UNC-52 localization with respect to longitudinal axon tracts in the ventral and dorsal nerve cords in C. elegans.

UNC-52 /Perlecan is a core basement membrane (BM) component essential for connecting muscle cells to overlying hypodermal cells. In the nervous system of C. elegans , unc-52 ( ra515 ) causes dendritic branching defects in the PVD neuron independent of muscle attachment defects. We found that unc-52 ( ra515 ) also causes axon navigation defects in the ventral nerve cord (VNC). We then examined the localization of UNC-52 with respect to ventral and dorsal nerve cord (DNC) axon tracts. We found that UNC-52 is localized underneath muscle cells as previously observed but is absent from BMs surrounding ventral and dorsal axon tracts at all stages of development.