分子梯度形成视运动转化的突触特异性，这一成果由加州大学S. Lawrence Zipursky研究团队经过不懈努力而取得。相关论文于2025年6月4日发表在《自然》杂志上。

课题组人员在LPLC2中解决了这个问题。一种VPN类型，可以检测到迫在眉睫的运动，并优先驱动对来自背侧视野的刺激的逃避行为，腹侧反应逐渐减弱。这与LPLC2的突触输入和输出的背腹侧梯度有关。

在这里，课题组报道LPLC2神经元在视觉空间的不同区域取样，显示出与这些突触梯度相匹配的细胞识别分子的梯度表达。Dpr13通过结合运动前下行神经元介导逃逸的DIP-ε来塑造LPLC2输出。Beat-VI通过在上游运动检测神经元中结合Side-II来塑造LPLC2输入。功能获得和功能丧失实验表明，这些分子梯度对突触数量的确定具有指导意义。这些模式依次微调对刺激的感知并驱动行为反应。在脊椎动物的大脑中也观察到类似的神经元类型的转录组变异，这种变异可能通过细胞识别分子的梯度来决定突触的数量，这种梯度是通过遗传上固有的程序和经验作用的。

据介绍，大脑是如何将视觉输入转化为特定的运动动作的在果蝇中，视觉投射神经元（VPNs）通过将视网膜位置信息转换为大脑中的突触数来完成这种视觉运动转换。这种现象的分子基础尚不清楚。

附：英文原文

Title: Molecular gradients shape synaptic specificity of a visuomotor transformation

Author: Dombrovski, Mark, Zang, Yixin, Frighetto, Giovanni, Vaccari, Andrea, Jang, HyoJong, Mirshahidi, Parmis S., Xie, Fangming, Sanfilippo, Piero, Hina, Bryce W., Rehan, Aadil, Hussein, Roni H., Mirshahidi, Pegah S., Lee, Catherine, Morris, Aileen, Frye, Mark A., von Reyn, Catherine R., Kurmangaliyev, Yerbol Z., Card, Gwyneth M., Zipursky, S. Lawrence

Issue&Volume: 2025-06-04

Abstract: How does the brain convert visual input into specific motor actions1,2 In Drosophila, visual projection neurons (VPNs)3,4 perform this visuomotor transformation by converting retinal positional information into synapse number in the brain5. The molecular basis of this phenomenon remains unknown. We addressed this issue in LPLC2 (ref. 6), a VPN type that detects looming motion and preferentially drives escape behaviour to stimuli approaching from the dorsal visual field with progressively weaker responses ventrally. This correlates with a dorsoventral gradient of synaptic inputs into and outputs from LPLC2. Here we report that LPLC2 neurons sampling different regions of visual space exhibit graded expression of cell recognition molecules matching these synaptic gradients. Dpr13 shapes LPLC2 outputs by binding DIP-ε in premotor descending neurons mediating escape. Beat-VI shapes LPLC2 inputs by binding Side-II in upstream motion-detecting neurons. Gain-of-function and loss-of-function experiments show that these molecular gradients act instructively to determine synapse number. These patterns, in turn, fine-tune the perception of the stimulus and drive the behavioural response. Similar transcriptomic variation within neuronal types is observed in the vertebrate brain7 and may shape synapse number via gradients of cell recognition molecules acting through both genetically hard-wired programs and experience.

DOI: 10.1038/s41586-025-09037-4

Source: https://www.nature.com/articles/s41586-025-09037-4