Related Experiment Video
Updated: Sep 2, 2026

Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
Direct activation of guanine nucleotide binding proteins through a high-energy phosphate-transfer by nucleoside
1Department of Bacteriology, Tohoku University School of Medicine, Sendai, Japan.
Abstract:
An in vitro study of phosphate-transfer, from the high-energy phosphates on the phosphoenzyme (enzyme-bound high-energy phosphate intermediate) of NDP-kinase to GDP on various guanine nucleotide binding proteins (G1, elongation factor alpha 1, recombinant v-rasH p21 protein, transducin, Gi and Go), revealed that the GDP acts as a phosphate-acceptor, in the presence of divalent cations (Mg2+ and Ca2+). This finding suggests that via phosphate-transfer, NDP-kinase may be responsible for the direct activation of various guanine nucleotide binding proteins through phosphate-transfer by the enzyme.
Related Concept Videos
GTPases and their Regulation
Large G-proteins, also known...
Amplifying Signals via Enzymatic Cascade
Activation and Inactivation of G Proteins
GPCRs Regulate Adenylyl Cylase Activity
Two...
cAMP-dependent Protein Kinase Pathways
IP3/DAG Signaling Pathway

