Program

Poster Presentations

Day 2, May 16（Wed.）　　Poster

2P-36　　PDF

Structural diversity of nucleosome by ion mobility mass spectrometry

(¹Hiroshima Univ., ²Yokohama City Univ.)
^oKazumi Saikusa^1,2, Sotaro Fuchigami², Satoko Akashi²

Nucleosome is the basic unit of chromatin, which is composed of a histone octamer wrapped by ∼146 bp of DNA. The structural characterization of nucleosome is significant for understanding the mechanism of nucleosome assembly and disassembly by various epigenetic factors such as histone modification. In this study, we investigated gas-phase structure of nucleosome using ion mobility mass spectrometry and molecular dynamics simulation. Experimentally observed arrival times of nucleosome ions showed a wide distribution, implying three populations in the native-like state. To examine their structures, computational simulations of nucleosome were performed first in solution and then in a solvent-free environment to mimic the rapid hydration, or in completely solvent-free environment to obtain equilibrated structure in vacuo. We will discuss the structures of nucleosome in gas phase by comparing the experimental and theoretical collision cross-section distributions.