3R0H image
Entry Detail
PDB ID:
3R0H
Title:
Structure of INAD PDZ45 in complex with NG2 peptide
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2011-03-08
Release Date:
2011-11-30
Method Details:
Experimental Method:
Resolution:
2.60 Å
R-Value Free:
0.26
R-Value Work:
0.19
R-Value Observed:
0.20
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Inactivation-no-after-potential D protein
Chain IDs:A, C (auth: B), E (auth: C), G (auth: D), I (auth: E), K (auth: F), M (auth: G), O (auth: H)
Chain Length:9
Number of Molecules:8
Biological Source:Drosophila melanogaster
Polymer Type:polypeptide(L)
Description:NG2
Chain IDs:B (auth: a), D (auth: b), F (auth: c), H (auth: d), J (auth: e), L (auth: f), N (auth: g), P (auth: h)
Chain Length:9
Number of Molecules:8
Biological Source:
Primary Citation
The INAD scaffold is a dynamic, redox-regulated modulator of signaling in the Drosophila eye
Cell(Cambridge,Mass.) 145 1088 1101 (2011)
PMID: 21703451 DOI: 10.1016/j.cell.2011.05.015

Abstact

INAD is a scaffolding protein that regulates signaling in Drosophila photoreceptors. One of its PDZ domains, PDZ5, cycles between reduced and oxidized forms in response to light, but it is unclear how light affects its redox potential. Through biochemical and structural studies, we show that the redox potential of PDZ5 is allosterically regulated by its interaction with another INAD domain, PDZ4. Whereas isolated PDZ5 is stable in the oxidized state, formation of a PDZ45 "supramodule" locks PDZ5 in the reduced state by raising the redox potential of its Cys606/Cys645 disulfide bond by ∼330 mV. Acidification, potentially mediated via light and PLCβ-mediated hydrolysis of PIP(2), disrupts the interaction between PDZ4 and PDZ5, leading to PDZ5 oxidation and dissociation from the TRP Ca(2+) channel, a key component of fly visual signaling. These results show that scaffolding proteins can actively modulate the intrinsic redox potentials of their disulfide bonds to exert regulatory roles in signaling.

Legend

Protein

Chemical

Disease

Primary Citation of related structures