caa a22 4500 445840285 CHVBK 20180317145342.0 cr unu---uuuuu 170323e20110701xx s 000 0 eng 10.1007/s00709-010-0187-8 doi (NATIONALLICENCE)springer-10.1007/s00709-010-0187-8 The ultrastructure of the extrusomes in Pseudourostyla cristata , a hypotrichous ciliated protozoan [Elektronische Daten] [Jun Zhang, Chun Sheng, Lei Tang, Bing Ni, Fukang Gu] By using scanning and transmission electron microscopy, the present study demonstrates a great number of trichocyst-like extrusomes distributed in the cortical cytoplasm of the protozoan Pseudourostyla cristata, a hypotrichous ciliate. Of these, the mature organelles are rod-shaped with a cap consisting of tubular structures, a tip located at the apex of the cap, a body consisting of strateform structures of uneven electron density and an elongated shaft located along the longitudinal central axis of the body. The electron microscopic observations suggest that the extrusive organelles in P. cristata might undergo a morphogenetic process including the following sequential events: the occurrence of the vesicles in the cytoplasm, the condensation of the fibrous substances within the vesicles, the appearance of the electron-dense shaft, and the formation of the cap. In contrast with a large quantity of extrusomes in trophozoit P. cristata, there are no such extrusive organelles in the encysted cells of the ciliate. The phenomena that P. cristata ciliates can readily enter physiological reorganization or encysting phases and discharge a great number of their extrusomes when prepared for SEM and TEM observation suggest that the extrusive process of the extrusomes in P. cristata might have an important influence on the life activity of the ciliate and could be one of the causes leading to the physiological reorganization and the encysting of the ciliate. These reactions of P. cristata might be a protective or defensive response to the environmental changes. Springer-Verlag, 2010 Pseudourostyla cristata nationallicence Extrusomes nationallicence Trichocyst-like extrusive organelles nationallicence Ultrastructure nationallicence Morphology nationallicence Zhang Jun College of Life and Environment Science, Shanghai Normal University, No.100 Gui Lin Lu, 200234, Shanghai, China aut Sheng Chun College of Life and Environment Science, Shanghai Normal University, No.100 Gui Lin Lu, 200234, Shanghai, China aut Tang Lei School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut Ni Bing School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut Gu Fukang School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut Protoplasma Springer Vienna 248/3(2011-07-01), 475-481 0033-183X 248:3<475 2011 248 709 https://doi.org/10.1007/s00709-010-0187-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00709-010-0187-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zhang Jun College of Life and Environment Science, Shanghai Normal University, No.100 Gui Lin Lu, 200234, Shanghai, China aut NATIONALLICENCE 700 1- Sheng Chun College of Life and Environment Science, Shanghai Normal University, No.100 Gui Lin Lu, 200234, Shanghai, China aut NATIONALLICENCE 700 1- Tang Lei School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut NATIONALLICENCE 700 1- Ni Bing School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut NATIONALLICENCE 700 1- Gu Fukang School of Life Sciences, East China Normal University, No.3663 Zhong Shan Bei Lu, 200062, Shanghai, China aut NATIONALLICENCE 773 0- Protoplasma Springer Vienna 248/3(2011-07-01), 475-481 0033-183X 248:3<475 2011 248 709 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer