title: Role of Extrachromosomal Histone H2B on Recognition of DNA Viruses and Cell Damage.
abstract: Histones are essential components of chromatin structure, and histone modification plays an important role in various cellular functions including transcription, gene silencing, and immunity. Histones also play distinct roles in extrachromosomal settings. Extrachromosomal histone H2B acts as a cytosolic sensor to detect double-stranded DNA (dsDNA) fragments derived from infectious agents or damaged cells to activate innate and acquired immune responses in various cell types. It also physically interacts with interferon (IFN)-β promoter stimulator 1 (IPS-1), an essential adaptor molecule that activates innate immunity, through COOH-terminal importin 9-related adaptor organizing histone H2B and IPS-1 (CIAO), resulting in a distinct signaling complex that induces dsDNA-induced type I IFN production. Such a molecular platform acts as a cellular sensor to recognize aberrant dsDNA in cases of viral infection and cell damage. This mechanism may also play roles in autoimmunity, transplantation rejection, gene-mediated vaccines, and other therapeutic applications.
authors.affiliation: Laboratory of Adjuvant Innovation, National Institute of Biomedical Innovation Ibaraki, Osaka, Japan ; Laboratory of Vaccine Science, Immunology Frontier Research Center, World Premier International Research Center, Osaka University Suita, Osaka, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Kobiyama
authors.forename: Akira
authors.initials: A
authors.lastname: Kawashima
authors.forename: Nao
authors.initials: N
authors.lastname: Jounai
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Takeshita
authors.forename: Ken J
authors.initials: KJ
authors.lastname: Ishii
authors.forename: Tetsuhide
authors.initials: T
authors.lastname: Ito
authors.forename: Koichi
authors.initials: K
authors.lastname: Suzuki
keywords: DNA damage; DNA sensor; epigenetic modifications; extrachromosomal histone; virus infection