Abstrakt: |
Two monoclonal antibodies (Gc3.2 and Bd 2.2) against surface components of the cnidocil complex of Hydra vulgaris have been produced. In indirect immunofluorescence and in immunogold-labelling, the Gc 3.2-antibody stains the complete surface of all nematocytes, whereas other cellular surfaces are not labelled. The Bd 2.2-antibody, in contrast, produces only a small band of fluorescence on isolated cnidocils. This pattern of fluorescence and the corresponding immunogold-labelling indicate that the Bd 2.2-antibody exclusively binds to those intermembrane connectors that link the cnidocil and stereovillar cone in situ. In isolated and decnidociliated nematocytes, the tips of the stereovilli are also labelled by the Bd 2.2-antibody. Physiological experiments suggest that the Bd 2.2-antibody disturbs the reconstitution of intermembrane connectors during cnidocil regeneration. These data confirm the hypothesis that the intermembrane connectors are formed by two identical subunits located at the cnidociliar and stereovillar surfaces. |