scholarly journals Amotl2 interacts with LL5 , localizes to podosomes and regulates postsynaptic differentiation in muscle

2013 ◽  
Vol 126 (10) ◽  
pp. 2225-2235 ◽  
Author(s):  
T. J. Proszynski ◽  
J. R. Sanes
Keyword(s):  
Postsynaptic Differentiation

scholarly journals Neurotrophins regulate agrin-induced postsynaptic differentiation

1999 ◽  
Vol 96 (3) ◽  
pp. 1112-1117 ◽  
Author(s):  
D. G. Wells ◽  
B. A. McKechnie ◽  
S. Kelkar ◽  
J. R. Fallon
Keyword(s):  
Postsynaptic Differentiation

scholarly journals The function of p120 catenin in filopodial growth and synaptic vesicle clustering in neurons

2012 ◽  
Vol 23 (14) ◽  
pp. 2680-2691 ◽  
Author(s):  
Cheng Chen ◽  
Pan P. Li ◽  
Raghavan Madhavan ◽  
H. Benjamin Peng
Keyword(s):  
Synaptic Vesicle ◽  
Motor Neurons ◽  
Rho Gtpases ◽  
Acetylcholine Receptors ◽  
Physical Contact ◽  
Spinal Neurons ◽  
P120 Catenin ◽  
Presynaptic Differentiation ◽  
Nerve Muscle ◽  
Postsynaptic Differentiation

At the developing neuromuscular junction (NMJ), physical contact between motor axons and muscle cells initiates presynaptic and postsynaptic differentiation. Using Xenopus nerve–muscle cocultures, we previously showed that innervating axons induced muscle filopodia (myopodia), which facilitated interactions between the synaptic partners and promoted NMJ formation. The myopodia were generated by nerve-released signals through muscle p120 catenin (p120ctn), a protein of the cadherin complex that modulates the activity of Rho GTPases. Because axons also extend filopodia that mediate early nerve–muscle interactions, here we test p120ctn's function in the assembly of these presynaptic processes. Overexpression of wild-type p120ctn in Xenopus spinal neurons leads to an increase in filopodial growth and synaptic vesicle (SV) clustering along axons, whereas the development of these specializations is inhibited following the expression of a p120ctn mutant lacking sequences important for regulating Rho GTPases. The p120ctn mutant also inhibits the induction of axonal filopodia and SV clusters by basic fibroblast growth factor, a muscle-derived molecule that triggers presynaptic differentiation. Of importance, introduction of the p120ctn mutant into neurons hinders NMJ formation, which is observed as a reduction in the accumulation of acetylcholine receptors at innervation sites in muscle. Our results suggest that p120ctn signaling in motor neurons promotes nerve–muscle interaction and NMJ assembly.

Ionic Control of Postsynaptic Differentiation in Muscle

1989 ◽  
Vol 176 (2S) ◽  
pp. 126-129
Author(s):  
H. BENJAMIN PENG ◽  
DING-LIANG ZHU
Keyword(s):  
Postsynaptic Differentiation

scholarly journals Motoneuron Wnts regulate neuromuscular junction development

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Chengyong Shen ◽  
Lei Li ◽  
Kai Zhao ◽  
Lei Bai ◽  
Ailian Wang ◽  
...  
Keyword(s):  
Neuromuscular Junction ◽  
Synaptic Vesicles ◽  
Skeletal Muscles ◽  
Motor Behavior ◽  
Nerve Terminals ◽  
Presynaptic Differentiation ◽  
Gene Mutant ◽  
Postsynaptic Differentiation ◽  
Presynaptic Assembly

The neuromuscular junction (NMJ) is a synapse between motoneurons and skeletal muscles to control motor behavior. Unlike extensively investigated postsynaptic differentiation, less is known about mechanisms of presynaptic assembly. Genetic evidence of Wnt in mammalian NMJ development was missing due to the existence of multiple Wnts and their receptors. We show when Wnt secretion is abolished from motoneurons by mutating the Wnt ligand secretion mediator (Wls) gene, mutant mice showed muscle weakness and neurotransmission impairment. NMJs were unstable with reduced synaptic junctional folds and fragmented AChR clusters. Nerve terminals were swollen; synaptic vesicles were fewer and mislocated. The presynaptic deficits occurred earlier than postsynaptic deficits. Intriguingly, these phenotypes were not observed when deleting Wls in muscles or Schwann cells. We identified Wnt7A and Wnt7B as major Wnts for nerve terminal development in rescue experiments. These observations demonstrate a necessary role of motoneuron Wnts in NMJ development, in particular presynaptic differentiation.

scholarly journals Nerve, Muscle, and Synaptogenesis

Cells ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1448 ◽  
Author(s):  
Swenarchuk
Keyword(s):  
Experimental Validation ◽  
Synapse Formation ◽  
Current Model ◽  
Neuromuscular Synapse ◽  
Model System ◽  
Integrin Signaling ◽  
Neuromuscular Synapses ◽  
Nerve Muscle ◽  
Postsynaptic Differentiation ◽  
Pericellular Proteolysis

The vertebrate skeletal neuromuscular junction (NMJ) has long served as a model system for studying synapse structure, function, and development. Over the last several decades, a neuron-specific isoform of agrin, a heparan sulfate proteoglycan, has been identified as playing a central role in synapse formation at all vertebrate skeletal neuromuscular synapses. While agrin was initially postulated to be the inductive molecule that initiates synaptogenesis, this model has been modified in response to work showing that postsynaptic differentiation can develop in the absence of innervation, and that synapses can form in transgenic mice in which the agrin gene is ablated. In place of a unitary mechanism for neuromuscular synapse formation, studies in both mice and zebrafish have led to the proposal that two mechanisms mediate synaptogenesis, with some synapses being induced by nerve contact while others involve the incorporation of prepatterned postsynaptic structures. Moreover, the current model also proposes that agrin can serve two functions, to induce synaptogenesis and to stabilize new synapses, once these are formed. This review examines the evidence for these propositions, and concludes that it remains possible that a single molecular mechanism mediates synaptogenesis at all NMJs, and that agrin acts as a stabilizer, while its role as inducer is open to question. Moreover, if agrin does not act to initiate synaptogenesis, it follows that as yet uncharacterized molecular interactions are required to play this essential inductive role. Several alternatives to agrin for this function are suggested, including focal pericellular proteolysis and integrin signaling, but all require experimental validation.

Sign in / Sign up

Export Citation Format

Share Document