Vallés A M, White K
Department of Biology, Brandeis University, Waltham, Massachusetts 02254.
J Neurosci. 1990 Nov;10(11):3646-52. doi: 10.1523/JNEUROSCI.10-11-03646.1990.
In Drosophila, the enzyme dopa decarboxylase (DDC) catalyzes the last step in the biosynthesis of serotonin (5HT) and dopamine. In the present study, the distribution of DDC and one of its biosynthetic products (5HT) was determined in CNSs that were genetic mosaics, composed of neurons that have DDC activity and neurons that lack DDC activity. Phenotypic mosaicism, that is, immunoreactive (IR) and non-IR neurons within the same nervous system, was observed for both DDC and 5HT immunoreactivity. DDC-IR neurons were always 5HT-IR, but some 5HT-IR neurons devoid of DDC immunoreactivity were also observed. 5HT-IR neurons devoid of DDC immunoreactivity were always in close apposition to other DDC-IR neurons. We suggest that in vivo uptake mechanisms are responsible for 5HT accumulation in neurons devoid of DDC immunoreactivity.
在果蝇中，多巴脱羧酶（DDC）催化血清素（5HT）和多巴胺生物合成的最后一步。在本研究中，DDC及其一种生物合成产物（5HT）的分布在由具有DDC活性的神经元和缺乏DDC活性的神经元组成的中枢神经系统遗传嵌合体中进行了测定。对于DDC和5HT免疫反应性，均观察到表型嵌合现象，即在同一神经系统内的免疫反应性（IR）神经元和非IR神经元。DDC-IR神经元总是5HT-IR，但也观察到一些缺乏DDC免疫反应性的5HT-IR神经元。缺乏DDC免疫反应性的5HT-IR神经元总是与其他DDC-IR神经元紧密相邻。我们认为，体内摄取机制负责5HT在缺乏DDC免疫反应性的神经元中的积累。
