Induction of presynaptic differentiation in cultured neurons by extracellular matrix components.
Motoneurons reinnervating skeletal muscles form nerve terminals at sites of contact with a specialized basal lamina. To analyse the molecules and mechanisms that underly these responses, we introduce two systems in which basal lamina-derived components induce presynaptic differentiation of cultured neurons from chick ciliary ganglia in the absence of a postsynaptic cell. In one, ciliary neurites that contact substrates coated with a recombinant laminin beta2 fragment form varicosities that are rich in synaptic vesicle proteins, depleted of neurofilaments, and capable of depolarization-dependent exocytosis and endocytosis. Thus, a single molecule can trigger a complex, coordinated program of presynaptic differentiation. In a second system, neurites growing on cryostat sections of adult kidney form vesicle-rich, neurofilament-poor arbors on glomeruli. Glomerular basal lamina, like synaptic basal lamina, is rich in laminin beta2 and collagen (alpha3-5) IV. However, glomeruli from mutant mice lacking these proteins were capable of inducing differentiation, suggesting the glomerulus as a source of novel presynaptic organizing molecules.
Son
Y J
YJ
Department of Anatomy and Neurobiology, Washington University School of Medicine, St Louis, MO 63110, USA.
Patton
B L
BL
Sanes
J R
JR
D000818:Animals; D002450:Cell Communication / Q000187:drug effects / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D002642:Chick Embryo; D002924:Ciliary Body / Q000166:cytology; D016326:Extracellular Matrix Proteins / Q000494:pharmacology*; D007678:Kidney Glomerulus / Q000737:chemistry / Q000166:cytology; D007797:Laminin / Q000494:pharmacology; D051379:Mice; D009046:Motor Neurons / Q000166:cytology* / Q000187:drug effects*; D018485:Muscle Fibers, Skeletal / Q000166:cytology*; D018482:Muscle, Skeletal / Q000166:cytology; D010446:Peptide Fragments / Q000494:pharmacology; D017729:Presynaptic Terminals / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D016326:Extracellular Matrix Proteins; D007797:Laminin; D010446:Peptide Fragments