Physical parameters describing neuronal cargo transport by kinesin UNC-104

TL;DR

This review summarizes in vivo physical parameters of UNC-104 kinesin motor protein-mediated neuronal cargo transport in C. elegans, emphasizing the regulatory role of ARL-8 and aiming to inform future models of synaptic pathology.

Contribution

It provides the first comprehensive in vivo physical parameter data for UNC-104-mediated cargo transport, including force, velocity, and run length, considering regulatory effects.

Findings

Quantitative in vivo parameters of UNC-104 transport are summarized.

ARL-8 deletion affects transport efficiency and parameters.

Data aims to support modeling of transport-related pathologies.

Abstract

In this review, we focus on the kinesin-3 family molecular motor protein UNC-104 and its regulatory protein ARL-8. UNC-104, originally identified in Caenorhabditis elegans (C. elegans), has a primary role transporting synaptic vesicle precursors (SVPs). Although in vitro single-molecule experiments have been performed to primarily investigate the kinesin motor domain, these have not addressed the in vivo reality of the existence of regulatory proteins, such as ARL-8, that control kinesin attachment to/detachment from cargo vesicles, which is essential to the overall transport efficiency of cargo vesicles. To quantitatively understand the role of the regulatory protein, we review the in vivo physical parameters of UNC-104-mediated SVP transport, including force, velocity, run length and run time, derived from wild-type and arl-8-deletion mutant C. elegans. Our future aim is to facilitate the construction of a consensus physical model to connect SVP transport with pathologies related to deficient synapse construction caused by the deficient UNC-104 regulation. We hope that the physical parameters of SVP transport summarized in this review become a useful guide for the development of such model.