Molecular characterization and nuclear localization of rat timeless-like gene product.
Among three period genes (per1, per2, per3) in mammals, only per2 gene was shown to be involved in the core clock mechanism. To elucidate the molecular function of rat PERIOD2 (rPER2), we searched for binding proteins to the PAS domain of rPER2. We isolated a binding protein to this domain and identified it as a TIMELESS-like protein (TLP) on the basis of mass analyses. Then, we isolated a rat TLP cDNA from the rat hypothalamus library. RNA blot analysis and in situ hybridization indicates that rTLP mRNA was expressed in all rat tissues from whole brain, the suprachiasmatic nucleus, eye, lung, heart, liver, kidney, placenta, and testis. When rTLP gene product was expressed in COS-1 cells, nuclear localization of rTLP was detected in 99.6% of transfected cells. These results suggest that the interaction of rPER2 with rTLP may influence the regulation of circadian clock components in nucleus after rPER2 is translocated into the nucleus.
Sakamoto
S
S
Laboratory of Molecular Biology, Medical Research Center, Kochi Medical School, Okoh, Nankoku, Kochi 783-8505, Japan.
Miyazaki
K
K
Fukui
H
H
Oishi
K
K
Hayasaka
N
N
Okada
M
M
Kamakura
M
M
Taniguchi
T
T
Nagai
K
K
Ishida
N
N
D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002417:Cattle; D018797:Cell Cycle Proteins; D002467:Cell Nucleus / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D029721:Drosophila Proteins; D006801:Humans; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D056950:Period Circadian Proteins; D051381:Rats; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors
D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D029721:Drosophila Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; C421902:PER2 protein, human; C513311:Per2 protein, rat; D056950:Period Circadian Proteins; D014157:Transcription Factors; C096445:tim protein, Drosophila