GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:11312299

From GONUTS
Jump to: navigation, search
Citation

Terrado, J, Burgess, RW, DeChiara, T, Yancopoulos, G, Sanes, JR and Kato, AC (2001) Motoneuron survival is enhanced in the absence of neuromuscular junction formation in embryos. J. Neurosci. 21:3144-50

Abstract

Approximately half of the motoneurons produced during development die before birth or shortly after birth. Although it is believed that survival depends on a restricted supply of a trophic sustenance produced by the synaptic target tissue (i.e., muscle), it is unclear whether synapse formation per se is involved in motoneuron survival. To address this issue, we counted cranial motoneurons in a set of mutant mice in which formation of neuromuscular junctions is dramatically impaired (i.e., null mutants for agrin, nerve-derived agrin, rapsyn, and MuSK). We demonstrate that in the absence of synaptogenesis, there is an 18-34% increase in motoneuron survival in the facial, trochlear, trigeminal motor, and hypoglossal nuclei; the highest survival occurred in the MuSK-deficient animals in which synapse formation is most severely compromised. There was no change in the size of the mutant motoneurons as compared with control animals, and the morphology of the mutant motoneurons appeared normal. We postulate that the increased axonal branching observed in these mutants leads to a facilitated "access" of the motoneurons to muscle-derived trophic factors at sites other than synapses or that inactivity increases the production of such factors. Finally, we examined motoneurons in double mutants of CNTFRalpha(-/-) (in which there is a partial loss of motoneurons) and MuSK(-/-) (in which there is an increased survival of motoneurons). The motoneuron numbers in the double mutants parallel those of the single MuSK-deficient mice, indicating that synapse disruption can even overcome the deleterious effect of CNTFRalpha ablation.

Links

PubMed

Keywords

Agrin/deficiency; Agrin/genetics; Animals; Animals, Newborn; Axons/pathology; Cell Count; Cell Survival/genetics; Cranial Nerves/cytology; Cranial Nerves/embryology; Mice; Mice, Mutant Strains; Motor Neurons/cytology; Motor Neurons/metabolism; Muscle Proteins/deficiency; Muscle Proteins/genetics; Neuromuscular Junction/embryology; Neuromuscular Junction/genetics; Neuromuscular Junction/pathology; Neuromuscular Junction Diseases/embryology; Neuromuscular Junction Diseases/genetics; Neuromuscular Junction Diseases/metabolism; Neuromuscular Junction Diseases/pathology; Protein Isoforms/deficiency; Protein Isoforms/genetics; Receptor Protein-Tyrosine Kinases/deficiency; Receptor Protein-Tyrosine Kinases/genetics; Receptor, Ciliary Neurotrophic Factor/deficiency; Receptor, Ciliary Neurotrophic Factor/genetics; Receptors, Cholinergic

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

MOUSE:AGRIN

acts_upstream_of_or_within

GO:0043525: positive regulation of neuron apoptotic process

ECO:0000315: mutant phenotype evidence used in manual assertion

MGI:MGI:1929777

P

  • occurs_in:(EMAPA:16659)
  • regulates_o_occurs_in:(CL:0000100)

Seeded From UniProt

complete

MOUSE:CNTFR

acts_upstream_of_or_within

GO:0043524: negative regulation of neuron apoptotic process

ECO:0000315: mutant phenotype evidence used in manual assertion

MGI:MGI:2181046

P

  • occurs_in:(EMAPA:16659)
  • regulates_o_occurs_in:(CL:0000100)

Seeded From UniProt

complete

MOUSE:RAPSN

acts_upstream_of_or_within

GO:0043525: positive regulation of neuron apoptotic process

ECO:0000315: mutant phenotype evidence used in manual assertion

MGI:MGI:2148091

P

  • occurs_in:(EMAPA:16659)
  • regulates_o_occurs_in:(CL:0000100)

Seeded From UniProt

complete

MOUSE:MUSK

acts_upstream_of_or_within

GO:0043525: positive regulation of neuron apoptotic process

ECO:0000315: mutant phenotype evidence used in manual assertion

MGI:MGI:1929066

P

  • occurs_in:(EMAPA:16659)
  • regulates_o_occurs_in:(CL:0000100)

Seeded From UniProt

complete


See also

References

See Help:References for how to manage references in GONUTS.