Title :
Reversible and irreversible unfolding of eukaryote chromosomes by force
Author :
Marko, John F. ; Poirier, M. ; Eroglu, Sertac ; Chatenay, Didier
Author_Institution :
Dept. of Phys., Illinois Univ., Chicago, IL, USA
Abstract :
We have carried out studies of metaphase chromosomes in primary explant cultures of newt lung epithelia, using in situ microsurgery and force measurement. The chromosomes are elastic over a five-fold range of extension, with a force constant of about one nanonewton (nN). For larger extensions, chromosomes are permanently elongated; if stretched beyond 30 times, their cross-sectional diameter is increased after relaxation. Fluorescence studies indicate that histone proteins are not being removed. We conclude that we are first unfolding and then breaking chromosome-folding proteins by extension
Keywords :
DNA; biological techniques; biomechanics; cellular biophysics; elasticity; fluorescence; force measurement; lung; proteins; breaking by extension; cell division; chromosome-folding proteins; elasticity; eukaryote chromosomes; fluorescence; force hysteresis; force measurement; histone antibodies; in situ microsurgery; irreversible unfolding; metaphase chromosomes; micromanipulation; newt lung epithelia; permanently elongated; primary explant cultures; reversible unfolding; unfolding by force; Biological cells; Biomedical engineering; Cells (biology); DNA; Elasticity; Electromigration; Frequency; Instruments; Low-frequency noise; Lungs; Microsurgery; Noise measurement; Performance analysis; Proteins; Signal analysis; Stress; Surgery; Temperature sensors; Testing;
Conference_Titel :
[Engineering in Medicine and Biology, 1999. 21st Annual Conference and the 1999 Annual Fall Meetring of the Biomedical Engineering Society] BMES/EMBS Conference, 1999. Proceedings of the First Joint
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-5674-8
DOI :
10.1109/IEMBS.1999.802114
