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<table><tr><td colspan='2'>[[6l4a]] is a 26 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6L4A OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6L4A FirstGlance]. <br>
<table><tr><td colspan='2'>[[6l4a]] is a 26 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6L4A OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6L4A FirstGlance]. <br>
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[[Category: Human]]
[[Category: Human]]
[[Category: Large Structures]]
[[Category: Large Structures]]
Revision as of 22:29, 6 March 2020
H3-H3-H3 tri-nucleosome with the 22 base-pair linker DNA
6l4a is a 26 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[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 histone H3 variant CENP-A is a crucial epigenetic marker for centromere specification. CENP-A forms a characteristic nucleosome and dictates the higher-order configuration of centromeric chromatin. However, little is known about how the CENP-A nucleosome affects the architecture of centromeric chromatin. In this study, we reconstituted tri-nucleosomes mimicking a centromeric nucleosome arrangement containing the CENP-A nucleosome, and determined their 3D structures by cryoelectron microscopy. The H3-CENP-A-H3 tri-nucleosomes adopt an untwisted architecture, with an outward-facing linker DNA path between nucleosomes. This is distinct from the H3-H3-H3 tri-nucleosome architecture, with an inward-facing DNA path. Intriguingly, the untwisted architecture may allow the CENP-A nucleosome to be exposed to the solvent in the condensed chromatin model. These results provide a structural basis for understanding the 3D configuration of CENP-A-containing chromatin, and may explain how centromeric proteins can specifically target the CENP-A nucleosomes buried in robust amounts of H3 nucleosomes in centromeres.
Cryo-EM Structures of Centromeric Tri-nucleosomes Containing a Central CENP-A Nucleosome.,Takizawa Y, Ho CH, Tachiwana H, Matsunami H, Kobayashi W, Suzuki M, Arimura Y, Hori T, Fukagawa T, Ohi MD, Wolf M, Kurumizaka H Structure. 2019 Nov 7. pii: S0969-2126(19)30357-0. doi:, 10.1016/j.str.2019.10.016. PMID:31711756[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
↑ Takizawa Y, Ho CH, Tachiwana H, Matsunami H, Kobayashi W, Suzuki M, Arimura Y, Hori T, Fukagawa T, Ohi MD, Wolf M, Kurumizaka H. Cryo-EM Structures of Centromeric Tri-nucleosomes Containing a Central CENP-A Nucleosome. Structure. 2019 Nov 7. pii: S0969-2126(19)30357-0. doi:, 10.1016/j.str.2019.10.016. PMID:31711756 doi:http://dx.doi.org/10.1016/j.str.2019.10.016
