Evidence for a role of orcokinin-related peptides in the circadian clock controlling locomotor activity of the cockroach Leucophaea maderae
Evidence for a role of orcokinin-related peptides in the circadian clock controlling locomotor activity of the cockroach Leucophaea maderae
复制标题
DOI：
10.1242/jeb.02307
复制
发表时间：
2006-07-15
影响因子：
2.8
通讯作者：
Homberg, Uwe
中科院分区：
文献类型：
--
作者：
Hofer, Sabine;Homberg, Uwe
在蟑螂Leucophaea maderae的大脑中，主生物钟位于额叶，并控制运动活动的昼夜节律。最近，甲壳类动物神经肽orcokinin家族的成员被确定在蟑螂和蝗虫，并通过免疫细胞化学显着存在于AMe。在蟑螂L. maderae，大约30个神经元中的五个建立的细胞群的AMe显示orcokinin免疫染色。通过示踪剂注射到一个AMe和免疫染色与抗orcokinin抗血清，我们在这里表明，一个orcokinin免疫反应腹侧神经元和三个ventromedian神经元直接连接两个AMae。为了确定一个可能的昼夜节律的功能orcokinin在蟑螂，我们注射150 μ mol Asn（13）-orcokinin到附近的AMe在不同的昼夜节律的时间。这些实验导致蟑螂的昼夜运动活动的稳定的相位依赖性相移。由此产生的相响应曲线的形状与光脉冲的相移效应密切匹配，并且其幅度取决于注射肽的量。结合解剖学数据，结果表明orcokinin相关肽在通过对侧复眼的昼夜节律钟的光夹带途径中起重要作用。此外，这项研究提供了第一个证据的orcokinin相关肽在昆虫中的生理作用。
lobe, houses the master circadian clock in the brain of the cockroach Leucophaea maderae and controls circadian rhythms in locomotor activity. Recently, members of the orcokinin family of crustacean neuropeptides were identified in a cockroach and a locust and were shown by immunocytochemistry to be prominently present in the AMe. In the cockroach L. maderae, about 30 neurons in five of six established cell groups of the AMe showed orcokinin immunostaining. By means of tracer injections into one AMe and immunostaining with anti-orcokinin antiserum, we show here that one orcokinin-immunoreactive ventral neuron and three ventromedian neurons directly connect both AMae. To determine a possible circadian function of orcokinin in the cockroach, we injected 150 mu mol Asn(13)-orcokinin into the vicinity of the AMe at different circadian times. These experiments resulted in stable phase-dependent phase shifts of circadian locomotor activity of the cockroach. The shape of the resulting phase-response curve closely matched the phase-shifting effects of light pulses, and its amplitude was dependent on the amount of the injected peptide. Together with the anatomical data, the results suggest that orcokinin-related peptides play an important role in light entrainment pathways to the circadian clock via the contralateral compound eye. This study, furthermore, provides the first evidence for a physiological role of an orcokinin-related peptide in insects.