title: Determination of motility forces on isolated chromosomes with laser tweezers.
abstract: Quantitative determination of the motility forces of chromosomes during cell division is fundamental to understanding a process that is universal among eukaryotic organisms. Using an optical tweezers system, isolated mammalian chromosomes were held in a 1064 nm laser trap. The minimum force required to move a single chromosome was determined to be ≈ 0.8-5 pN. The maximum transverse trapping efficiency of the isolated chromosomes was calculated as ≈ 0.01-0.02. These results confirm theoretical force calculations of ≈ 0.1-12 pN to move a chromosome on the mitotic or meiotic spindle. The verification of these results was carried out by calibration of the optical tweezers when trapping microspheres with a diameter of 4.5-15 µm in media with 1-7 cP viscosity. The results of the chromosome and microsphere trapping experiments agree with optical models developed to simulate trapping of cylindrical and spherical specimens.
authors.affiliation: Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Road, Irvine, CA 92612, USA.
authors.forename: Nima
authors.initials: N
authors.lastname: Khatibzadeh
authors.affiliation: School of Mathematics and Physics, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Alexander B
authors.initials: AB
authors.lastname: Stilgoe
authors.affiliation: School of Mathematics and Physics, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Ann A M
authors.initials: AA
authors.lastname: Bui
authors.affiliation: Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Road, Irvine, CA 92612, USA.
authors.forename: Yesenia
authors.initials: Y
authors.lastname: Rocha
authors.affiliation: Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Road, Irvine, CA 92612, USA.
authors.forename: Gladys M
authors.initials: GM
authors.lastname: Cruz
authors.affiliation: School of Mathematics and Physics, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Vince
authors.initials: V
authors.lastname: Loke
authors.affiliation: Institute of Engineering in Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Linda Z
authors.initials: LZ
authors.lastname: Shi
authors.affiliation: School of Mathematics and Physics, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Timo A
authors.initials: TA
authors.lastname: Nieminen
authors.affiliation: School of Mathematics and Physics, The University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Halina
authors.initials: H
authors.lastname: Rubinsztein-Dunlop
authors.affiliation: 1] Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Road, Irvine, CA 92612, USA [2] Institute of Engineering in Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Berns
mesh_terms: D000465:Algorithms; D000818:Animals; D002455:Cell Division; D002460:Cell Line; D002875:Chromosomes; D055595:Mechanical Phenomena; D008962:Models, Theoretical