title: Complex kinase requirements for Chlamydia trachomatis Tarp phosphorylation.
abstract: Chlamydia trachomatis translocates the effector protein Tarp (translocated actin-recruiting phosphoprotein) into the host cell cytoplasm where it is quickly tyrosine phosphorylated. Abl and Src kinases have been implicated in Tarp phosphorylation; however, we observed that the situation is more complex. Chemical inhibition of Src family kinases confirmed a role for these kinases in Tarp phosphorylation. Infection of Src, Yes, Fyn (SYF)-deficient cells showed a dampened, but incompletely blocked, Tarp phosphorylation. Inhibition of Abl in an SYF background still did not completely block Tarp phosphorylation. Consequently, we tested additional kinases and found that Syk, but not Btk or Jak2, is a potent kinase of Tarp in vitro. Inhibition of Syk in an SYF background further blocked Tarp phosphorylation. Under these conditions, inclusion formation still proceeded normally. These data reveal a highly promiscuous substrate property of Tarp and set the stage for further functional characterization of Tarp phosphorylation during host cell infection.
authors.affiliation: Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany.
authors.forename: Adrian
authors.initials: A
authors.lastname: Mehlitz
authors.forename: Sebastian
authors.initials: S
authors.lastname: Banhart
authors.forename: Simone
authors.initials: S
authors.lastname: Hess
authors.forename: Matthias
authors.initials: M
authors.lastname: Selbach
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Meyer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002690:Chlamydia Infections / Q000201:enzymology* / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D010750:Phosphoproteins; D011494:Protein Kinases