Abstract

We have analyzed human centromeric chromatin containing CENPA from HeLa cells in culture using Chromatin IP followed by atomic force microscopy measurements and mass spectrophotometry. Thus far, we have identified that the CENPA chromatin structure is uniquely organized during interphase, and has fundamentally different characteristics from the rest of the chromatin which packages the genome. WE have computationally modeled CENP-A/H4 in the nucleosome and the dimer state, and demonstrated the flexiblity arises from the core of the nucleosome, causing the DNA to be very accessible. WE have performed magnetic tweezer experiments with collaborators, showing that CENP-A nucleosomes cannot withstand substantial more force than canonical nucleosomes, regardless of DNA sequence, suggesting other epigenetic features are required for centromere stability.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Investigator-Initiated Intramural Research Projects (ZIA)
Project #
1ZIABC011207-10
Application #
9779831
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
10
Fiscal Year
2018
Total Cost
Indirect Cost

  Institution

Name
Basic Sciences
Department
Type
DUNS #
City
State
Country
Zip Code

  Publications

Nuccio, A G; Bui, M; Dalal, Y et al. (2017) Mass Spectrometry-Based Methodology for Identification of Native Histone Variant Modifications From Mammalian Tissues and Solid Tumors. Methods Enzymol 586:275-290
Vlijm, R; Kim, S H; De Zwart, P L et al. (2017) The supercoiling state of DNA determines the handedness of both H3 and CENP-A nucleosomes. Nanoscale 9:1862-1870
Bui, Minh; Pitman, Mary; Nuccio, Arthur et al. (2017) Internal modifications in the CENP-A nucleosome modulate centromeric dynamics. Epigenetics Chromatin 10:17
Zhao, Haiqing; Winogradoff, David; Bui, Minh et al. (2016) Promiscuous Histone Mis-Assembly Is Actively Prevented by Chaperones. J Am Chem Soc 138:13207-13218
Kim, Sung Hyun; Vlijm, Rifka; van der Torre, Jaco et al. (2016) CENP-A and H3 Nucleosomes Display a Similar Stability to Force-Mediated Disassembly. PLoS One 11:e0165078
Quénet, D; Sturgill, D; Dalal, Y (2016) Identifying Centromeric RNAs Involved in Histone Dynamics In Vivo. Methods Enzymol 573:445-66
Winogradoff, David; Zhao, Haiqing; Dalal, Yamini et al. (2015) Shearing of the CENP-A dimerization interface mediates plasticity in the octameric centromeric nucleosome. Sci Rep 5:17038
Quénet, Delphine; Dalal, Yamini (2015) Correction: a long non-coding RNA is required for targeting centromeric protein A to the human centromere. Elife 4:
Dalal, Yamini; McNally, James G (2014) Now you see it, now you don't: a biochemist's primer for advances in high-resolution microscopy: comment on ""Biomolecular dynamics and binding studies in the living cell"" by Stephan Diekmann and Christian Hoischen. Phys Life Rev 11:36-7; discussion 38
Walkiewicz, Marcin P; Bui, Minh; Quénet, Delphine et al. (2014) Tracking histone variant nucleosomes across the human cell cycle using biophysical, biochemical, and cytological analyses. Methods Mol Biol 1170:589-615

Showing the most recent 10 out of 19 publications