Histone H1.1 (H1.1)

Histone H1.1 is a member of the H1 linker histone family, a group of non-core histone proteins in eukaryotic chromatin that bind to the DNA between nucleosomes, known as linker DNA, and play a crucial role in stabilizing higher-order chromatin structures[1][3]. Unlike core histones (H2A, H2B, H3, H4), H1 is not part of the nucleosome bead but binds at the entry and exit points of DNA on the nucleosome, promoting chromatin fiber compaction and organization[1][3]. The H1 family comprises several subtypes—including H1.1—characterized by a central globular domain and highly variable terminal tails[1][3]. H1.1 contributes to the regulation of gene expression, chromatin dynamics, and modulation of DNA accessibility by controlling the folding of chromatin and acting as both a positive and negative regulator of transcription, depending on context[1][3]. Its biological roles are further influenced by posttranslational modifications such as phosphorylation, methylation, and acetylation, which regulate its activity during processes like the cell cycle and embryogenesis[3]. While essential for chromatin architecture, there are no current drugs that target H1.1 directly, and it is not considered a canonical therapeutic target or druggable receptor[3]. Deficiency or overexpression of H1.1 can lead to structural and functional chromatin abnormalities, highlighting its fundamental but non-specialized cellular role[1][3].

Other names

H1-1H1F1HIST1H1AH1.1H1aHistone H1aH1AHIST1histone H1.1H1 histone family, member 1histone 1, H1ahistone H1ahistone cluster 1 H1 family member ahistone cluster 1, H1a