A new haemagglutinin from the amoebocytes of the horseshoe crab Carcinoscorpius rotundicauda. Purification and role in cellular aggregation.
The present paper describes the purification and function of a haemagglutinin from the amoebocyte lysate of the horseshoe crab Carcinoscorpius rotundicauda. The purified protein consisted of a single subunit of Mr 24 000 and agglutinated human blood-group-A+ erythrocytes. Its haemagglutinin activity was inhibited by purified lysate, coagulogen, but not by sugars. The haemagglutinin differed immunologically and in activity from the sialic-acid-binding lectin carcinoscorpin present in the haemolymph. It caused aggregation of forma-fixed amoebocytes, and on the basis of this observation its role in cell-cell adhesion is proposed. This new haemagglutinin promotes cell-cell aggregation in amoebocytes in a manner that shares some similarities with thrombospondin-mediated platelet aggregation in vertebrates [Jaffe, Leuang, Nachman, Levin & Moseher (1981) Nature (London) 295, 246-248].
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D003386:Brachyura / Q000166:cytology; D002449:Cell Aggregation / Q000187:drug effects; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004903:Erythrocyte Aggregation / Q000187:drug effects; D006388:Hemagglutinins / Q000302:isolation & purification* / Q000494:pharmacology; D006737:Horseshoe Crabs / Q000378:metabolism*; D008858:Microscopy, Phase-Contrast; D013056:Spectrophotometry, Ultraviolet
D000596:Amino Acids; D006388:Hemagglutinins