![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
Vol. 12, Issue 9, 2800-2812, September 2001
Department of Biology, CB3280 University of North Carolina, Chapel
Hill, North Carolina 27599-3280
We have used mitotic spindle forces to examine the role of Sir2 and
Ku in chromatin compaction. Escherichia coli lac
operator DNA was placed between two centromeres on a conditional
dicentric chromosome in budding yeast cells and made visible by
expression of a lac repressor-green fluorescent fusion protein.
Centromeres on the same chromatid of a dicentric chromosome attach to
opposite poles ~50% of the time, resulting in chromosome bridges
during anaphase. In cells deleted for yKU70,
yKU80, or SIR2, a 10-kb region of the
dicentric chromosome stretched along the spindle axis to a length of 6 µm during anaphase. On spindle disassembly, stretched chromatin
recoiled to the bud neck and was partitioned to mother and daughter
cells after cytokinesis and cell separation. Chromatin
immunoprecipitation revealed that Sir2 localizes to the lacO region in
response to activation of the dicentric chromosome. These findings
indicate that Ku and Sir proteins are required for proper chromatin
compaction within regions of a chromosome experiencing tension or DNA
damage. The association of Sir2 with the affected region suggests a
direct role in this process, which may include the formation of
heterochromatic DNA.
Online version of this article contains video
material for some figures. Online version is available at
www.molbiolcell.org.
Corresponding author. E-mail
address: kerry_bloom{at}unc.edu.
*
Present address: Department of Cell and Tumor Biology,
City of Hope National Medical Center and Beckman Research Institute, Duarte CA 91010.
This article has been cited by other articles:
|
|
 |
|
  J. K. Fisher, M. Ballenger, E. T. O'Brien, J. Haase, R. Superfine, and K. Bloom DNA relaxation dynamics as a probe for the intracellular environment PNAS, June 9, 2009; 106(23): 9250 - 9255. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S.-i. Hiraga, S. Botsios, and A. D. Donaldson Histone H3 lysine 56 acetylation by Rtt109 is crucial for chromosome positioning J. Cell Biol., November 17, 2008; 183(4): 641 - 651. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. K. Gardner, J. Haase, K. Mythreye, J. N. Molk, M. Anderson, A. P. Joglekar, E. T. O'Toole, M. Winey, E.D. Salmon, D. J. Odde, et al. The microtubule-based motor Kar3 and plus end binding protein Bim1 provide structural support for the anaphase spindle J. Cell Biol., January 10, 2008; 180(1): 91 - 100. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. U. Rafalska-Metcalf and S. M. Janicki Show and tell: visualizing gene expression in living cells J. Cell Sci., July 15, 2007; 120(14): 2301 - 2307. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D. Tytell and P. K. Sorger Analysis of kinesin motor function at budding yeast kinetochores. J. Cell Biol., March 13, 2006; 172(6): 861 - 874. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Bachant, S. R. Jessen, S. E. Kavanaugh, and C. S. Fielding The yeast S phase checkpoint enables replicating chromosomes to bi-orient and restrain spindle extension during S phase distress J. Cell Biol., March 28, 2005; 168(7): 999 - 1012. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. S. Cha and N. Kleckner ATR Homolog Mec1 Promotes Fork Progression, Thus Averting Breaks in Replication Slow Zones Science, July 26, 2002; 297(5581): 602 - 606. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Gasser Visualizing Chromatin Dynamics in Interphase Nuclei Science, May 24, 2002; 296(5572): 1412 - 1416. [Abstract] [Full Text] [PDF]
|
|
