dynamin3

Dynamin-3 is a member of the dynamin family of large GTPases involved in membrane remodeling during endocytosis and vesicle trafficking. It is encoded by the DNM3 gene in humans and is one of three dynamin paralogs, alongside DNM1 and DNM2.

Dynamin-3 contains the characteristic domain architecture of dynamins: an N-terminal GTPase domain, a middle domain, a pleckstrin homology (PH) domain that binds phosphoinositides, a GTPase effector domain, and a proline-rich C-terminal tail. The protein can oligomerize and assemble into helical structures around the necks of budding vesicles. GTP hydrolysis drives conformational changes that produce membrane constriction and vesicle scission, enabling vesicle release into the cytoplasm.

DNM3 shows tissue-restricted expression, with notable enrichment in the brain and testis, and multiple transcript variants produced by alternative splicing. In neurons, dynamin-3 has been observed in synaptic membranes and related compartments, consistent with a role in synaptic vesicle recycling and neurotransmission.

Functionally, dynamin-3 participates in clathrin-mediated endocytosis by mediating the fission of vesicles from the plasma membrane. While it shares core roles with dynamin-1 and dynamin-2, dynamin-3 may contribute in a tissue-specific manner and interact with neuron-specific adaptor and accessory proteins, supporting specialized endocytic processes in neural tissue.

In research contexts, defects in dynamin function broadly impact endocytosis and membrane trafficking. Specific disease associations for dynamin-3 are less clearly defined than for other dynamins, and current work focuses on delineating its distinct contributions to neuronal signaling and synaptic plasticity. The dynamin family is evolutionarily conserved, and dynamin-3 preserves the conserved GTPase and lipid-binding motifs that underpin endocytic scission.