Identification of dual specificity phosphatases induced by olfactory bulbectomy in rat olfactory neuroepithelium.
Dual specificity protein tyrosine phosphatases (dsPTPs) are a subfamily of protein tyrosine phosphatases implicated in the regulation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK), and p38 mitogen-activated protein kinases (MAPKs) which are target enzymes activated by a wide range of cell-surface stimuli. Like these kinases, a class of dsPTP has been implicated in cell differentiation, regeneration, and apoptosis. In order to isolate dsPTPs which might play an important role in neuronal regeneration and apoptosis in olfactory neuroepithelium, we subcloned DNA fragments amplified by reverse transcription-polymerase chain reaction (RT-PCR), using degenerate oligonucleotide primers based on the conserved amino acid regions within the catalytic domain of dsPTPs, from rat olfactory epithelial RNA 1 and 4 h after an olfactory bulbectomy. The PCR products were subcloned into the pCRII vector, and 23 clones were chosen for further characterization. The sequence of these 23 individual clones revealed that two clones were identical to the rat dsPTP, MKP-3, and the other 21 clones were identical to the rat dsPTP, MKP-1. By Northern analysis, the MKP-1 transcript was induced and peaked 4 h following a bulbectomy. Similar results were obtained with the MKP-3 transcript. These results suggest that MKP-1 and MKP-3 may be involved in the early steps of apoptosis in vivo in rat olfactory neuroepithelium.
Ishibashi
T
T
Department of Otolaryngology, Social Insurance Central General Hospital, 3-22-1, Hyakunincho, Shinnjuku-ku, 169-0073, Tokyo, Japan. tisibasi-oto@umin.ac.jp
Shinogami
M
M
Ishimoto
S
S
Nibu
K
K
Suzuki
M
M
Kaga
K
K
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D019771:Axotomy; D001483:Base Sequence; D015152:Blotting, Northern; D018797:Cell Cycle Proteins; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D054638:Dual Specificity Phosphatase 1; D054642:Dual Specificity Phosphatase 6; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D017874:Immediate-Early Proteins / Q000235:genetics; D020935:MAP Kinase Signaling System / Q000502:physiology*; D008297:Male; D009410:Nerve Degeneration / Q000201:enzymology* / Q000503:physiopathology; D009830:Olfactory Bulb / Q000601:surgery; D009831:Olfactory Mucosa / Q000166:cytology / Q000201:enzymology*; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D017874:Immediate-Early Proteins; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054638:Dual Specificity Phosphatase 1; D054642:Dual Specificity Phosphatase 6; C517021:Dusp1 protein, rat; C517037:Dusp6 protein, rat; D017027:Protein Tyrosine Phosphatases