What is the composition of the gap junctions?

Gap junctions are primarily composed of connexins, which are a family of integral membrane proteins. Each gap junction channel is formed by the docking of two connexons (hemichannels), one from each adjacent cell, creating a direct pathway for cellular communication. These channels allow the passage of ions and small molecules, facilitating intercellular signaling and coordination. The specific composition of connexins can vary between cell types, influencing the properties and permeability of the gap junctions.