Thor S, Thomas J B
Molecular Neurobiology Laboratory, The Salk Institute, San Diego, California 92186, USA.
Neuron. 1997 Mar;18(3):397-409. doi: 10.1016/s0896-6273(00)81241-6.
We have isolated the Drosophila homolog of the vertebrate islet-1 and islet-2 genes, two members of the LIM homeodomain family implicated in the transcriptional control of motor neuronal differentiation. Similar to vertebrates, Drosophila islet is expressed in a discrete subset of embryonic motor neurons and interneurons that includes the dopaminergic and serotonergic cells of the ventral nerve cord. In contrast to mouse where mutation of islet-1 leads to loss of neurons due to programmed cell death, Drosophila islet is not required for neuron survival. Instead, loss of islet function causes defects in axon pathfinding and targeting plus loss of dopamine and serotonin synthesis. Ectopic expression of islet induces both specific alterations in pathfinding and changes in neurotransmitter identity. These findings indicate that islet coordinately controls two distinct aspects of neuronal identity.
我们分离出了脊椎动物胰岛-1和胰岛-2基因的果蝇同源物，这两个LIM同源域家族成员参与运动神经元分化的转录控制。与脊椎动物相似，果蝇胰岛在胚胎运动神经元和中间神经元的一个离散子集中表达，其中包括腹神经索的多巴胺能和5-羟色胺能细胞。与小鼠不同，在小鼠中胰岛-1的突变会因程序性细胞死亡导致神经元丢失，而果蝇的神经元存活并不需要胰岛。相反，胰岛功能丧失会导致轴突寻路和靶向缺陷，以及多巴胺和5-羟色胺合成丧失。胰岛的异位表达会诱导寻路的特定改变和神经递质特性的变化。这些发现表明，胰岛协同控制神经元特性的两个不同方面。
