Single Molecule Studies of Chromatin
The DNA in eukaryotic cells is tightly packaged as chromatin through interactions with histone proteins to form nucleosomes. These nucleosomes are themselves packed together through interactions with linker histone and non-histone proteins. In order for processes such as DNA replication, DNA repair, and transcription to occur, the chromatin fiber must be remodeled such that the necessary enzymes can access the DNA. The structure of the chromatin fiber beyond the level of the single nucleosome and the structural changes which accompany the remodeling process are poorly understood. We are studying the structures and forces behind the remodeling process through the use of atomic force microscopy (AFM). This allows both high-resolution imaging of the chromatin, and manipulation of individual fibers. Pulling a single chromatin fiber apart using the AFM tip yields information on the forces which hold the structure together. We have isolated chromatin fibers from chicken erythrocytes and Chinese hamster ovary cell lines. AFM images of these fibers will be presented, along with preliminary data from the manipulation of these fibers using the AFM tip. The implications of these data for the structure of chromatin undergoing the remodeling process are discussed.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 15013718
- Report Number(s):
- UCRL-CONF-202850; TRN: US200803%%1113
- Resource Relation:
- Conference: Presented at: Biophysical Society 48th Annual Meeting, Baltimore, MD, United States, Feb 14 - Feb 18, 2004
- Country of Publication:
- United States
- Language:
- English
Similar Records
Small angle x-ray scattering of chromatin. Radius and mass per unit length depend on linker length
Chd1 remodelers maintain open chromatin and regulate the epigenetics of differentiation