Cloning of Cyc (Bmal1) homolog in Bombyx mori: structural analysis and tissue specific distributions.
Cycle (Bmal1) is one of the circadian clock genes and the key regulator of the circadian system in many organisms, encoding a bHLH-PAS transcription factor. In the present study, we cloned cycle homolog (BmCyc) in Bombyx mori. We performed polymerase chain reaction with degenerated primers deduced from the conserved amino acid sequences of mammalian BMAL1 and Drosophila CYCLE. Then the partial clone obtained was used as a probe for screening a cDNA library constructed from pupal brains of B. mori. BmCyc is 5703 nucleotides long and encodes 700 amino acid residues. The BmCYC has bHLH, PAS A and PAS B domains, and the sequence identities for these domains are 85, 60 and 50%, to Drosophila CYCLE (dCYC) and 69, 58 and 50%, to human BMAL1 (hBMAL1), respectively. The deduced amino acid sequence of BmCYC is 37% identical to that of dCYC and 28% to hBMAL1. Northern blot analysis demonstrates that BmCyc gene was expressed in all the tissues tested, which were head, fat body, silk glands, and midgut. Also no significant day, night time-specific difference in expression of BmCyc gene in the head was detected.
Markova
Elitza P
EP
Division of Molecular Science, Graduate School of Science and Technology, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan. 986d907n@y00.kobe-u.ac.jp
Ueda
Hitoshi
H
Sakamoto
Katsuhiko
K
Oishi
Katsutaka
K
Shimada
Toru
T
Takeda
Makio
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D012831:Bombyx / Q000235:genetics*; D002940:Circadian Rhythm / Q000235:genetics; D003001:Cloning, Molecular; D017124:Conserved Sequence / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015870:Gene Expression; D015723:Gene Library; D019476:Insect Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D018076:DNA, Complementary; D019476:Insect Proteins; D012333:RNA, Messenger; D014157:Transcription Factors