Email updates

Keep up to date with the latest news and content from BMC Molecular Biology and BioMed Central.

Open Access Highly Accessed Research article

Identification of two Amino Acids in the C-terminal Domain of Mouse CRY2 Essential for PER2 Interaction

Natali Ozber1, Ibrahim Baris2, Gulnaz Tatlici2, Ibrahim Gur2, Seda Kilinc3, Evrim B Unal3 and Ibrahim H Kavakli123*

Author Affiliations

1 Material Science and Engineering, College of Engineering, Koc University, Rumeli Feneri Yolu, 34450 Sariyer, Istanbul, Turkey

2 Department of Chemical and Biological Engineering, College of Engineering, Koc University, Rumeli Feneri Yolu, 34450 Sariyer, Istanbul, Turkey

3 Centre for Computational Biology and Bioinformatics, College of Engineering, Koc University, Rumeli Feneri Yolu, 34450 Sariyer, Istanbul, Turkey

For all author emails, please log on.

BMC Molecular Biology 2010, 11:69  doi:10.1186/1471-2199-11-69

Published: 14 September 2010

Abstract

Background

Cryptochromes (CRYs) are a class of flavoprotein blue-light signaling receptors found in plants and animals, and they control plant development and the entrainment of circadian rhythms. They also act as integral parts of the central circadian oscillator in humans and other animals. In mammals, the CLOCK-BMAL1 heterodimer activates transcription of the Per and Cry genes as well as clock-regulated genes. The PER2 proteins interact with CRY and CKI╬Á, and the resulting ternary complexes translocate into the nucleus, where they negatively regulate the transcription of Per and Cry core clock genes and other clock-regulated output genes. Recent studies have indicated that the extended C-termini of the mammalian CRYs, as compared to photolyase proteins, interact with PER proteins.

Results

We identified a region on mCRY2 (between residues 493 and 512) responsible for direct physical interaction with mPER2 by mammalian two-hybrid and co-immunoprecipitation assays. Moreover, using oligonucleotide-based degenerate PCR, we discovered that mutation of Arg-501 and Lys-503 of mCRY2 within this C-terminal region totally abolishes interaction with PER2.

Conclusions

Our results identify mCRY2 amino acid residues that interact with the mPER2 binding region and suggest the potential for rational drug design to inhibit CRYs for specific therapeutic approaches.