Sandbox GGC1: Difference between revisions
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== Relevance == | == Relevance == | ||
Histone octamer containing two of H2A, H2B, H3 and H4 and the octamer wraps 147bp of DNA. H3.3 interacts with HIRA which is a chaperone and ZMYND11 when trimethylated at <scene name='75/752263/3wtp/2'>Lysine-36</scene> (color coded dark blue). HIRA can deposit histones of H3.3 in replicating and non replicating cells. Also in the HIRA complex, Anti slicing factors ASF1a and ASF1b are purified by H3.3. However, when there's a disappearance of HIRA which is responsible for H3.3 deposition, it can cause defects in the early stages of embryogenesis. ZMYND11 also known as BS69 can find H3.3 LYS 36 (H3.3K36me3) by the binding domain of chromatin <ref>https://www.pnas.org/content/112/22/6814</ref>. | Histone octamer containing two of H2A, H2B, H3 and H4 and the octamer wraps 147bp of DNA. H3.3 interacts with HIRA which is a chaperone and ZMYND11 when trimethylated at <scene name='75/752263/3wtp/2'>Lysine-36</scene> (color coded dark blue)<ref>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5446305/</ref>. HIRA can deposit histones of H3.3 in replicating and non replicating cells. Also in the HIRA complex, Anti slicing factors ASF1a and ASF1b are purified by H3.3. However, when there's a disappearance of HIRA which is responsible for H3.3 deposition, it can cause defects in the early stages of embryogenesis. ZMYND11 also known as BS69 can find H3.3 LYS 36 (H3.3K36me3) by the binding domain of chromatin <ref>https://www.pnas.org/content/112/22/6814</ref>. | ||
== Structural highlights == | == Structural highlights == | ||
[https://www.nature.com/articles/srep07115 CENP-A]is a centromere specific variant of Histone H3 and it's controlled in normal cells and its chromosome localization is heavily restricted in the centromere regions. It can be over expressed in cancer cells and also be mislocalized ectopically in the form of heterotypic nucleosomes containing H3.3 <ref>https://www.nature.com/articles/srep07115</ref>. In vitro, the human CENP-A nucleosomes can have two copies each of CENP-A, H2A, H2B and H4 histones <ref>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585026/</ref>.<scene name='75/752263/Arg_49/1'>ARG 49</scene> is located on H3.3 and is on the E chain (color coded light pink). The significance to this is that ARG 49 of Asf1 is maintained as threonine or glutamic acid. Histone H2B located on chains D and H (color coded dark blue), histone H2A type 1-B/E which is located chains C and G (also color coded dark blue),Histone H3-like centromeric protein A is located on chain A (color coded in the lightest blue),and Histone H4 is located on chains B and F (color coded medium blue) <ref>https://www.rcsb.org/structure/3WTP</ref>. | [https://www.nature.com/articles/srep07115 CENP-A]is a centromere specific variant of Histone H3 and it's controlled in normal cells and its chromosome localization is heavily restricted in the centromere regions. It can be over expressed in cancer cells and also be mislocalized ectopically in the form of heterotypic nucleosomes containing H3.3 <ref>https://www.nature.com/articles/srep07115</ref>. In vitro, the human CENP-A nucleosomes can have two copies each of CENP-A, H2A, H2B and H4 histones <ref>https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585026/</ref>.<scene name='75/752263/Arg_49/1'>ARG 49</scene> is located on H3.3 and is on the E chain (color coded light pink). The significance to this is that ARG 49 of Asf1 is maintained as threonine or glutamic acid. Histone H2B located on chains D and H (color coded dark blue), histone H2A type 1-B/E which is located chains C and G (also color coded dark blue),Histone H3-like centromeric protein A is located on chain A (color coded in the lightest blue),and Histone H4 is located on chains B and F (color coded medium blue) <ref>https://www.rcsb.org/structure/3WTP</ref>. | ||