Open AccessDifferentperiodgene repeats take ‘turns’ at fine-tuning the circadian clock
Author(s) -
Valeria Guantieri,
Antonietta Pepe,
Mauro Agostino Zordan,
Charalambos P. Kyriacou,
Rodolfo Costa,
Antonio Mario Tamburro
Publication year - 1999
Publication title -
proceedings - royal society. biological sciences/proceedings - royal society. biological sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.342
H-Index - 253
eISSN - 1471-2954
pISSN - 0962-8452
DOI - 10.1098/rspb.1999.0920
Subject(s) - pentapeptide repeat , drosophila melanogaster , period (music) , sequence (biology) , circadian clock , peptide , gene , genetics , biology , circadian rhythm , dipeptide , microbiology and biotechnology , biophysics , chemistry , amino acid , biochemistry , endocrinology , physics , acoustics
The repetitive region of the circadian clock gene period in Drosophila pseudoobscura consists predominantly of a pentapeptide sequence whose consensus is NSGAD. In D. melanogaster, this region is replaced by a dipeptide Thr-Gly repeat, which plays a role in the thermal stability of the circadian phenotype. The Thr-Gly repeat has been shown to form a type II or III beta-turn, whose conformational monomer is (Thr-Gly)3. Here we report, using conformational analyses, that both an NSGAD pentapeptide, and a polymer of the same sequence, form type II beta-turns. Thus two peptide sequences, whose amino-acid composition is very different, nevertheless form the same secondary structure. The implications of these structures for clock function are discussed.