STMN3

STMN3, or stathmin 3, is a member of the stathmin family of microtubule-regulating proteins. It encodes a small cytosolic phosphoprotein that participates in the dynamic remodeling of microtubules, a process important for cellular shape changes and intracellular transport. Like other stathmins, STMN3 is thought to promote microtubule depolymerization by binding tubulin dimers, thereby influencing cytoskeletal remodeling in cells.

Expression studies indicate that STMN3 is enriched in the nervous system, with particularly high levels in brain tissue during development. It is detected in neurons and may be present at lower levels in other cell types. This neural enrichment suggests roles in neural development and function, including processes such as neurite outgrowth and neuronal differentiation.

Regulation of STMN3 activity is thought to occur through phosphorylation, a common mechanism for stathmin family proteins. Multiple kinases can phosphorylate stathmins, which generally reduces their microtubule-destabilizing activity and allows microtubule polymerization to proceed. STMN3 is expected to bind tubulin heterodimers and may interact with other proteins upon phosphorylation, including 14-3-3 family members in some contexts. Dimerization with other stathmins or interaction with microtubule-associated proteins may modulate its function.

Functional implications of STMN3 include involvement in neurite extension, axon guidance, and synaptic plasticity, contributing to neural network formation and remodeling. Its precise roles are still being explored, and STMN3 is often studied in relation to other stathmin family members, which collectively regulate microtubule dynamics in development and disease.