Right before the excystment of an Euplotes encysti-cus sawtooth-like folds appeared among the pellicle plas- malemma, the inner and outer alveolar membranes were still sticking together, and were not distinguishable. ...Right before the excystment of an Euplotes encysti-cus sawtooth-like folds appeared among the pellicle plas- malemma, the inner and outer alveolar membranes were still sticking together, and were not distinguishable. Mi- crotubular layers already formed at the sites beneath the dorsal cortical pellicle corresponding to vegetative cells,but they still proceed to be organized on the ventral struc-tures. Cristae, highly-tangled with tubular-type struc-tures, appeared on the mitochondria, and were morpho-logically similar to that of vegetative cells. In the cor-tical ciliatures, such as ciliary shafts, kinetosomes, sur-rounding fibrillar cirral baskets, and attached structures of ciliatures, etc., they are different from those in rest- ing cysts which are degenerated or lost. All the cilia- ture microtubules of ciliary shafts are of the 9+2 pattern,but the microtubule-like structure aggregates at triplet - microtubule centers of many kinetosmes, are still under various stages of differentiation. Microtubules beneath the kinetosomal rows are of a developmentally elongated stage; crowded chromatins of various shapes and sizes are found in macronucleus, but there are no nuclear pores (formed by nuclear membrane as in resting cysts) on the nuclear membrane where these chromatins attached.展开更多
We examined the structure and spatial organization of ciliature base-associated microtubules (BAM) in three hypotrichous ciliates (Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi) in fluorescence ...We examined the structure and spatial organization of ciliature base-associated microtubules (BAM) in three hypotrichous ciliates (Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi) in fluorescence microscopy. The results revealed that BAM, including the anterior (ALM), posterior longitudinal microtubule (PLM) and the transverse microtubule (TM) bands, are composed of tubulin. The respective microtubular bands have cytoplasmic polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri (MC) in S. rnytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they are directly associated with cell motion.展开更多
The cortical ciliature microtubular organelles of the ciliated protozoan Euplotes Woodruffi were analyzed with FLUTAX and anti-a-tubulin antibody. It showed that the cortical cytoskeleton was composed of non-ciliature...The cortical ciliature microtubular organelles of the ciliated protozoan Euplotes Woodruffi were analyzed with FLUTAX and anti-a-tubulin antibody. It showed that the cortical cytoskeleton was composed of non-ciliature structure, ciliature structure including adoral zone of membranelles (AZM), undulating membranes (UM), frontal-ventral-transverse cirri (FVTC), caudal cirri (CC), dorsal kineties, as well as base-associated microtubules. The silverline system is composed of longitudinal and transverse microtubules, concave structure appeared on the cell dorsal side, the base of DK containing rosette-like skeleton structure. All these suggested that the non-ciliature structure, ciliature structure of Euplotes be quite different from that of other species of ciliate, the silverline-system be true pare of cortical microtubute cytoskeleton in Euplotes, rosette structure be part of the basecytoskeleton.展开更多
The ultrastructure of extrusomes of the hypotrichous ciliate Pseudourostyla nova was observed in scanning and transmission electron microscopy and enzyme-cytochemistry. The results show that the distribution, morpholo...The ultrastructure of extrusomes of the hypotrichous ciliate Pseudourostyla nova was observed in scanning and transmission electron microscopy and enzyme-cytochemistry. The results show that the distribution, morphological characteristics, morphogenesis process, and extrusive process of the extrusomes in P. nova are different from the trichocysts in Paramecium, suggesting that the extrusomes of P. nova can respond to environmental stimuli, play an important role in the defense of this species, and cannot be regarded as "trichocysts". The results also suggest that the extrusomes might be originated from the Golgi apparatus and mature in the cytoplasm; after the extrusion of mature extrusomes, the residual substance might be reabsorbed and reused by the ciliate cell via food vacuoles, and take part in material recycling of the cell.展开更多
文摘Right before the excystment of an Euplotes encysti-cus sawtooth-like folds appeared among the pellicle plas- malemma, the inner and outer alveolar membranes were still sticking together, and were not distinguishable. Mi- crotubular layers already formed at the sites beneath the dorsal cortical pellicle corresponding to vegetative cells,but they still proceed to be organized on the ventral struc-tures. Cristae, highly-tangled with tubular-type struc-tures, appeared on the mitochondria, and were morpho-logically similar to that of vegetative cells. In the cor-tical ciliatures, such as ciliary shafts, kinetosomes, sur-rounding fibrillar cirral baskets, and attached structures of ciliatures, etc., they are different from those in rest- ing cysts which are degenerated or lost. All the cilia- ture microtubules of ciliary shafts are of the 9+2 pattern,but the microtubule-like structure aggregates at triplet - microtubule centers of many kinetosmes, are still under various stages of differentiation. Microtubules beneath the kinetosomal rows are of a developmentally elongated stage; crowded chromatins of various shapes and sizes are found in macronucleus, but there are no nuclear pores (formed by nuclear membrane as in resting cysts) on the nuclear membrane where these chromatins attached.
基金Supported by the National Natural Science Foundation of China (No. 30770238)
文摘We examined the structure and spatial organization of ciliature base-associated microtubules (BAM) in three hypotrichous ciliates (Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi) in fluorescence microscopy. The results revealed that BAM, including the anterior (ALM), posterior longitudinal microtubule (PLM) and the transverse microtubule (TM) bands, are composed of tubulin. The respective microtubular bands have cytoplasmic polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri (MC) in S. rnytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they are directly associated with cell motion.
基金This study was supported by Natural Science Foundation of China (No. 30270160).
文摘The cortical ciliature microtubular organelles of the ciliated protozoan Euplotes Woodruffi were analyzed with FLUTAX and anti-a-tubulin antibody. It showed that the cortical cytoskeleton was composed of non-ciliature structure, ciliature structure including adoral zone of membranelles (AZM), undulating membranes (UM), frontal-ventral-transverse cirri (FVTC), caudal cirri (CC), dorsal kineties, as well as base-associated microtubules. The silverline system is composed of longitudinal and transverse microtubules, concave structure appeared on the cell dorsal side, the base of DK containing rosette-like skeleton structure. All these suggested that the non-ciliature structure, ciliature structure of Euplotes be quite different from that of other species of ciliate, the silverline-system be true pare of cortical microtubute cytoskeleton in Euplotes, rosette structure be part of the basecytoskeleton.
基金Supported by the National Natural Science Foundation of China (No.30770238)
文摘The ultrastructure of extrusomes of the hypotrichous ciliate Pseudourostyla nova was observed in scanning and transmission electron microscopy and enzyme-cytochemistry. The results show that the distribution, morphological characteristics, morphogenesis process, and extrusive process of the extrusomes in P. nova are different from the trichocysts in Paramecium, suggesting that the extrusomes of P. nova can respond to environmental stimuli, play an important role in the defense of this species, and cannot be regarded as "trichocysts". The results also suggest that the extrusomes might be originated from the Golgi apparatus and mature in the cytoplasm; after the extrusion of mature extrusomes, the residual substance might be reabsorbed and reused by the ciliate cell via food vacuoles, and take part in material recycling of the cell.