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Structure Change from ?-Strand and Turn to ?-Helix in Histone H2A-H2B Induced by DNA Damage Response.

ABSTRACT: Using synchrotron radiation-based circular dichroism spectroscopy, we found that the DNA damage response induces an increase of ?-helix structure and a decrease of ?-strand and turn structures in histone H2A-H2B extracted from x-irradiated human HeLa cells. The structural alterations correspond to the assumption that an average of eight amino acid residues form new ?-helix structures at 310 K. We propose the structural transition from ?-strand and turn structures to an ?-helix structure in H2A-H2B as a novel, to our knowledge, process involved in the DNA damage response.

SUBMITTER: Izumi Y

PROVIDER: S-EPMC4945303 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Structure Change from β-Strand and Turn to α-Helix in Histone H2A-H2B Induced by DNA Damage Response.

Izumi Yudai Y Fujii Kentaro K Wien Frank F Houée-Lévin Chantal C Lacombe Sandrine S Salado-Leza Daniela D Porcel Erika E Masoud Rawand R Yamamoto Satoshi S Réfrégiers Matthieu M Hervé du Penhoat Marie-Anne MA Yokoya Akinari A

Biophysical journal 20160701 1

Using synchrotron radiation-based circular dichroism spectroscopy, we found that the DNA damage response induces an increase of α-helix structure and a decrease of β-strand and turn structures in histone H2A-H2B extracted from x-irradiated human HeLa cells. The structural alterations correspond to the assumption that an average of eight amino acid residues form new α-helix structures at 310 K. We propose the structural transition from β-strand and turn structures to an α-helix structure in H2A-H ...[more]

PMID: 27410735

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