title: Regulation of low affinity neurotrophin receptor (p75(NTR)) by early growth response (Egr) transcriptional regulators.
abstract: The low affinity neurotrophin receptor p75(NTR) is a multifunctional receptor with important roles in neurotrophin signaling, axon outgrowth, and oligodendroglia and neuron survival. It is transcriptionally regulated with spatial and temporal precision during nervous system development, injury and regeneration. Very little is known about how p75(NTR) expression is dynamically regulated but it is likely to influence how p75(NTR) signals in particular cellular contexts. Here, we identify the early growth response (Egr) transcriptional regulators, Egr1 and Egr3, as direct modulators of p75(NTR) gene expression. Egr1 and Egr3 bind and transactivate the p75(NTR) promoter in vitro and in vivo, using distinct response elements on the p75(NTR) promoter. Consistent with these results, p75(NTR) expression is greatly diminished in muscle spindle stretch receptors and in peripheral nerve Schwann cells in Egr gene deficient mice. Taken together, the results elucidate a novel mechanism whereby Egr proteins can directly modulate p75(NTR) expression and signaling in vivo.
authors.affiliation: Department of Pathology (Division of Neuropathology), Feinberg School of Medicine, Northwestern University, 303 E Chicago Avenue, Chicago, IL 60611, USA.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Gao
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Daugherty
authors.forename: Warren G
authors.initials: WG
authors.lastname: Tourtellotte
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D051766:Early Growth Response Protein 1 / Q000235:genetics / Q000378:metabolism*; D051776:Early Growth Response Protein 3 / Q000235:genetics / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009470:Muscle Spindles / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D009420:Nervous System / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D051381:Rats; D020800:Receptor, Nerve Growth Factor / Q000235:genetics / Q000378:metabolism*; D050436:Regulatory Elements, Transcriptional / Q000235:genetics; D012583:Schwann Cells / Q000166:cytology / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse; C497369:Egr3 protein, mouse; D020800:Receptor, Nerve Growth Factor; D051776:Early Growth Response Protein 3