title: Cloning and circadian expression of rat Cry1.
abstract: In mammals, two types of cryptochrome are involved in the regulation of the circadian rhythm. We previously characterized rat Cry2 and its expression in brain tissue [Eun et al. (2001)]. We report here the cloning of another cryptochrome gene, Cry1, from rat brain by reverse-transcription coupled to polymerase chain reaction (RT-PCR), together with rapid-amplification of cDNA ends (RACE). The cloned Cry1 cDNA consists of 2557 nucleotides and has a single open-reading frame encoding a protein of 588 amino acids with start and stop codons. The deduced amino acid sequence was 70% identical with that of rat Cry2. It also showed 95% identity with mouse and human Cry1 but relatively low identity of 82% with that of zebrafish. Circadian expression of rat Cry1 and Cry2 was examined in the suprachiasma nucleus (SCN) and eye by real-time PCR. Expression of Cry1 and Cry2 mRNA in the SCN displayed a circadian rhythm with a peak at the day/night transition, and there was a slightly different circadian pattern of expression of Cry1 and Cry2 in the eye.
authors.affiliation: Department of Genetic Engineering, Cheongju University, Cheongju 360-764, Korea.
authors.forename: Kyungbae
authors.initials: K
authors.lastname: Park
authors.forename: Hae Mook
authors.initials: HM
authors.lastname: Kang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001923:Brain Chemistry; D002940:Circadian Rhythm; D003001:Cloning, Molecular / Q000379:methods*; D056931:Cryptochromes; D005123:Eye / Q000737:chemistry; D005420:Flavoproteins / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D017421:Sequence Analysis; D012689:Sequence Homology, Nucleic Acid; D013493:Suprachiasmatic Nucleus / Q000737:chemistry
chemical_list: C538963:CRY1 protein, human; C538966:CRY2 protein, human; C538964:Cry1 protein, mouse; C538965:Cry1 protein, rat; C538967:Cry2 protein, mouse; C538968:Cry2 protein, rat; D056931:Cryptochromes; D005420:Flavoproteins