Crystal structure and interactions of the PAS repeat region of the Drosophila clock protein PERIOD.

Ozkan Yildiz , Masao Doi (1) , Irene Yujnovsky (1) , Luca Cardone (1) , Alex Berndt , Sven Hennig , Sabrina Schulze , Claus Urbanke , Paolo Sassone-Corsi (1) , Eva Wolf

1 IGBMC - Institut de génétique et biologie moléculaire et cellulaire

PERIOD proteins are central components of the Drosophila and mammalian circadian clock. Their function is controlled by daily changes in synthesis, cellular localization, phosphorylation, degradation, as well as specific interactions with other clock components. Here we present the crystal structure of a Drosophila PERIOD (dPER) fragment comprising two tandemly organized PAS (PER-ARNT-SIM) domains (PAS-A and PAS-B) and two additional C-terminal alpha helices (alphaE and alphaF). Our analysis reveals a noncrystallographic dPER dimer mediated by intermolecular interactions of PAS-A with PAS-B and helix alphaF. We show that alphaF is essential for dPER homodimerization and that the PAS-A-alphaF interaction plays a crucial role in dPER clock function, as it is affected by the 29 hr long-period perL mutation.

Domaines: Biologie moléculaire

Ozkan Yildiz, Masao Doi, Irene Yujnovsky, Luca Cardone, Alex Berndt, et al.. Crystal structure and interactions of the PAS repeat region of the Drosophila clock protein PERIOD.. Molecular Cell, 2005, 17 (1), pp.69-82. ⟨10.1016/j.molcel.2004.11.022⟩. ⟨hal-00187803⟩