NT3 expressed in skin causes enhancement of SA1 sensory neurons that leads to postnatal enhancement of Merkel cells

  title={NT3 expressed in skin causes enhancement of SA1 sensory neurons that leads to postnatal enhancement of Merkel cells},
  author={Robin F. Krimm and Brian M. Davis and C. Jeffery Woodbury and Kathryn M. Albers},
  journal={Journal of Comparative Neurology},
To determine the role of NT3 in the postnatal maturation of Merkel cell (MC) sensory neurite complexes (touch domes), we examined the development of their neural and end‐organ components in wild‐type and transgenic mice that overexpress NT3 (NT3‐OE). Touch domes are sensory complexes of the skin that contain specialized MCs innervated by slowly adapting type 1 (SA1) neurons. Touch domes are dependent on NT3 and, though formed in newborn mice that lack NT3, are severely depleted during postnatal… 

Overexpression of neurotrophin 4 in skin enhances myelinated sensory endings but does not influence sensory neuron number

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Merkel Cell-Driven BDNF Signaling Specifies SAI Neuron Molecular and Electrophysiological Phenotypes

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Insight is given into how Merkel cells develop and how they are replaced in adult mice, and it is found that direct contact from SAI neurons is not required for Merkel cell production.

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It is concluded that neuropeptide release and neurotransmitter exocytosis may be two distinct pathways that are differentially regulated.

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Neural Hedgehog signaling maintains stem cell renewal in the sensory touch dome epithelium

Skin denervation reveals that renewal of touch dome stem cells requires a perineural microenvironment, and deleting Sonic hedgehog (Shh) in neurons or Smoothened in the epidermis demonstrates that Shh is an essential niche factor that maintains touch Dome stem cells.

Scaling Proprioceptor Gene Transcription by Retrograde NT3 Signaling

It is found that the expression of many proprioceptor-enriched genes is dramatically altered by genetic NT3 elimination, independent of survival-related activities, pointing to life-long gene expression plasticity in sensory neurons.



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Results indicate that overexpression of NT3 in skin ofNT3(+/-) knockout mice rescued most cutaneous neurons lost in NT3( +/-) mice, but was unable to rescue NT3-dependent neurons that project to noncutaneous sensory targets.

Cutaneous overexpression of NT-3 increases sensory and sympathetic neuron number and enhances touch dome and hair follicle innervation

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Results show that NT‐3 signaling is not required for the differentiation of Merkel cells, but that it is essential for their postnatal survival.

Developmental changes in NT3 signalling via TrkA and TrkB in embryonic neurons.

The results show that NT3 can signal through TrkA and TrkB in neurons at certain stages of development and may explain why the phenotype of NT3−/− mice is more severe than that of trkC− /− mice.

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Development of Merkel cell populations with contrasting sensitivities to neonatal deafferentation in the rat whisker pad.

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