A Small Peptide Sequence is Sufficient for Initiating Kinesin‐1 Activation Through Part of TPR Region of KLC1

Abstract

Kinesin-1 anterogradely transports vesicles containing cargo proteins when a protein-protein interaction activates it from an inhibited state. The C-terminal cytoplasmic region of kinesin-1 cargo protein Alcadeinα (Alcα) interacts with the KLC1 subunit's tetratricopeptide repeat (TPR) region, activating kinesin-1's association with vesicles and anterograde transport. We found that either of two 10-amino-acid WD motifs in Alcα cytoplasmic region was necessary and sufficient to initiate this activation. An artificial transmembrane protein containing either WD motif induced kinesin-1's vesicular association and anterograde transport in a KLC-dependent manner, even in the normally inhibiting presence of excess KLC1, thus allowing us to analyze the KLC1 TPR-WD functional interaction in detail in vivo. A part of TPR region was dispensable for the WD motifs' activation of kinesin-1 and transport, indicating that only part of the TPR structure is required for this function in vivo. For a different kinesin-1 cargo protein, JIP1, an 11-amino-acid C-terminal region was sufficient to recruit KLC1 to vesicles, but did not activate transport. These observations suggest that structurally different TPR-interacting peptides may have different effects on kinesin-1. This mechanism may partly explain how kinesin-1 can organize the transport of a wide variety of cargo molecules.

Membrane damage-induced vesicle–vesicle fusion of dysferlin-containing vesicles in muscle cells requires microtubules and kinesin

“…Interestingly, most KIF5B labeled dysferlin-containing vesicles did not show long-range processive movement and are limited to local movements in resting L6 myotubes. These findings are consistent with reports describing processive and non-processive movements of kinesin-bound cargoes (36,37). Possible explanations for the non-processive behavior of a subpopulation of kinesin-containing dysferlin vesicles are that KIF5B may be bound to dysferlin-containing vesicles without sufficiently activating kinesin motor activity or without actively engaging microtubules (36) or perhaps the clustering of vesicles limits their motility or anchors them to another subcellular structure.…”

Kinesin-1 promotes post-Golgi trafficking of NCAM140 and NCAM180 to the cell surface

“…For transfection of cells, cDNAs coding for full length non-mutated hNCAM180 (Diestel et al, 2004); hNCAMΔCT (Boutin et al, 2009);rat NCAM140-ID (Leshchyns'ka et al, 2003); rat NCAM-ID-729-750, rat NCAM-ID-777-810, and Sec8Y401F,Y616F (Chernyshova et al, 2011); rat NCAM-ID-748-777 (Li et al, 2013); GFP-KLC1 and GFP-KHC1 (generous gifts of Toshiharu Suzuki, Hokkaido University, Sapporo, Japan) (Araki et al, 2007;Kawano et al, 2012), and GFP (Clontech) were used. To construct cDNA coding for hNCAM180-Δ747-754, site-specific mutagenesis was carried out using the overlap extension PCR method (Ho et al, 1989) with hNCAM180 as a template.…”

The light chains of kinesin-1 are autoinhibited

“…This is achieved via an intramolecular interaction in which the C-terminal isoleucine-alanine-lysine (IAK) motif (and flanking amino acids) of a single KHC tail binds at the N-terminal motor dimer interface and participates in a "double-lockdown" mechanism whereby it cross-links the motor domains preventing movement of the neck linker region that is required for ADP release (7)(8)(9)(10)(11)(12). In the cargo-bound active state, tail-mediated inhibition is relieved resulting in a more elongated structure that is able to hydrolyze ATP and translocate along MTs (12)(13)(14)(15)(16). As well as binding to cargoes, the KLCs are thought to regulate KHC autoinhibition, although the molecular mechanism(s) that couple these two functions are unclear (17).…”