Myosin X interaction with KIF13B, a crucial pathway for Netrin-1-induced axonal development

Abstract

30Myosin X (Myo X) transports cargos to the tip of filopodia for cell adhesion, migration, and neuronal axon 31 guidance. Deleted in Colorectal Cancer (DCC) is one of Myo X cargos essential for Netrin-1-regulated axon 32 pathfinding. Myo X's function in axon development in vivo and the underlying mechanisms remain poorly 33 understood. Here, we provide evidence for Myo X's function in Netrin-1-DCC regulated axon development 34 in mouse neocortex. Knocking-out (KO) or knocking-down (KD) Myo X in embryonic cortical neurons 35 impairs axon initiation and contralateral branching/targeting. Similar axon deficits are detected in 36Netrin-1-KO or DCC-KD cortical neurons. Myo X interacts with KIF13B (a kinesin family motor protein), 37 which is induced by Netrin-1. Netrin-1 promotes anterograde transportation of Myo X into axons in KIF13B 38 dependent manner. KIF13B-KD cortical neurons exhibit similar axon deficits. These results suggest Myo 39 X-KIF13B as a critical pathway for Netrin-1 promoted axon initiation and branching/targeting. 40 41 KEY WORDS: 42 Myo X, Netrin-1, KIF13B, axon initiation, axon branching 43 44 48 polarization; (2) axon growth and guidance; and (3) axon branching and presynaptic differentiation. During 49 early development of mammalian cortex, the migrating neurons in the intermediate zone (IZ) transit from 50 multipolar to bipolar, with a leading process towards the pia and a trailing process towards the ventricle. 51Once localized into the cortical plate (CP), the leading processes will develop into highly branched dendrites 52 and the trailing processes will become long axons projecting to target regions for further bifurcation (Barnes 53 and Polleux, 2009; Yogev and Shen, 2017). Eventually, axons connect with target neurons to form synapses 54 that are crucial for neuro-transimission. 55Axon development is regulated by intrinsic factors in neurons as well as the micro-envirenmental 56 factors or extracellular guidance cues. Netrin-1 belonges to the netrin family of extracellular guidance cues, 57 which is crucial for axon pathfinding (Colamarino and Tessier-Lavigne, 1995; Braisted et al., 2000). 58Netrin-1 exerts attractive and repulsive effects through two families of receptors, DCC and UNC-5, 59 respectively (Hedgecock et al.

Control of Motor Landing and Processivity by the CAP-Gly Domain in the KIF13B Tail

“…KIF13B has been reported to transport various cargos within cells, such as: Phosphatidylinositol 3,4,5-triphosphate (PIP3) containing lipid vesicles, low-density lipoprotein (LDL) receptor-related protein 1 (LRP1) containing vesicles, Vascular endothelial growth factor receptor 2 (VEGFR2) and Myosin X [40][41][42][43][44][45][46][47][48][49] . The molecular basis of these diverse motor-cargo interactions remains unclear, but some interactions involve the forkhead-associated (FHA) domain or MBS regions of the motor 47,55 (Fig.…”

“…S1). KIF13B is involved in various cellular processes, such as axon formation, neuronal cell polarity, regulation of angiogenesis, directional migration of the primordial germ cell in Xenopus embryos, the uptake of lipoproteins via endocytosis, and the transport of Rab6 secretory vesicles from the Golgi [38][39][40][41][42][43][44][45][46][47][48][49] . More recently, KIF13B has also been observed to move bidirectionally within mammalian primary cilia 50 .…”

KIF21B binds Myosin Va for Spine Entry and regulates Actin Dynamics to control Homeostatic Synaptic Downscaling

“…Different studies reported physical binding 48, 49, 50 or functional interactions 51 between kinesin and myosin motor proteins. Dendritic spines mainly contain actin filaments 8 and myosin motors 6, 29, 42 , however depending on neuronal activity, some dynamic microtubules occasionally polymerize into dendritic spines 9, 11 and regulate cargo transport through kinesin motors, such as the KIF1A-dependent delivery of synaptotagmin IV 10 .…”