DNM3

DNM3 is a human gene that encodes dynamin-3, a member of the dynamin family of large GTPases involved in membrane remodeling. Dynamins play a crucial role in the scission of vesicles from membranes during endocytosis and various trafficking steps, enabling the internalization and recycling of membrane components and receptors.

Dynamin-3 shares the conserved domain architecture characteristic of dynamins, including an N-terminal GTPase domain, a middle domain, a pleckstrin homology (PH) domain, a GTPase effector domain, and a C-terminal proline-rich domain. It assembles into oligomeric structures, such as collars around vesicle necks, in a GTP-dependent manner and uses GTP hydrolysis to drive membrane scission.

The DNM3 gene produces multiple transcript variants, resulting in several protein isoforms with potentially distinct localizations and roles. Expression studies show notable presence in brain and testis, with broader but variable expression in other tissues depending on developmental stage and cellular context. In neurons, dynamin-3 is implicated in synaptic vesicle endocytosis and recycling, contributing to the maintenance of synaptic transmission. In non-neuronal cells, it participates in clathrin-mediated endocytosis and other receptor internalization pathways.

DNM3 interacts with SH3-domain-containing proteins such as amphiphysin, endophilin, and syndapin, which help recruit dynamin to sites of endocytosis. Its activity is regulated by GTP binding and hydrolysis and by lipid interactions via the PH domain.

Compared with its paralogs DNM1 and DNM2, dynamin-3 exhibits distinct tissue distribution and regulatory patterns, reflecting specialized roles in vertebrate cells. While the gene has been investigated for potential disease associations, no definitive causal link to a specific hereditary condition has been established.