Histone H1.5: Proteins and Enzymes

Histones are nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber as they play a critical role in transcription regulation, DNA repair, DNA replication, and chromosomal stability. Histone H1.5 is a 207 amino acid long, 22 kDA protein encoded by the gene HIST1H1B (found on chromosome 6p22-p21.3) that lacks polyA tails and instead obtain palindromic termination elements. H1 histones are critical for the condensation of nucleosome chains into higher order structures. HIST1H1B has been investigated regarding breast cancer, measles, ataxia, t-cell leukemia, arthritis, alzheimer's diseases, lupus, and prostate cancer. It is active in apoptosis, histone modification, PKA signaling, and cell cycle chromosome condensation in prometaphase as it interacts with genes H3F3A, H3F3B, SIRT1, CDK2, and L3MNTL1.