| Structural highlights
Function
[H2B1J_HUMAN] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling.[1] [2] [3] Has broad antibacterial activity. May contribute to the formation of the functional antimicrobial barrier of the colonic epithelium, and to the bactericidal activity of amniotic fluid.[4] [5] [6]
Publication Abstract from PubMed
The cyclobutane pyrimidine dimer (CPD) is induced in genomic DNA by ultraviolet (UV) light. In mammals, this photolesion is primarily induced within nucleosomal DNA, and repaired exclusively by the nucleotide excision repair (NER) pathway. However, the mechanism by which the CPD is accommodated within the nucleosome has remained unknown. We now report the crystal structure of a nucleosome containing CPDs. In the nucleosome, the CPD induces only limited local backbone distortion, and the affected bases are accommodated within the duplex. Interestingly, one of the affected thymine bases is located within 3.0 A from the undamaged complementary adenine base, suggesting the formation of complementary hydrogen bonds in the nucleosome. We also found that UV-DDB, which binds the CPD at the initial stage of the NER pathway, also efficiently binds to the nucleosomal CPD. These results provide important structural and biochemical information for understanding how the CPD is accommodated and recognized in chromatin.
Crystal structure of the nucleosome containing ultraviolet light-induced cyclobutane pyrimidine dimer.,Horikoshi N, Tachiwana H, Kagawa W, Osakabe A, Matsumoto S, Iwai S, Sugasawa K, Kurumizaka H Biochem Biophys Res Commun. 2016 Feb 26;471(1):117-22. doi:, 10.1016/j.bbrc.2016.01.170. Epub 2016 Feb 2. PMID:26837048[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Kim HS, Cho JH, Park HW, Yoon H, Kim MS, Kim SC. Endotoxin-neutralizing antimicrobial proteins of the human placenta. J Immunol. 2002 Mar 1;168(5):2356-64. PMID:11859126
- ↑ Tollin M, Bergman P, Svenberg T, Jornvall H, Gudmundsson GH, Agerberth B. Antimicrobial peptides in the first line defence of human colon mucosa. Peptides. 2003 Apr;24(4):523-30. PMID:12860195
- ↑ Howell SJ, Wilk D, Yadav SP, Bevins CL. Antimicrobial polypeptides of the human colonic epithelium. Peptides. 2003 Nov;24(11):1763-70. PMID:15019208 doi:10.1016/j.peptides.2003.07.028
- ↑ Kim HS, Cho JH, Park HW, Yoon H, Kim MS, Kim SC. Endotoxin-neutralizing antimicrobial proteins of the human placenta. J Immunol. 2002 Mar 1;168(5):2356-64. PMID:11859126
- ↑ Tollin M, Bergman P, Svenberg T, Jornvall H, Gudmundsson GH, Agerberth B. Antimicrobial peptides in the first line defence of human colon mucosa. Peptides. 2003 Apr;24(4):523-30. PMID:12860195
- ↑ Howell SJ, Wilk D, Yadav SP, Bevins CL. Antimicrobial polypeptides of the human colonic epithelium. Peptides. 2003 Nov;24(11):1763-70. PMID:15019208 doi:10.1016/j.peptides.2003.07.028
- ↑ Horikoshi N, Tachiwana H, Kagawa W, Osakabe A, Matsumoto S, Iwai S, Sugasawa K, Kurumizaka H. Crystal structure of the nucleosome containing ultraviolet light-induced cyclobutane pyrimidine dimer. Biochem Biophys Res Commun. 2016 Feb 26;471(1):117-22. doi:, 10.1016/j.bbrc.2016.01.170. Epub 2016 Feb 2. PMID:26837048 doi:http://dx.doi.org/10.1016/j.bbrc.2016.01.170
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