Increased expression of p75NTR by neural crest-derived cells in vivo during mitosis

The responses to neurotrophic factors may be modulated by changes in the levels of expression of their receptors. The aim of this study was to determine whether neural precursors in vivo show cell cycle phase-dependent changes in expression of p75NTR and Ret. Preparations of embryonic mouse gut were processed for Ret or p75NTR immunohistochemistry to identify neural crest-derived cells, and cells undergoing mitosis were identified using a fluorescent nucleic acid stain. Neural crest-derived cells undergoing mitosis showed over twice the levels of p75NTR immunoreactivity (pixel intensity measured on a confocal microscope) on their surface to that shown by nonmitotic neural crest cells. However, there was no significant difference between the levels of Ret on mitotic and nonmitotic neural crest cells.