A LECTIN-LIKE MOLECULE IS DISCHARGED FROM MUCOCYSTS OF TETRAHYMENA-PYRIFORMIS IN THE PRESENCE OF INSULIN

By use of a monoclonal antibody directed against purified lectin from the sponge Geodia cydonium it was demonstrated that the mucocysts of T etrahymena pyriformis contain a substance immunologically similar to t hat found in G. cydonium. In extracts of T. pyriformis the monoclonal antibody recognizes a 36 kDa protein; binding could be abolished by ad sorption of the antibody with (i) crude extract, (ii) purified lectin from G. cydonium and (iii) a 29 aa longpeptide. In addition the data s how that 10(-6) M of insulin causes first the release of mucocyst mate rial, which reacts with the lectin antibody, and second its subsequent redistribution on the surface of the somatic cilia and the oral field .