Tomasi Tatiana, Hakeda-Suzuki Satoko, Ohler Stephan, Schleiffer Alexander, Suzuki Takashi
Max Planck Institute of Neurobiology, Am Klopferspitz 18, D-82152 Martinsried, Germany.
Neuron. 2008 Mar 13;57(5):691-704. doi: 10.1016/j.neuron.2008.01.012.
During Drosophila visual system development, photoreceptor (R) axons choose their correct paths and targets in a step-wise fashion. R axons with different identities make specific pathfinding decisions at different stages during development. We show here that the transmembrane protein Golden goal (Gogo), which is dynamically expressed in all R neurons and localizes predominantly to growth cones, is required in two distinct steps of R8 photoreceptor axon pathfinding: Gogo regulates axon-axon interactions and axon-target interactions in R8 photoreceptor axons. gogo loss-of-function and gain-of-function phenotypes suggest that Gogo mediates repulsive axon-axon interaction between R8 axons to maintain their proper spacing, and it promotes axon-target recognition at the temporary layer to enable R8 axons to enter their correct target columns in the medulla. From detailed structure-function experiments, we propose that Gogo functions as a receptor that binds an unidentified ligand through its conserved extracellular domain.
在果蝇视觉系统发育过程中，光感受器（R）轴突以逐步的方式选择其正确的路径和靶标。具有不同身份的R轴突在发育的不同阶段做出特定的路径寻找决定。我们在此表明，跨膜蛋白金色目标（Gogo）在所有R神经元中动态表达，且主要定位于生长锥，在R8光感受器轴突路径寻找的两个不同步骤中是必需的：Gogo调节R8光感受器轴突中的轴突-轴突相互作用和轴突-靶标相互作用。gogo功能丧失和功能获得表型表明，Gogo介导R8轴突之间的排斥性轴突-轴突相互作用以维持其适当间距，并促进在临时层的轴突-靶标识别，以使R8轴突能够进入髓质中的正确靶标柱。通过详细的结构-功能实验，我们提出Gogo作为一种受体，通过其保守的细胞外结构域结合一种未鉴定的配体。
