Histone H3

Enables cupric reductase activity. Involved in several processes, including cellular copper ion homeostasis; nucleic acid metabolic process; and sexual sporulation resulting in formation of a cellular spore. Located in nucleus. Part of CENP-A containing nucleosome and replication fork protection complex.

Histone H3 is one of the five main histone proteins involved in the structure of chromatin in eukaryotic cells. Featuring a main globular domain and a long N-terminal tail, H3 is involved with the structure of the nucleosomes of the 'beads on a string' structure. Histone proteins are highly post-translationally modified however 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 of epigenetics, where its sequence variants and variable modification states are thought to play a role in the dynamic and long term regulation of genes.

core component of the nucleosome. Nucleosomes wrap and compress DNA into chromatin, limiting DNA's accessibility to cellular machinery that requires DNA as a template. Thus, histones play central roles in transcriptional regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated by a complex set of histone post-translational modifications (also known as the histone code) and nucleosome remodeling. Miscellaneous This histone is present only in mammals and is enriched for acetylation of Lys-15 and dimethylation of Lys-10 (H3K9me2).

Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. This structure consists of approximately 146 bp of DNA wrapped around a nucleosome, an octamer composed of pairs of each of the four core histones (H2A, H2B, H3, and H4). The chromatin fiber is further compacted through the interaction of a linker histone, H1, with the DNA between the nucleosomes to form higher order chromatin structures. This gene is intronless and encodes a replication-dependent histone that is a member of the histone H3 family. Transcripts from this gene lack polyA tails; instead, they contain a palindromic termination element. This gene is found in the large histone gene cluster on chromosome 6p22-p21.3.