3D72

1.65 Angstrom crystal structure of the Cys71Val variant in the fungal photoreceptor VVD

Summary for 3D72

• Entry DOI: 10.2210/pdb3d72/pdb
• Related: 2PD7 2PD8 2PDR 2PDT
• Descriptor: Vivid PAS protein VVD, FLAVIN-ADENINE DINUCLEOTIDE (3 entities in total)
• Functional Keywords: circadian, photoreceptor, blue-light, lov, pas, vvd, signaling protein
• Biological source: Neurospora crassa
• Total number of polymer chains: 2
• Total formula weight: 35564.09

Authors

Zoltowski, B.D.,Crane, B.R. (deposition date: 2008-05-20, release date: 2008-06-17, Last modification date: 2023-08-30)

Primary citation

Zoltowski, B.D.,Crane, B.R.
Light activation of the LOV protein vivid generates a rapidly exchanging dimer.
Biochemistry, 47:7012-7019, 2008

PubMed Abstract: The fungal photoreceptor Vivid (VVD) plays an important role in the adaptation of blue-light responses in Neurospora crassa. VVD, an FAD-binding LOV (light, oxygen, voltage) protein, couples light-induced cysteinyl adduct formation at the flavin ring to conformational changes in the N-terminal cap (Ncap) of the VVD PAS domain. Size-exclusion chromatography (SEC), equilibrium ultracentrifugation, and static and dynamic light scattering show that these conformational changes generate a rapidly exchanging VVD dimer, with an expanded hydrodynamic radius. A three-residue N-terminal beta-turn that assumes two different conformations in a crystal structure of a VVD C71V variant is essential for light-state dimerization. Residue substitutions at a critical hinge between the Ncap and PAS core can inhibit or enhance dimerization, whereas a Tyr to Trp substitution at the Ncap-PAS interface stabilizes the light-state dimer. Cross-linking through engineered disulfides indicates that the light-state dimer differs considerably from the dark-state dimer found in VVD crystal structures. These results verify the role of Ncap conformational changes in gating the photic response of N. crassa and indicate that LOV-LOV homo- or heterodimerization may be a mechanism for regulating light-activated gene expression.

PubMed: 18553928
DOI: 10.1021/bi8007017

Experimental method

X-RAY DIFFRACTION (1.65 Å)