Macrophage stimulating protein is a neurotrophic factor for a sub-population of adult nociceptive sensory neurons.
Macrophage stimulating protein (MSP) is a pleiotropic growth factor that signals via the RON receptor tyrosine kinase. Here we demonstrate that MSP increases the proportion of cultured adult mouse DRG neurons displaying discernable neuritic processes and promotes the elongation and branching of these processes in a dose dependent manner. RON expression in adult DRG is largely restricted to nerve growth factor (NGF)-responsive nociceptive neurons, and MSP mimics the effects of NGF by increasing the expression of several mRNAs that encode functionally important proteins that are characteristically expressed by this neuronal sub-population. MSP mRNA is expressed at high levels in the peripheral target fields of DRG somatic afferents, but is undetectable in DRG, spinal cord or freshly dissected sciatic nerve. These results suggest that MSP is a peripheral target-derived neurotrophic factor for NGF-responsive adult DRG neurons.
Franklin
Sarah L
SL
Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF103US, Wales, UK.
Davies
Alun M
AM
Wyatt
Sean
S
D000818:Animals; D005727:Ganglia, Spinal / Q000166:cytology*; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D051379:Mice; D009414:Nerve Growth Factors / Q000378:metabolism*; D016501:Neurites / Q000378:metabolism / Q000648:ultrastructure; D009619:Nociceptors / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D020917:Receptor, trkA / Q000378:metabolism; D017450:Receptors, Opioid, mu / Q000235:genetics / Q000378:metabolism; D000074025:TRPA1 Cation Channel; D050916:TRPV Cation Channels / Q000235:genetics / Q000378:metabolism; D050051:Transient Receptor Potential Channels / Q000235:genetics / Q000378:metabolism
D009414:Nerve Growth Factors; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D017450:Receptors, Opioid, mu; D000074025:TRPA1 Cation Channel; D050916:TRPV Cation Channels; C493921:TRPV1 protein, mouse; D050051:Transient Receptor Potential Channels; C475685:Trpa1 protein, mouse; C082332:macrophage stimulating protein; D017228:Hepatocyte Growth Factor; C080835:RON protein; D020794:Receptor Protein-Tyrosine Kinases; D020917:Receptor, trkA