| The ultrastructure , protein composition and cytoskeleton of Stylonychia mytilus in Hypotrich ciliate were detemined by use of sanning electron microscopy (SEM), transmission electron microscopy (TEM), as well as immuno-electron Microscopy. The result is as follows:1 A SEM observation on morphogenesis of the cortical ciliaturesThe cortical ciliatures of the Stylonychia mytilus consisted of adoral zone of membranelles (AZM), undulating membranes(UM), frontal-ventral-transverse cirri(FVTC), left and right-marginal cirri(L/RMC), dorsal kineties(DK) and so on. During the asexual division of Stylonychia mytilus , holes were observed on the surface of cell pellicle in the anlagen region by using scanning electron microscope. Then, cilia buds extend from each hole and form the anlagen region of new ciliatures; 1/3 part of the old adoral zone of membranelles (AZM) was renewed, together with the leftever constitute an intact AZM at the original area which belonged to the proter; The new marginal cirri primordium presents in the front and the middle part of the degenerated site of the old marginal cirri, after that, the new marginal cirri formed at the right area but not the originally area of the old ones.These results show that during the process of morphogenesis, the basal bodies form below the surface of cell pellicle; the constitution of AZM in the proter is related to the renewal of the old AZM, the old cilias which belong to the anlagen region played an important part in the location and orientation of the new structure, what's more , supplied its development with some substances. This paper described the details integratly on morphogenesis of Stylonychia mytilus and the results could provide some new references for a better understanding of the structure as well as the tions of microtubular cytoskeletons in ciliates.2 A TEM observation on ultrastructure of the cortical microtubular cytoskeleton duringasexual divisionsThe microtubular cytoskeleton of the Stylonychia mytilus consists of ciliatures and its base-associated microtubules and other microtubular cytoskeletons in the cortex. Transmission electron microscopy reveals : there are pellicles ,the ciliated basal bodies and their associated structures among them (filament links among basal bodies , the posterior longitudinal and traverse microtubules) at the ciliated regions. Meanwhile, the membranelle-skeleton of AZM formed by the connection of high electron-dense bands with cylindrical fibrous matters; the frontal-ventral cirri skeletons formed by basal body brackets and MT ribbons under basal bodies. There are also longitudinal microtubule layers, the left- and right-microtubular ribbons , the caudal microtubular net at the non-ciliated regions in the cortex.During the morphogenesis, the essential compositions of the all the ciliatures are basal bodies, morevere, the formation and orientation of these basal bodies in the cortex are also revealed.3 The localization of α -tubulin in Stylonychia mytilus by Immuno-electron MicroscopyThis study described a more effective improved method for visualizing the cytoskeleton and special compoment in the cell based on the immune colloidal gold techniques home and abroad . Some main improved steps are incubating cells with saponin, fixing cells with polyformaldehyde and glutaraldehyde, as well as post-embeding method. The gold labeling also appears in the membranelle basal bodies and associated filament among them of AZM , filament links between the basal bodies, cilias and so on. The result show that these structures are microtubule organelles composed of tubulins. This established technique is a recruit and improvement to the immunofluorescence and other methods.In a word, these result visualizing the ultrastructure of the Stylonychia mytilus during asexual divisions by SEM and TEM are consistent with the result by immuno-electron microscopy. All these statement provide some datas for a better understanding for morphogenesis and protein composition of the Stylonychia mytilus .
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