Mitogen-activated protein kinase phosphatase-1 in olfactory neural regeneration.
Uniquely, olfactory neurons continuously replace themselves. Olfactory bulb ablation induces coordinated degeneration and regeneration in olfactory neuroepithelium; up-regulated growth factors bind to their receptors, initiating a phosphorylation cascade activating mitogen-activated protein kinases (MAPK). MAPK then relay proliferation signals to the nucleus. Mitogen-activated protein kinase phosphatase-1 (MKP-1) inactivates MAPK. We examined MKP-1 expression in adult mouse olfactory epithelium following bulbectomy using a reverse transcription-polymerase chain reaction (RT-PCR) as well as Western analysis. While MKP-1 expression was high in olfactory epithelium from control mice, it decreased greatly 2-3 weeks after bulbectomy in temporal association with increased tyrosine phosphorylation of MAPK. Thus, reduced MKP-1 expression may contribute to regeneration of olfactory neuroepithelium after bulbectomy via decreased dephosphorylation of MAPK.
Shinogami
M
M
Department of Otolaryngology, University of Tokyo, Japan.
Ishibashi
T
T
D000818:Animals; D015153:Blotting, Western; D018797:Cell Cycle Proteins; D017931:DNA Primers; D054638:Dual Specificity Phosphatase 1; D004789:Enzyme Activation / Q000502:physiology; D004848:Epithelium / Q000378:metabolism; D017874:Immediate-Early Proteins / Q000502:physiology*; D051379:Mice; D009416:Nerve Regeneration / Q000502:physiology*; D009830:Olfactory Bulb / Q000201:enzymology* / Q000502:physiology*; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018797:Cell Cycle Proteins; D017931:DNA Primers; D017874:Immediate-Early Proteins; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054638:Dual Specificity Phosphatase 1; C517020:Dusp1 protein, mouse; D017027:Protein Tyrosine Phosphatases