EDInfo Biomedical Sciences Maciver Lab. Home ABP  A-Z Encyclopaedia Amoebae Protist Links Cytoskeleton Links Site Index

YpkA (YopO)

A serine/threonine kinase from Yersinia that binds and is activated by actin when secreted into eukaryote cells by type III secretion mechanism (Juris et al, 2000).  Both G and F-actin and G-actin bound to DNase1 are able to activate the kinase.  The C-terminus of the kinase is responsible for actin binding and bacteria lacking this part of the gene are not virulent (Galyov et al, 1993).  A region in the C-terminus has reputed homolgy to the ABP coronin. Actin is one of the substrates for the kinase, and cells transfected with the kniase have a disrupted actin cytoskeleton and round up.  YpkA is not alone in phosphorylating actin (see actin kinases).


Galyov, E.E., Hakannsson, S., Forsberg, A. & Wolf-Watz, H  (1993). "" Nature 361, 730-732.

Juris, S.J., Rudolph, A.E., Huddler, D., Orth, K., & Dixon, J.E. (2000). "A distinctive role for the Yersinia protein kinase: Actin binding, kinase activation, and cytoskeleton disruption." PNAS 97(17); 9431-9436.

Related topics within this site:-

Actin kinases
Bacterial invasion of cells and the actin cytoskeleton.


  EDInfo Biomedical Sciences Cytoskeletal Links Encyclopaedia of A.B.P.s The Amoebae Protozoology links Glossary of Amoeba terms   Maciver Lab Home