3lmi

From Proteopedia

Crystal Structure of the Inactive Alpha-kinase Domain of Myosin Heavy Chain Kinase A (D766A) complex with ATP

Structural highlights

3lmi is a 4 chain structure with sequence from Dictyostelium discoideum. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.2Å
Ligands:	, , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

MHCKA_DICDI Phosphorylates threonine in the C-terminal tail region of myosin II heavy chain. This phosphorylation is critical in regulating the assembly and disassembly of myosin II filament. Requires autophosphorylation for activity.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Dictyostelium discoideum myosin II heavy chain kinase A (MHCK A) disrupts the assembly and cellular activity of bipolar filaments of myosin II by phosphorylating sites within its alpha-helical, coiled-coil tail. MHCK A is a member of the atypical alpha-kinase family of serine and threonine protein kinases and displays no sequence homology to typical eukaryotic protein kinases. We report the crystal structure of the alpha-kinase domain (A-CAT) of MHCK A. When crystallized in the presence of adenosine triphosphate (ATP), A-CAT contained adenosine monophosphate (AMP) at the active site. However, when crystallized in the presence of ATP and a peptide substrate, which does not appear in the structure, adenosine diphosphate (ADP) was found at the active site and an invariant aspartic acid residue (Asp(766)) at the active site was phosphorylated. The aspartylphosphate group was exposed to the solvent within an active-site pocket that might function as a docking site for substrates. Access to the aspartylphosphate was regulated by a conformational switch in a loop that bound to a magnesium ion (Mg(2+)), providing a mechanism that allows alpha-kinases to sense and respond to local changes in Mg(2+).

Crystal structure of the alpha-kinase domain of Dictyostelium myosin heavy chain kinase A.,Ye Q, Crawley SW, Yang Y, Cote GP, Jia Z Sci Signal. 2010 Mar 2;3(111):ra17. PMID:20197546^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Ye Q, Crawley SW, Yang Y, Cote GP, Jia Z. Crystal structure of the alpha-kinase domain of Dictyostelium myosin heavy chain kinase A. Sci Signal. 2010 Mar 2;3(111):ra17. PMID:20197546 doi:3/111/ra17