Almoril-Porras Agustin, Calvo Ana C, Niu Longgang, Beagan Jonathan, Díaz García Malcom, Hawk Josh D, Aljobeh Ahmad, Wisdom Elias M, Ren Ivy, Wang Zhao-Wen, Colón-Ramos Daniel A
Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06536, USA.
Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030, USA.
Cell. 2025 Jan 9;188(1):89-103.e13. doi: 10.1016/j.cell.2024.11.037. Epub 2024 Dec 31.
Synaptic configurations underpin how the nervous system processes sensory information to produce a behavioral response. This is best understood for chemical synapses, and we know far less about how electrical synaptic configurations modulate sensory information processing and context-specific behaviors. We discovered that innexin 1 (INX-1), a gap junction protein that forms electrical synapses, is required to deploy context-specific behavioral strategies underlying thermotaxis behavior in C. elegans. Within this well-defined circuit, INX-1 couples two bilaterally symmetric interneurons to integrate sensory information during migratory behavior across temperature gradients. In inx-1 mutants, uncoupled interneurons display increased excitability and responses to subthreshold sensory stimuli due to increased membrane resistance and reduced membrane capacitance, resulting in abnormal responses that extend run durations and trap the animals in context-irrelevant tracking of isotherms. Thus, a conserved configuration of electrical synapses enables differential processing of sensory information to deploy context-specific behavioral strategies.
突触结构是神经系统处理感官信息以产生行为反应的基础。这在化学突触方面理解得最为透彻，而对于电突触结构如何调节感官信息处理和特定情境行为，我们所知甚少。我们发现，形成电突触的间隙连接蛋白innexin 1（INX-1）是秀丽隐杆线虫在趋温行为中运用特定情境行为策略所必需的。在这个定义明确的神经回路中，INX-1将两个双侧对称的中间神经元连接起来，以便在跨温度梯度的迁移行为中整合感官信息。在inx-1突变体中，未耦合的中间神经元由于膜电阻增加和膜电容减小而表现出兴奋性增加以及对阈下感觉刺激的反应增强，导致异常反应，延长了奔跑持续时间，并使动物陷入与情境无关的等温线追踪中。因此，电突触的保守结构能够对感官信息进行差异处理，从而运用特定情境行为策略。
