Ref ID : 4865
Igor B. Raikov and Valentina G. Kovaleva; Comparative Ultrastructure of the Cytoplasm in Species of the Genus Tracheloraphis (Ciliophora: Karyorelictida) II. Endoplasmic Organelles and Genesis of Rhabdocysts. Arch.Protistenk 146:1-11, 1995
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The endoplasm of five Tracheloraphis species, Tr. dogieli, Tr. phoenicopterus, Tr. totevi, Tr. crassus and Tr. caudatus, has been investigated. The endoplasm of all species is permeated with an extensive general lacunary system, the ground cytoplasm being reduced to a network of interconnected cytoplasmic islets which contain the cell organelles. The mitochondria have tubular cristae and variably dense matrix. They accumulate beneath the myonemes and under the non-ciliated stripe. Some mitochondria of Tr. dogieli show reduced cristae. The Golgi bodies are numerous near the ciliated body surface and consist of up to ten flattened cisternae. Some species (Tr. phoenicopterus, Tr. crassus) contain refractile electron-lucent inclusions lying inside the endoplasmic lacunae, others (Tr. dogieli) contain large protein globules, devoid of own membrane, lying in the ground cytoplasm. The lipid droplets also lie in the ground cytoplasm and are not surrounded with an own membrane. The rhabdocysts are formed within membrane vesicles inside endoplasmic islets which are rich in ribosomes. In the vesicles, the head and the shaft of the extrusomes are progressively formed. At last, rhabdocysts migrate to the periphery of the cell and become docked in the interkinetal papillae accompanying ventral kineties.