InterPro domain: IPR008145

This entry represents a domain found in guanylate kinase ( 2.7.4.8 ) and in L-type calcium channel.

Guanylate kinase ( 2.7.4.8 ) (GK) [ 1 ] catalyzes the ATP-dependent phosphorylation of GMP into GDP. It is essential for recycling GMP and indirectly, cGMP. In prokaryotes (such as Escherichia coli), lower eukaryotes(such as yeast) and in vertebrates, GK is a highly conserved monomeric protein of about 200 amino acids. GK has been shown [ 2 , 3 , 4 ] to be structurally similar to protein A57R (or SalG2R) from various strains of Vaccinia virus.

L-type calcium channnels are formed from different alpha-1 subunit isoforms that determine the pharmacological properties of the channel, since they form the drug binding domain. Other properties, such as gating voltage-dependence, G protein modulation and kinase susceptibility, are influenced by alpha-2, delta and beta subunits.

1. Refined structure of the complex between guanylate kinase and its substrate GMP at 2.0 A resolution. J. Mol. Biol. 224, 1127-41
2. A major palmitoylated membrane protein of human erythrocytes shows homology to yeast guanylate kinase and to the product of a Drosophila tumor suppressor gene. Cell 68, 621-2
3. Purification and sequence determination of guanylate kinase from pig brain. Eur. J. Biochem. 213, 263-9
4. Is the erythrocyte protein p55 a membrane-bound guanylate kinase? Trends Biochem. Sci. 17, 99