复杂的树突结构对于在强大的、进化受限的行为程序中进行微调和适应性至关重要，而这对于交配成功和生存至关重要。我们推测，观察到的表现缺陷随结构缺陷程度的变化与进行性神经系统疾病中结构缺陷不断发展期间智力障碍的逐渐增加是一致的。
Dendrites are highly complex 3D structures that define neuronal morphology and connectivity and are the predominant sites for synaptic input. Defects in dendritic structure are highly consistent correlates of brain diseases. However, the precise consequences of dendritic structure defects for neuronal function and behavioral performance remain unknown. Here we probe dendritic function by using genetic tools to selectively abolish dendrites in identified Drosophila wing motoneurons without affecting other neuronal properties. We find that these motoneuron dendrites are unexpectedly dispensable for synaptic targeting, qualitatively normal neuronal activity patterns during behavior, and basic behavioral performance. However, significant performance deficits in sophisticated motor behaviors, such as flight altitude control and switching between discrete courtship song elements, scale with the degree of dendritic defect. To our knowledge, our observations provide the first direct evidence that complex dendrite architecture is critically required for fine-tuning and adaptability within robust, evolutionarily constrained behavioral programs that are vital for mating success and survival. We speculate that the observed scaling of performance deficits with the degree of structural defect is consistent with gradual increases in intellectual disability during continuously advancing structural deficiencies in progressive neurological disorders.