Abstract
Human lymphocytes were grown in short-term tissue culture and were arrested in metaphase with Colcemid. Their chromosomes were prepared by the Langmuir trough-critical point drying technique and were examined under the electron microscope. In addition, some chromosomes were digested with trypsin, Pronase, or DNase. The chromosomes consist entirely of tightly packed, 240 ± 50-A chromatin fibers. Trypsin and Pronase treatments induce relaxation of fiber packing and reveal certain underlying fiber arrangements. Furthermore, trypsin treatment demonstrates that the chromatin fiber has a 25–50 A trypsin-resistant core surrounded by a trypsin-sensitive sheath. DNase digestion suggests that this core contains DNA.
Full Text
The Full Text of this article is available as a PDF (1.8 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BAJER A. Ciné-micrographic studies on mitosis in endosperm. IV. The mitotic contraction stage. Exp Cell Res. 1958 Apr;14(2):245–256. doi: 10.1016/0014-4827(58)90183-6. [DOI] [PubMed] [Google Scholar]
- BARNICOT N. A., HUXLEY H. E. The electron microscopy of unsectioned human chromosomes. Ann Hum Genet. 1961 Dec;25:253–258. doi: 10.1111/j.1469-1809.1962.tb01525.x. [DOI] [PubMed] [Google Scholar]
- Barnicot N. A. A study of newt mitotic chromosomes by negative staining. J Cell Biol. 1967 Mar;32(3):585–603. doi: 10.1083/jcb.32.3.585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barnicot N. A., Huxley H. E. Electron microscope observations on mitotic chromosomes. Q J Microsc Sci. 1965 Sep;106(3):197–214. [PubMed] [Google Scholar]
- Bastia D., Swaminathan M. S. Ultrastructure of interphase chromosomes. Exp Cell Res. 1967 Oct;48(1):18–26. doi: 10.1016/0014-4827(67)90272-8. [DOI] [PubMed] [Google Scholar]
- Bridges C. B. THE BAR "GENE" A DUPLICATION. Science. 1936 Feb 28;83(2148):210–211. doi: 10.1126/science.83.2148.210. [DOI] [PubMed] [Google Scholar]
- Brinkley B. R., Stubblefield E. The fine structure of the kinetochore of a mammalian cell in vitro. Chromosoma. 1966;19(1):28–43. doi: 10.1007/BF00332792. [DOI] [PubMed] [Google Scholar]
- Creighton H. B., McClintock B. A Correlation of Cytological and Genetical Crossing-Over in Zea Mays. Proc Natl Acad Sci U S A. 1931 Aug;17(8):492–497. doi: 10.1073/pnas.17.8.492. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DALES S. A study of the fine structure of mammalian somatic chromosomes. Exp Cell Res. 1960 Apr;19:577–590. doi: 10.1016/0014-4827(60)90065-3. [DOI] [PubMed] [Google Scholar]
- DuPraw E. J. Evidence for a 'folded-fibre' organization in human chromosomes. Nature. 1966 Feb 5;209(5023):577–581. doi: 10.1038/209577a0. [DOI] [PubMed] [Google Scholar]
- DuPraw E. J. Macromolecular organization of nuclei and chromosomes: a folded fibre model based on whole-mount electron microscopy. Nature. 1965 Apr 24;206(982):338–343. doi: 10.1038/206338a0. [DOI] [PubMed] [Google Scholar]
- DuPraw E. J., Rae P. M. Polytene chromosome structure in relation to the "folded fibre" concept. Nature. 1966 Nov 5;212(5062):598–600. doi: 10.1038/212598a0. [DOI] [PubMed] [Google Scholar]
- Dupraw E. J. THE ORGANIZATION OF NUCLEI AND CHROMOSOMES IN HONEYBEE EMBRYONIC CELLS. Proc Natl Acad Sci U S A. 1965 Jan;53(1):161–168. doi: 10.1073/pnas.53.1.161. [DOI] [PMC free article] [PubMed] [Google Scholar]
- EVANS H. J. UPTAKE OF 3H-THYMIDINE AND PATTERNS OF DNA REPLICATION IN NUCLEI AND CHROMOSOMES OF VICIA FABA. Exp Cell Res. 1964 Jul;35:381–393. doi: 10.1016/0014-4827(64)90104-1. [DOI] [PubMed] [Google Scholar]
- GALL J. G. On the submicroscopic structure of chromosomes. Brookhaven Symp Biol. 1956 Feb;(8):17–32. [PubMed] [Google Scholar]
- GALL J. Chromosome fibers from an interphase nucleus. Science. 1963 Jan 11;139(3550):120–121. doi: 10.1126/science.139.3550.120. [DOI] [PubMed] [Google Scholar]
- Gavosto F., Regoraro L., Rovera G., Masera P. Time sequence of DNA replication in heteropycnotic X. Nature. 1967 Jul 29;215(5100):535–536. doi: 10.1038/215535b0. [DOI] [PubMed] [Google Scholar]
- Giménez-Martin G., López-Sáez J. F., Marcos-Moreno A. Structure of the centromere in telocentric chromosomes. Experientia. 1965 Jul 15;21(7):391–392. doi: 10.1007/BF02139759. [DOI] [PubMed] [Google Scholar]
- Govaerts A., Dekegel D. Electron micrography of human chromosomes. Nature. 1966 Feb 19;209(5025):831–832. doi: 10.1038/209831a0. [DOI] [PubMed] [Google Scholar]
- HOTTA Y., BASSEL A. MOLECULAR SIZE AND CIRCULARITY OF DNA IN CELLS OF MAMMALS AND HIGHER PLANTS. Proc Natl Acad Sci U S A. 1965 Feb;53:356–362. doi: 10.1073/pnas.53.2.356. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hsu T. C., Brinkley B. R., Arrighi F. E. The structure and behavior of the nucleolus organizer in mammalian cells. Chromosoma. 1967;23(2):137–153. doi: 10.1007/BF00331109. [DOI] [PubMed] [Google Scholar]
- Jokelainen P. T. The ultrastructure and spatial organization of the metaphase kinetochore in mitotic rat cells. J Ultrastruct Res. 1967 Jul;19(1):19–44. doi: 10.1016/s0022-5320(67)80058-3. [DOI] [PubMed] [Google Scholar]
- KAUFMANN B. P., MCDONALD M. R. Organization of the chromosome. Cold Spring Harb Symp Quant Biol. 1956;21:233–246. doi: 10.1101/sqb.1956.021.01.019. [DOI] [PubMed] [Google Scholar]
- Luykx P. The structure of the kinetochore in meiosis and mitosis in Urechis eggs. Exp Cell Res. 1965 Sep;39(2):643–657. doi: 10.1016/0014-4827(65)90068-6. [DOI] [PubMed] [Google Scholar]
- MOLE-BAJER J. Cine-micrographic analysis of C-mitosis in endosperm. Chromosoma. 1958;9(4):332–358. doi: 10.1007/BF02568085. [DOI] [PubMed] [Google Scholar]
- MOORHEAD P. S., NOWELL P. C., MELLMAN W. J., BATTIPS D. M., HUNGERFORD D. A. Chromosome preparations of leukocytes cultured from human peripheral blood. Exp Cell Res. 1960 Sep;20:613–616. doi: 10.1016/0014-4827(60)90138-5. [DOI] [PubMed] [Google Scholar]
- MORISHIMA A., GRUMBACH M. M., TAYLOR J. H. Asynchronous duplication of human chromosomes and the origin of sex chromatin. Proc Natl Acad Sci U S A. 1962 May 15;48:756–763. doi: 10.1073/pnas.48.5.756. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McCLINTOCK B. Chromosome organization and genic expression. Cold Spring Harb Symp Quant Biol. 1951;16:13–47. doi: 10.1101/sqb.1951.016.01.004. [DOI] [PubMed] [Google Scholar]
- Miller O. L., Jr Fine structure of lampbrush chromosomes. Natl Cancer Inst Monogr. 1965 Dec;18:79–99. [PubMed] [Google Scholar]
- NEBEL B. R., COULON E. M. Enzyme effects on pachytene chromosomes of the male pigeon evaluated with the electron microscope. Chromosoma. 1962;13:292–299. doi: 10.1007/BF00577044. [DOI] [PubMed] [Google Scholar]
- Nance W. E., Engel E. Autosomal deletion mapping in man. Science. 1967 Feb 10;155(3763):692–694. doi: 10.1126/science.155.3763.692. [DOI] [PubMed] [Google Scholar]
- OSGOOD E. E., JENKINS D. P., BROOKS R., LAWSON R. K. ELECTRON MICROGRAPHIC STUDIES OF THE EXPANDED AND UNCOILED CHROMOSOMES FROM HUMAN LEUKOCYTES. Ann N Y Acad Sci. 1964 Feb 28;113:717–726. doi: 10.1111/j.1749-6632.1964.tb40699.x. [DOI] [PubMed] [Google Scholar]
- Ohnuki Y. Demonstration of the spiral structure of human chromosomes. Nature. 1965 Nov 27;208(5013):916–917. doi: 10.1038/208916a0. [DOI] [PubMed] [Google Scholar]
- Painter T. S. A NEW METHOD FOR THE STUDY OF CHROMOSOME REARRANGEMENTS AND THE PLOTTING OF CHROMOSOME MAPS. Science. 1933 Dec 22;78(2034):585–586. doi: 10.1126/science.78.2034.585. [DOI] [PubMed] [Google Scholar]
- Peacock W. J. Chromosome replication. Natl Cancer Inst Monogr. 1965 Dec;18:101–131. [PubMed] [Google Scholar]
- Pelling C. A replicative and synthetic chromosomal unit--the modern concept of the chromomere. Proc R Soc Lond B Biol Sci. 1966 Mar 22;164(995):279–289. doi: 10.1098/rspb.1966.0030. [DOI] [PubMed] [Google Scholar]
- RIS H. Ultrastructure and molecular organization of genetic systems. Can J Genet Cytol. 1961 Jun;3:95–120. doi: 10.1139/g61-015. [DOI] [PubMed] [Google Scholar]
- Rae P. M. Whole mount electron microscopy of Drosophila salivary chromosomes. Nature. 1966 Oct 8;212(5058):139–142. doi: 10.1038/212139a0. [DOI] [PubMed] [Google Scholar]
- Ris H. Fine structure of chromosomes. Proc R Soc Lond B Biol Sci. 1966 Mar 22;164(995):246–257. doi: 10.1098/rspb.1966.0027. [DOI] [PubMed] [Google Scholar]
- SASAKI M. S., MAKINO S. The demonstration of secondary constrictions in human chromosomes by means of a new technique. Am J Hum Genet. 1963 Mar;15:24–33. [PMC free article] [PubMed] [Google Scholar]
- SCHMID W. DNA REPLICATION PATTERNS OF HUMAN CHROMOSOMES. Cytogenetics. 1963;2:175–193. doi: 10.1159/000129778. [DOI] [PubMed] [Google Scholar]
- SOLARI A. J. STRUCTURE OF THE CHROMATIN IN SEA URCHIN SPERM. Proc Natl Acad Sci U S A. 1965 Mar;53:503–511. doi: 10.1073/pnas.53.3.503. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwarzacher H. G., Schnedl W. Elektronenmikroskopische Untersuchungen menschlicher Metaphasen-Chromosomen. Humangenetik. 1967;4(2):153–165. doi: 10.1007/BF00291260. [DOI] [PubMed] [Google Scholar]
- Trosko J. E., Wolff S. Strandedness of Vicia faba chromosomes as revealed by enzyme digestion studies. J Cell Biol. 1965 Jul;26(1):125–135. doi: 10.1083/jcb.26.1.125. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WOLFE S. L. THE FINE STRUCTURE OF ISOLATED CHROMOSOMES. J Ultrastruct Res. 1965 Feb;12:104–112. doi: 10.1016/s0022-5320(65)80010-7. [DOI] [PubMed] [Google Scholar]
- Wolfe S. L., Grim J. N. The relationship of isolated chromosome fibers to the fibers of the embedded nucleus. J Ultrastruct Res. 1967 Aug;19(3):382–397. doi: 10.1016/s0022-5320(67)80226-0. [DOI] [PubMed] [Google Scholar]
- Wolfe S. L., John B. The organization and ultrastructure of male meiotic chromosomes n Oncopeltus fasciatus. Chromosoma. 1965;17(2):85–103. doi: 10.1007/BF00330076. [DOI] [PubMed] [Google Scholar]
- Zakharov A. F., Egolina N. A. Asynchrony of DNA replication and mitotic spiralization along heterochromatic portions of Chinese hamster chromosomes. Chromosoma. 1968;23(4):365–385. doi: 10.1007/BF00625285. [DOI] [PubMed] [Google Scholar]
