Abstract
The macronucleus in Tokophrya infusionum is composed of numerous Feulgen-positive chromatin bodies (about 0.5 µ in diameter) which appear in thin sections as a dense spongework, homogeneous throughout. The same appearance characterizes metaphase chromosomes of higher forms. Some chromatin bodies of the macronucleus were found to possess a highly organized structure in certain old organisms. This structure appears in cross-sections as a honeycomb and in longitudinal sections as parallel lines about 120 A in diameter evenly spaced (about 230 A). As far as is known this is the first time a regular structure has been found in bodies of chromosomal character at the dimensional level presently explored by electron microscopy. The demonstration that OsO4 can preserve order in chromatin material is another significant aspect of these findings.
Full Text
The Full Text of this article is available as a PDF (1.1 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- AFZELIUS B. A. The ultrastructure of the nuclear membrane of the sea urchin oocyte as studied with the electron microscope. Exp Cell Res. 1955 Feb;8(1):147–158. doi: 10.1016/0014-4827(55)90051-3. [DOI] [PubMed] [Google Scholar]
- Kimball R. F. The Structure of the Macronucleus of Paramecium Aurelia. Proc Natl Acad Sci U S A. 1953 Apr;39(4):345–347. doi: 10.1073/pnas.39.4.345. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LILLY D. M. The nutrition of carnivorous protozoa. Ann N Y Acad Sci. 1953 Oct 14;56(5):910–920. doi: 10.1111/j.1749-6632.1953.tb30269.x. [DOI] [PubMed] [Google Scholar]
- MOSES M. J. Nucleoproteins and the cytological chemistry of Paramecium nuclei. Proc Soc Exp Biol Med. 1949 Aug;71(4):537–539. doi: 10.3181/00379727-71-17247. [DOI] [PubMed] [Google Scholar]
- PORTER K. R., BLUM J. A study in microtomy for electron microscopy. Anat Rec. 1953 Dec;117(4):685–710. doi: 10.1002/ar.1091170403. [DOI] [PubMed] [Google Scholar]
- RUDZINSKA M. A. Giant individuals and vigor of populations in Tokophyra infusionum. Ann N Y Acad Sci. 1953 Oct 14;56(5):1087–1090. doi: 10.1111/j.1749-6632.1953.tb30292.x. [DOI] [PubMed] [Google Scholar]
- RUDZINSKA M. A. Overfeeding and life span in Tokophrya infusionum. J Gerontol. 1952 Oct;7(4):544–548. doi: 10.1093/geronj/7.4.544. [DOI] [PubMed] [Google Scholar]
- RUDZINSKA M. A., PORTER K. R. Electron microscope study of intact tentacles and disc in Tokophrya infusionum. Experientia. 1954 Nov 15;10(11):460–462. doi: 10.1007/BF02170400. [DOI] [PubMed] [Google Scholar]
- WATSON M. L. The nuclear envelope; its structure and relation to cytoplasmic membranes. J Biophys Biochem Cytol. 1955 May 25;1(3):257–270. doi: 10.1083/jcb.1.3.257. [DOI] [PMC free article] [PubMed] [Google Scholar]