title: Selective up-regulation of the growth arrest DNA damage-inducible gene Gadd45 alpha in sensory and motor neurons after peripheral nerve injury.
abstract: The growth arrest and DNA damage-inducible gene 45 alpha (Gadd45a) was one of 240 genes found previously by high density oligonucleotide microarray analysis to be regulated in the rat L4 and L5 dorsal root ganglia 3 days after transection of the sciatic nerve (>four-fold up-regulation). The Gadd45a mRNA expression profile investigated by northern blot, RNase protection assay and in situ hybridization in the rat shows negligible constitutive mRNA levels in embryonic, neonatal or adult intact dorsal root ganglia. Within 24 h of a sciatic nerve injury, a very large induction is found that persists for as long as regeneration of injured fibres is prevented by peripheral nerve ligation. When axons are allowed to regrow following sciatic nerve crush injury, Gadd45a expression is terminated at later time points, when levels of other markers of injury return towards normal. Colocalization with activating transcription factor 3-LI and c-jun mRNA implies that all peripherally injured primary sensory and motor neurons express Gadd45a mRNA. Injury to the central axons of dorsal root ganglion neurons produces only a minimal induction of Gadd45a while peripheral inflammation is without effect. Gadd45a is a specific marker of the presence of peripheral axonal injury in adult primary sensory and motor neurons.
authors.affiliation: Neural Plasticity Research Group, Department of Anaesthesia and Critical Care, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA. befort@igbmc.u-strasbg.fr
authors.forename: Katia
authors.initials: K
authors.lastname: Befort
authors.forename: Laurie
authors.initials: L
authors.lastname: Karchewski
authors.forename: Christopher
authors.initials: C
authors.lastname: Lanoue
authors.forename: Clifford J
authors.initials: CJ
authors.lastname: Woolf
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D019771:Axotomy; D015415:Biomarkers; D015152:Blotting, Northern; D015153:Blotting, Western; D018797:Cell Cycle Proteins; D005727:Ganglia, Spinal / Q000502:physiology*; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D009046:Motor Neurons / Q000502:physiology*; D009416:Nerve Regeneration / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology*; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000502:physiology*; D015854:Up-Regulation; D000097642:GADD45 Proteins
chemical_list: D015415:Biomarkers; D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C499073:Gadd45a protein, rat; D000097642:GADD45 Proteins