2XTZ

Crystal structure of the G alpha protein AtGPA1 from Arabidopsis thaliana

2XTZ の概要

• エントリーDOI: 10.2210/pdb2xtz/pdb
• 分子名称: GUANINE NUCLEOTIDE-BINDING PROTEIN ALPHA-1 SUBUNIT, MAGNESIUM ION, 5'-GUANOSINE-DIPHOSPHATE-MONOTHIOPHOSPHATE, ... (6 entities in total)
• 機能のキーワード: hydrolase, g-protein signaling, self-activation, ras-like domain
• 由来する生物種: ARABIDOPSIS THALIANA (MOUSE-EAR CRESS)
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 125538.05

構造登録者

Jones, J.C.,Duffy, J.W.,Machius, M.,Temple, B.R.S.,Dohlman, H.G.,Jones, A.M. (登録日: 2010-10-13, 公開日: 2011-02-16, 最終更新日: 2024-11-13)

主引用文献

Jones, J.C.,Duffy, J.W.,Machius, M.,Temple, B.R.S.,Dohlman, H.G.,Jones, A.M.
The Crystal Structure of a Self-Activating G Protein Alpha Subunit Reveals its Distinct Mechanism of Signal Initiation
Sci.Signal., 159:RA8-, 2011

PubMed Abstract: In animals, heterotrimeric guanine nucleotide-binding protein (G protein) signaling is initiated by G protein-coupled receptors (GPCRs), which activate G protein α subunits; however, the plant Arabidopsis thaliana lacks canonical GPCRs, and its G protein α subunit (AtGPA1) is self-activating. To investigate how AtGPA1 becomes activated, we determined its crystal structure. AtGPA1 is structurally similar to animal G protein α subunits, but our crystallographic and biophysical studies revealed that it had distinct properties. Notably, the helical domain of AtGPA1 displayed pronounced intrinsic disorder and a tendency to disengage from the Ras domain of the protein. Domain substitution experiments showed that the helical domain of AtGPA1 was necessary for self-activation and sufficient to confer self-activation to an animal G protein α subunit. These findings reveal the structural basis for a mechanism for G protein activation in Arabidopsis that is distinct from the well-established mechanism found in animals.

PubMed: 21304159
DOI: 10.1126/SCISIGNAL.2001446

実験手法

X-RAY DIFFRACTION (2.34 Å)