ISSN:
1432-0878
Keywords:
Endoplasmic reticulum
;
Membrane differentiation
;
Tetrahymena pyriformis
;
Ciliate ultrastructure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Two special kinds of smooth surfaced differentiations of the endoplasmic reticulum (ER) of the ciliate Tetrahymena pyriformis are described. (A) A novel type of cytomembrane structure is represented by localized bifacial regions in which one side of the cisterna is studded with ribosomes, flexible in outline and of a cytomembraneous ultrastructure and the other side has a smooth, straight profile and a plasma membrane-like triple-layered appearance. Such smooth patches of predominantly rough ER-cisternae have a tendency to pair with a separation of ca. 250 Å. The micrographs suggest a participation of such patches in the formation of vesicles and/or dictyosomes. (B) Tubular structures, including those with microtubular as well as with “macrotubular” (300–650 Å) diameters, can be in continuity with ER profiles. Possible origins and functions of these tubular forms are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00337632
Permalink
