A novel TRH-PFTAIRE protein kinase 1 pathway in the cerebellum: subtractive hybridization analysis of TRH-deficient mice.
TRH has been reported to possess several neurophysiological actions in the brain. To gain insights into the molecular mechanisms underlying these effects, particularly in the cerebellum, we attempted to clone a cDNA that was regulated by TRH using TRH knockout mice and subtractive cDNA analysis. Over 100 clones obtained by subtractive hybridization analysis between the wild-type and TRH-1-cerebellum were analyzed. Four clones among them were identical and cdc2-related kinase (PFTAIRE protein kinase 1 (PFTK1)) cDNA, which was previously reported to be expressed only in the brain and testis. PFTK1 mRNA levels in the euthyroid TRH-1- cerebellum supplemented with thyroid hormone were significantly decreased compared with those in the wild-type. Induction of PFTK1 mRNA by TRH was also observed in a time- and dose-dependent manner in human medulloblastoma-derived HTB-185 cells that expressed TRH receptor subtype I mRNA. In addition, treatment of 8-Br-cGMP significantly increased PFTK1 mRNA levels, and a specific inhibitor of cGMP production, ODQ, completely blocked TRH-induced expression of PFTK1 mRNA. Furthermore, induction of PFrK1 mRNA by TRH was significantly inhibited by a NOS specific inhibitor, L-NAME, but not by a MEK inhibitor, PD98059 or a calcium channel inhibitor, nimodipine. These findings demonstrated, for the first time, a novel pathway between a neuropeptide and a cell cycle related peptide in the brain, and PFTK1 may be a key regulator for TRH action in t he cerebellum through t he NO-cGMP pathway.
Hashida
Tetsu
T
First Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Japan.
Yamada
Masanobu
M
Hashimoto
Koshi
K
Shibusawa
Nobuyuki
N
Monden
Tsuyoushi
T
Satoh
Teturou
T
Mori
Masatomo
M
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D015152:Blotting, Northern; D002478:Cells, Cultured; D002531:Cerebellum / Q000502:physiology*; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000096:biosynthesis / Q000494:pharmacology; D018844:Cyclin-Dependent Kinases; D029721:Drosophila Proteins; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D011494:Protein Kinases / Q000235:genetics* / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013973:Thyrotropin-Releasing Hormone / Q000172:deficiency / Q000235:genetics* / Q000502:physiology*; D014157:Transcription Factors; D014407:Tumor Cells, Cultured
D029721:Drosophila Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D013973:Thyrotropin-Releasing Hormone; D000242:Cyclic AMP; D011494:Protein Kinases; D018844:Cyclin-Dependent Kinases; C408322:Eip63E protein, Drosophila