title: Molecular and functional characterization of a Schistosoma bovis annexin: fibrinolytic and anticoagulant activity.
abstract: Annexins belong to an evolutionarily conserved multigene family of proteins expressed throughout the animal and plant kingdoms. Although they are soluble cytosolic proteins that lack signal sequences, they have also been detected in extracellular fluids and have been associated with cell surface membranes, where they could be involved in anti-haemostatic and anti-inflammatory functions. Schistosome annexins have been identified on the parasite's tegument surface and excretory/secretory products, but their functions are still unknown. Here we report the cloning, sequencing, in silico analysis, and functional characterization of a Schistosoma bovis annexin. The predicted protein has typical annexin secondary and tertiary structures. Bioassays with the recombinant protein revealed that the protein is biologically active in vitro, showing fibrinolytic and anticoagulant properties. Finally, the expression of the native protein on the tegument surface of S. bovis schistosomula and adult worms is demonstrated, revealing the possibility of exposure to the host's immune system and thus offering a potential vaccine target for the control of schistosomiasis in ruminants.
authors: Parasitology Laboratory, Instituto de Recursos Naturales y Agrobiología de Salamanca, Cordel de Merinas, 40-52, 37008 Salamanca, Spain.
authors: Eduardo
authors: E
authors: de la Torre-Escudero
authors: Raúl
authors: R
authors: Manzano-Román
authors: Mar
authors: M
authors: Siles-Lucas
authors: Ricardo
authors: R
authors: Pérez-Sánchez
authors: J Carlos
authors: JC
authors: Moyano
authors: Inmaculada
authors: I
authors: Barrera
authors: Ana
authors: A
authors: Oleaga
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017302:Annexins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000925:Anticoagulants / Q000494:pharmacology*; D001777:Blood Coagulation / Q000187:drug effects*; D005343:Fibrinolytic Agents / Q000494:pharmacology*; D020869:Gene Expression Profiling; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010958:Plasminogen / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D012547:Schistosoma / Q000235:genetics* / Q000378:metabolism*; D016415:Sequence Alignment; D012756:Sheep
chemical_list: D017302:Annexins; D000925:Anticoagulants; D005343:Fibrinolytic Agents; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D010958:Plasminogen