Histone H3
| H3 histone, family 3A (H3.3A) | |||||||
|---|---|---|---|---|---|---|---|
| Identifiers | |||||||
| Symbol | H3F3A | ||||||
| Alt. symbols | H3F3 | ||||||
| NCBI gene | 3020 | ||||||
| HGNC | 4764 | ||||||
| OMIM | 601128 | ||||||
| RefSeq | NM_002107 | ||||||
| UniProt | Q66I33 | ||||||
| Other data | |||||||
| Locus | Chr. 1q41 | ||||||
| |||||||
| H3 histone, family 3B (H3.3B) | |||||||
|---|---|---|---|---|---|---|---|
| Identifiers | |||||||
| Symbol | H3F3B | ||||||
| NCBI gene | 3021 | ||||||
| HGNC | 4765 | ||||||
| OMIM | 601058 | ||||||
| RefSeq | NM_005324 | ||||||
| UniProt | P84243 | ||||||
| Other data | |||||||
| Locus | Chr. 17q25 | ||||||
| |||||||
Histone H3is one of the five mainhistonesinvolved in the structure ofchromatinineukaryotic cells.[1][2]Featuring a main globular domain and a longN-terminal tail,H3 is involved with the structure of thenucleosomesof the 'beads on a string' structure. Histone proteins are highlypost-translationally modifiedhowever Histone H3 is the most extensively modified of the five histones. The term "Histone H3" alone is purposely ambiguous in that it does not distinguish between sequence variants or modification state. Histone H3 is an important protein in the emerging field ofepigenetics,where its sequence variants and variable modification states are thought to play a role in the dynamic and long term regulation of genes.
Epigenetics and post-translational modifications[edit]
TheN-terminusof H3 protrudes from the globularnucleosomecore and is susceptible to post-translational modification that influence cellular processes. These modifications include the covalent attachment of methyl or acetyl groups tolysineandarginineamino acids and the phosphorylation ofserineorthreonine.Di- and Tri-methylation of lysine 9 are associated with repression andheterochromatin(seeH3K9me2andH3K9me3), while mono-methylation of K4 (K4 corresponds to lysine residue at 4th position)(seeH3K4me1), is associated with active genes.[3][4]Acetylation of histone H3 at several lysine positions in the histone tail is performed byhistone acetyltransferaseenzymes (HATs). Acetylation of lysine14 is commonly seen in genes that are being actively transcribed intoRNA(seeH3K14ac).
Sequence variants[edit]
Mammalian cells have seven known sequence variants of histone H3. These are denoted as Histone H3.1, Histone H3.2, Histone H3.3, Histone H3.4 (H3T), Histone H3.5, Histone H3.X and Histone H3.Y but have highly conserved sequences differing only by a few amino acids.[5][6]Histone H3.3 has been found to play an important role in maintaining genome integrity during mammalian development.[7]Histone variants from different organisms, their classification and variant specific features can be found in"HistoneDB - with Variants"database.
Genetics[edit]
Histone H3s are coded by several genes in the human genome, including:
- H3.1:HIST1H3A,HIST1H3B,HIST1H3C,HIST1H3D,HIST1H3E,HIST1H3F,HIST1H3G,HIST1H3H,HIST1H3I,HIST1H3J
- H3.2:HIST2H3A,HIST2H3C,HIST2H3D
- H3.3:H3F3A,H3F3B
See also[edit]
References[edit]
- ^Bhasin M, Reinherz EL, Reche PA (2006)."Recognition and classification of histones using support vector machine"(PDF).Journal of Computational Biology.13(1): 102–12.doi:10.1089/cmb.2006.13.102.PMID16472024.
- ^Hartl DL, Freifelder D, Snyder LA (1988).Basic Genetics.Boston: Jones and Bartlett Publishers.ISBN978-0-86720-090-4.
- ^Rosenfeld JA, Wang Z, Schones DE, Zhao K, DeSalle R, Zhang MQ (March 2009)."Determination of enriched histone modifications in non-genic portions of the human genome".BMC Genomics.10:143.doi:10.1186/1471-2164-10-143.PMC2667539.PMID19335899.
- ^Lachner M, O'Carroll D, Rea S, Mechtler K, Jenuwein T (Mar 2001)."Methylation of histone H3 lysine 9 creates a binding site for HP1 proteins".Nature.410(6824): 116–20.Bibcode:2001Natur.410..116L.doi:10.1038/35065132.PMID11242053.S2CID4331863.
- ^Marzluff WF, Gongidi P, Woods KR, Jin J, Maltais LJ (Nov 2002)."The human and mouse replication-dependent histone genes".Genomics.80(5): 487–98.doi:10.1016/S0888-7543(02)96850-3.PMID12408966.
- ^Hake SB, Garcia BA, Duncan EM, Kauer M, Dellaire G, Shabanowitz J, Bazett-Jones DP, Allis CD, Hunt DF (Jan 2006)."Expression patterns and post-translational modifications associated with mammalian histone H3 variants".The Journal of Biological Chemistry.281(1): 559–68.doi:10.1074/jbc.M509266200.PMID16267050.
- ^Jang CW, Shibata Y, Starmer J, Yee D, Magnuson T (Jul 2015)."Histone H3.3 maintains genome integrity during mammalian development".Genes & Development.29(13): 1377–92.doi:10.1101/gad.264150.115.PMC4511213.PMID26159997.