title: Haemonchus contortus: prokaryotic expression and enzyme activity of recombinant HcSTK, a serine/threonine protein kinase.
abstract: Members of the PAR-1/MARK serine/threonine protein kinase (STK) subfamily are important regulators of the cytoskeleton, and their characterization can provide insights into a number of critical processes relating to the development and survival of an organism. We previously investigated the mRNA expression for and organization of a gene (hcstk) representing HcSTK, an STK from the parasitic nematode Haemonchus contortus. In the present study, a recombinant form of HcSTK was expressed and characterized. Affinity-purified anti-HcSTK antibodies reacted with native HcSTK in protein homogenates extracted from third-stage larvae (L3) of H. contortus and were also used to immunolocalize the protein around the nuclei of ovarian and intestinal tissues of adult H. contortus. The enzyme activity of the recombinant HcSTK protein was also demonstrated. The findings show that recombinant HcSTK is a functional protein kinase, with activity directed to KXGS motifs, consistent with other members of the PAR-1/MARK STK subfamily.
authors.affiliation: Primary Industries Research Victoria (Animal Genetics and Genomics), 475 Mickleham Road, Attwood, Vic. 3049, Australia.
authors.forename: Sia
authors.initials: S
authors.lastname: Nikolaou
authors.forename: Dadna
authors.initials: D
authors.lastname: Hartman
authors.forename: Alasdair J
authors.initials: AJ
authors.lastname: Nisbet
authors.forename: Robin B
authors.initials: RB
authors.lastname: Gasser
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000096:biosynthesis / Q000276:immunology / Q000302:isolation & purification; D015153:Blotting, Western; D002846:Chromatography, Affinity; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006189:Haemonchus / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D007106:Immune Sera / Q000096:biosynthesis / Q000276:immunology / Q000302:isolation & purification; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012756:Sheep
chemical_list: D000909:Antibodies, Helminth; D007106:Immune Sera; D012333:RNA, Messenger; D011994:Recombinant Proteins; D017346:Protein Serine-Threonine Kinases