Structural highlights
Function
[AFK_PHYPO] Has a role in the regulation of microfilament formation. Phosphorylates the actin-fragmin complex on threonine residues, in vitro.[1] [2] [3]
Publication Abstract from PubMed
Coordinated temporal and spatial regulation of the actin cytoskeleton is essential for diverse cellular processes such as cell division, cell motility and the formation and maintenance of specialized structures in differentiated cells. In plasmodia of Physarum polycephalum, the F-actin capping activity of the actin-fragmin complex is regulated by the phosphorylation of actin. This is mediated by a novel type of protein kinase with no sequence homology to eukaryotic-type protein kinases. Here we present the crystal structure of the catalytic domain of the first cloned actin kinase in complex with AMP at 2.9 A resolution. The three-dimensional fold reveals a catalytic module of approximately 160 residues, in common with the eukaryotic protein kinase superfamily, which harbours the nucleotide binding site and the catalytic apparatus in an inter-lobe cleft. Several kinases that share this catalytic module differ in the overall architecture of their substrate recognition domain. The actin-fragmin kinase has acquired a unique flat substrate recognition domain which is supposed to confer stringent substrate specificity.
The crystal structure of the Physarum polycephalum actin-fragmin kinase: an atypical protein kinase with a specialized substrate-binding domain.,Steinbacher S, Hof P, Eichinger L, Schleicher M, Gettemans J, Vandekerckhove J, Huber R, Benz J EMBO J. 1999 Jun 1;18(11):2923-9. PMID:10357805[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Eichinger L, Bomblies L, Vandekerckhove J, Schleicher M, Gettemans J. A novel type of protein kinase phosphorylates actin in the actin-fragmin complex. EMBO J. 1996 Oct 15;15(20):5547-56. PMID:8896448
- ↑ Furuhashi K, Hatano S. Actin kinase: a protein kinase that phosphorylates actin of fragmin-actin complex. J Biochem. 1992 Mar;111(3):366-70. PMID:1587799
- ↑ Furuhashi K, Hatano S, Ando S, Nishizawa K, Inagaki M. Phosphorylation by actin kinase of the pointed end domain on the actin molecule. J Biol Chem. 1992 May 5;267(13):9326-30. PMID:1315751
- ↑ Steinbacher S, Hof P, Eichinger L, Schleicher M, Gettemans J, Vandekerckhove J, Huber R, Benz J. The crystal structure of the Physarum polycephalum actin-fragmin kinase: an atypical protein kinase with a specialized substrate-binding domain. EMBO J. 1999 Jun 1;18(11):2923-9. PMID:10357805 doi:http://dx.doi.org/10.1093/emboj/18.11.2923
