H1-2

Histone H1 protein binds to linker DNA between nucleosomes forming the macromolecular structure known as the chromatin fiber. Histone H1-2 is required for the condensation of nucleosome chains into higher-order structured fibers. Compared to other histone H1 variants, H1-2 plays an essential role in nucleosome condensation: its absence leads to global chromatin decompaction, which is not observed when depleting other histone H1 variants. Histone H1-2 also acts as a histone reader: specifically recognizes and binds histone H3 trimethylated at 'lys-27' (H3K27me3). Histones H1 also promote formation of the H3K27me3 mark by the PRC2/EED-EZH2 complex, possibly by facilitating restoration of H3K27me3 post-replication. Together with histone H1-3, histone H1-2 acts as a regulator of splicing, most specifically exon skipping and intron retention events: histone H1-2 has a high affinity for exons and regulates splicing by affecting RNA polymerase II (RNAPII) elongation. Also acts as a regulator of individual gene transcription through chromatin remodeling, nucleosome spacing and DNA methylation..

Function from UniProtKB (P16403), read 2026-09-23. CC BY 4.0.