Molecular analysis of mammalian timeless.
We cloned the mouse cDNA of a mammalian homolog of the Drosophila timeless (tim) gene and designated it mTim. The mTim protein shows five homologous regions with Drosophila TIM. mTim is weakly expressed in the suprachiasmatic nuclei (SCN) but exhibits robust expression in the hypophyseal pars tuberalis (PT). mTim RNA levels do not oscillate in the SCN nor are they acutely altered by light exposure during subjective night. mTim RNA is expressed at low levels in several peripheral tissues, including eyes, and is heavily expressed in spleen and testis. Yeast two-hybrid assays revealed an array of interactions between the various mPER proteins but no mPER-mTIM interactions. The data suggest that PER-PER interactions have replaced the function of PER-TIM dimers in the molecular workings of the mammalian circadian clock.
Zylka
M J
MJ
Laboratory of Developmental Chronobiology, Pediatric Service, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA.
Shearman
L P
LP
Levine
J D
JD
Jin
X
X
Weaver
D R
DR
Reppert
S M
SM
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D019281:Dimerization; D029721:Drosophila Proteins; D015870:Gene Expression; D019476:Insect Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D009928:Organ Specificity; D056950:Period Circadian Proteins; D011485:Protein Binding; D013493:Suprachiasmatic Nucleus / Q000737:chemistry
D029721:Drosophila Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; C096445:tim protein, Drosophila