Cytoskeleton-membrane interactions in the cnidocil complex of hydrozoan nematocytes

摘要: Each cnidocil complex of the hydrozoans Tubularia larynx and Hydra vulgaris consists 9 or 7–10 large stereovilli (=stereocilia), respectively, a modified cilium, cnidocil. The cnidocils comprise regular microtubule doublets, up to 30 additional microtubules, as well central filament body. Adjacent are linked together by intermembrane connectors forming stereovillar cone. distal tips surround in closed tubular arrangement measuring 0.7 μm length. Within this contact region is tube another set connectors, which seem hold position within Stereovillar membrane actin core 16-nm long cross bridges, display periodicity 16 nm emerge from core. periodically arranged membrane-cytoskeleton bridges uniformly restricted region. Here, 24-nm spaced distance 20 nm, interconnect A-tubules doublets membrane. cnidociliary differentiated into distinct domains revealed freeze-fracturing. nematocytes larynx, intramembrane particles rows 700 length 50 width, separated particlefree areas. Intramembrane irregularly distributed Considering recent physiological results we presume that latter represent chemoreceptor units, while mechanical stimuli transmitted via microtubule-membrane mechanosensitive channels domain