ABSTRACT
Here we describe the cloning and characterization of the Schistosoma mansoni Alkaline Phosphatase (SmAP), previously identified in the tegument of adult worms. SmAP encodes a complete sequence composed of 536 amino acids containing an N-terminal signal peptide, five N-glycosylation sites, and a GPI anchor signal, similar to that described for mammalian orthologs. Real-time RT-PCR and Western blot experiments suggest a rapid translation as soon as cercariae are transformed into schistosomula. Immunolocalization analysis shows that the protein is widely distributed in the worm tissues, with increased concentration in the vitelline glands of female parasites. Furthermore, the surface localization of this enzyme was quantitatively supported by its enzymatic activity in live ex vivo or cultured parasites throughout the life cycle stages. The fact that cercariae accumulate large amounts of SmAP mRNA, which rapidly translates into protein upon schistosomula transformation, indicates it may have an important role in host invasion.
Subject(s)
Alkaline Phosphatase/genetics , Gene Expression Regulation, Enzymologic , Schistosoma mansoni/enzymology , Alkaline Phosphatase/chemistry , Alkaline Phosphatase/metabolism , Animals , Base Sequence , Blotting, Western , Cricetinae , DNA, Complementary/chemistry , DNA, Helminth/chemistry , Female , Life Cycle Stages/genetics , Male , Microscopy, Confocal , Microscopy, Fluorescence , Real-Time Polymerase Chain Reaction , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Schistosoma mansoni/genetics , Schistosoma mansoni/growth & development , Sequence Alignment , Transcription, GeneticABSTRACT
Here we describe the cloning and characterization of the Schistosoma mansoni Alkaline Phosphatase(SmAP), previously identified in the tegument of adult worms. SmAP encodes a complete sequence composedof 536 amino acids containing an N-terminal signal peptide, five N-glycosylation sites, and a GPIanchor signal, similar to that described for mammalian orthologs. Real-time RT-PCR and Western blotexperiments suggest a rapid translation as soon as cercariae are transformed into schistosomula. Immunolocalizationanalysis shows that the protein is widely distributed in the worm tissues, with increased concentration in the vitelline glands of female parasites. Furthermore, the surface localization of thisenzyme was quantitatively supported by its enzymatic activity in live ex vivo or cultured parasites throughout the life cycle stages. The fact that cercariae accumulate large amounts of SmAP mRNA, which rapidly translates into protein upon schistosomula transformation, indicates it may have an important role in host invasion.
