1KJY

Crystal Structure of Human G[alpha]i1 Bound to the GoLoco Motif of RGS14

Summary for 1KJY

• Entry DOI: 10.2210/pdb1kjy/pdb
• Descriptor: GUANINE NUCLEOTIDE-BINDING PROTEIN G(I), ALPHA-1 SUBUNIT, REGULATOR OF G-PROTEIN SIGNALING 14, CESIUM ION, ... (6 entities in total)
• Functional Keywords: protein-peptide complex, signaling protein
• Biological source: Homo sapiens (human); More
• Cellular location: Nucleus (By similarity): P63096; Nucleus: O08773
• Total number of polymer chains: 4
• Total formula weight: 85434.52

Authors

Kimple, R.J.,Kimple, M.E.,Betts, L.,Sondek, J.,Siderovski, D.P. (deposition date: 2001-12-05, release date: 2002-05-08, Last modification date: 2023-08-16)

Primary citation

Kimple, R.J.,Kimple, M.E.,Betts, L.,Sondek, J.,Siderovski, D.P.
Structural determinants for GoLoco-induced inhibition of nucleotide release by Galpha subunits.
Nature, 416:878-881, 2002

PubMed Abstract: Heterotrimeric G-proteins bind to cell-surface receptors and are integral in transmission of signals from outside the cell. Upon activation of the Galpha subunit by binding of GTP, the Galpha and Gbetagamma subunits dissociate and interact with effector proteins for signal transduction. Regulatory proteins with the 19-amino-acid GoLoco motif can bind to Galpha subunits and maintain G-protein subunit dissociation in the absence of Galpha activation. Here we describe the structural determinants of GoLoco activity as revealed by the crystal structure of Galpha(i1) GDP bound to the GoLoco region of the 'regulator of G-protein signalling' protein RGS14. Key contacts are described between the GoLoco motif and Galpha protein, including the extension of GoLoco's highly conserved Asp/Glu-Gln-Arg triad into the nucleotide-binding pocket of Galpha to make direct contact with the GDP alpha- and beta-phosphates. The structural organization of the GoLoco Galpha(i1) complex, when combined with supporting data from domain-swapping experiments, suggests that the Galpha all-helical domain and GoLoco-region carboxy-terminal residues control the specificity of GoLoco Galpha interactions.

PubMed: 11976690
DOI: 10.1038/416878a

Experimental method

X-RAY DIFFRACTION (2.7 Å)