THE SCHISTOSOMA-MANSONI EPIDERMAL GROWTH-FACTOR RECEPTOR HOMOLOG, SER, HAS TYROSINE KINASE-ACTIVITY AND IS LOCALIZED IN ADULT MUSCLE

DNA encoding the full-length Schistosoma mansoni epidermal growth fact or receptor, SER, was obtained by combining partial cDNA clones. Three different anti-SER antibody preparations, specific either to the SER amino-terminus or the predicted ligand binding domain were generated w ith recombinant or synthetic peptides and purified by antigen affinity . Recombinant SER was expressed within insect cells using the baculovi rus expression system and detected by each of the anti-SER antibodies as well as anti-phosphotyrosine antibodies. By in vitro phosphorylatio n of immunoprecipitated recombinant SER, the protein has been shown to be capable of tyrosine autophosphorylation but this activity is not a ffected by human epidermal growth factor. Native SER is detected as a 170 kDa protein in Western blots of S. mansoni adult worm membrane pre parations. Adult worm sections, labeled with anti-SER antibodies, loca lize SER predominantly to the muscle of adult male and female worms. T hese results confirm a place for SER in the EGFR family of tyrosine ki nases and strongly suggest that it participates in schistosome signal transduction, perhaps related to muscle development or function. Copyr ight (C) 1996 Elsevier Science B.V.