Molecular structure, expression patterns, and localization of the circadian transcription modulator CYCLE in the cricket, Dianemobius nigrofasciatus.
CYCLE (CYC), also known as BMAL1 in vertebrate nomenclature, is a transcription modulator of the circadian genes period and timeless of Drosophila melanogaster. We cloned a cDNA encoding a CYC homologue from the head of the ground cricket, Dianemobius nigrofasciatus (Dncyc), the first CYC from Hemimetabola. The deduced sequence corresponded to a 601 amino-acid polypeptide, with well-defined bHLH, PAS-A, PAS-B, PAC, and BTCR domains. The amino-acid sequence showed 70.7% identity with the CYC protein of Athalia rosae, 63.8% with D. melanogaster, and 52% identity with the human homologue. A cyc transcript of around 3.6kb occurs in the brain, midgut, testis, fatbody, and muscle. An additional band of around 1.1kb gave a hybridization signal in the head. No temporal oscillation in cyc mRNA abundance was observed in the head of the adult cricket when investigated by Northern blot analysis. CYC-like immunohistochemical reactivity (ir) and its dimerization partner CLOCK (CLK)-ir appeared in the pars intercerebralis (PI), tritocerebrum, dorsolateral protocerebrum, and subesophageal ganglion (SOG), but no CYC-ir was observed in the optic lobe (OL) that showed CLK-ir. The deutocerebrum showed a unique CLK-ir but no CYC-ir pattern. Double-labelling experiments showed that both antigens were co-localized in the mandibular and maxillary neuromeres of the SOG. CYC-ir showed no daily oscillation in intensity and the staining pattern was always cytoplasmic. CLK-ir occurred in the nucleus at ZT 16, but was cytoplasmic at other ZT times. A neuronal network equivalent to adult system occurred in the second nymphal stadium.
Shao
Qi-Miao
QM
Division of Molecular Science, Graduate School of Science and Technology, Kobe University, Kobe, Japan.
Bembenek
Jadwiga
J
Trang
Le Thi Dieu
le TD
Hiragaki
Susumu
S
Takeda
Makio
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D002940:Circadian Rhythm / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D006135:Gryllidae / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D011487:Protein Conformation; D021381:Protein Transport; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D019476:Insect Proteins; D014157:Transcription Factors