Nucleosome mapping.
The basic repeating unit of chromatin, the nucleosome, is known to play a critical role in regulating the process of gene transcription. The positioning of nucleosomes on a promoter is a significant determinant in its responsiveness to gene-inducing signals. For example, positioning and subsequent mobilization of nucleosomes can regulate the access of various DNA factors to underlying DNA templates. Several mechanisms have been proposed to direct the process of nucleosome displacement such as chemical histone modifications, ATP-dependent remodelling, and the incorporation of histone variants. Thus, rather than being an inert molecular structure, chromatin is highly dynamic in response to the transcription process. In this section, we describe two methodologies that allow the determination of exact nucleosome positioning within specific gene regions.
Gévry
Nicolas
N
Département de Biologie, Faculté des Sciences, Université de Sherbrooke, 2500 Boulevard de l-Université, Sherbrooke, QC, Canada, J1K 2R1.
Svotelis
Amy
A
Larochelle
Marc
M
Gaudreau
Luc
L
D000818:Animals; D004247:DNA / Q000302:isolation & purification; D008836:Micrococcal Nuclease / Q000378:metabolism; D008967:Molecular Biology / Q000379:methods*; D009707:Nucleosomes / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000166:cytology
D009707:Nucleosomes; D004247:DNA; D008836:Micrococcal Nuclease