Work

MEF-2 repression of GEM-4/Copine expression decreases muscle excitability by increasing gap junction coupling

Year: 2026

Type: preprint

Abstract: Activity induced gene expression promotes behavioral plasticity (including several forms of learning and memory) by altering synaptic connectivity and neuron excitability. While several transcriptional targets modify synapses, little is known about targets regulating excitability. Here, we identify a single MEF-2 and CRH-1/CREB transcriptional target, gem-4 /Copine, whose expression increases the excitability of C. elegans body muscles. In muscles, gem-4 expression is repressed by MEF-2 and is induced by CRH-1. GEM-4 expression in muscles decreases the number of gap junctions, thereby increasing membrane resistance and excitability. These results identify activity induced copine expression as a mechanism to control gap junction coupling and excitability.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.04.09.717484

Authors: Luna Gao, Edward Pym, Stephen Nurrish, Joshua M. Kaplan

Institutions: Harvard University, Massachusetts General Hospital, Howard Hughes Medical Institute, Brandeis University

Language: English

Topic: Connexins and lens biology

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Institutes of Health, National Institute of General Medical Sciences