Related Experiment Video
Updated: Mar 31, 2026

Purification of the Dendritic Filopodia-rich Fraction
Published on: May 2, 2019
The KIF3B/B/KAP3 tail domain specifically facilitates TRIM46 transport to the axon initial segment
Xuguang Jiang1, Sotaro Ichinose2, Tadayuki Ogawa3
1Department of Cell Biology and Anatomy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
None:
Intracellular transport is essential for neuronal organization, yet how motor proteins achieve cargo selectivity remains incompletely understood. Kinesin-2 motors transport diverse cargos through the heterotrimeric KIF3/KAP3 complex, but whether variations in assembly composition contribute to functional specificity has been unclear. This study provides evidence for heterogeneity in neuronal KIF3/KAP3 assemblies, including a KIF3B-enriched, KAP3-associated population in addition to the canonical KIF3A/B/KAP3 complex. Biochemical and cellular analyses support a preferential association between this KIF3B-enriched assembly and TRIM46, a protein required for axon initial segment organization. Structural analyses further suggest that differences in tail conformation accompany distinct assembly states and may underlie cargo selectivity. Together, these findings support a model in which compositional and structural diversity within kinesin-2 complexes contributes to spatially regulated transport during neuronal development.
Related Concept Videos
Tail-anchoring of Proteins in the ER Membrane
Mechanism of Filopodia Formation
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Anaphase A and B
Plus-end depolymerization releases tubulin heterodimers from the terminal region of the microtubule. As tubulin subunits are lost, the Ndc80 complexes detach...
Disassembly of Intermediate Filaments
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Destabilization of Microtubules
Mechanism of Lamellipodia Formation

