Histone H4 is one of the core histone proteins involved in organizing DNA into nucleosomes. It is a small globular protein with a structured histone fold domain and an unstructured N-terminal tail, like the other core histones. The histone fold domain is highly conserved amongst histone H4 variants and forms a histone octamer core when H4 interacts with its partner histones, H2A, H2B, and H3. The N-terminal tail of histone H4 is unstructured and protrudes from the nucleosome core. This tail is rich in lysine and arginine residues, which can undergo various post-translational modifications, such as acetylation, methylation, phosphorylation, and ubiquitylation. These modifications are essential for regulating chromatin structure and gene expression. Histone H4, along with its partner histones (H2A, H2B, and H3), contributes to the formation of the histone octamer core within the nucleosome. This core structure serves as a scaffold for wrapping DNA around, compacting the long DNA strands into a chromatin fiber. The interactions between histone H4 and DNA are vital for maintaining the stability of the nucleosome. Histone H4 is therefore central to the compaction of chromatin, folding DNA into higher-order structures within the nucleus. The degree of chromatin compaction can be regulated through various post-translational modifications on histone H4 and other histones. Histone H4 is a major target for various post-translational modifications that regulate chromatin structure and gene expression. For example, acetylation of specific lysine residues on histone H4 is associated with gene activation, whilst methylation and ubiquitylation can have varying effects on gene expression. Modifications of histone H4 are involved in transcriptional regulation. Specific patterns of histone modifications on H4 can serve as signals for the recruitment of transcriptional activators or repressors. These modifications can promote or inhibit gene expression by altering chromatin accessibility and the binding of transcription factors to DNA. Histone H4 is also associated with DNA repair processes. Upon DNA damage, histone H4 can undergo various modifications to facilitate the recruitment of DNA repair factors to the damaged sites. Additionally, histone modifications on H4 can mark such DNA damage sites thereby promoting repair processes. During cell division, histone H4 undergoes extensive modifications, including phosphorylation, contributing to the condensation of chromosomes during mitosis. Phosphorylation of histone H4, particularly at serine 1 and serine 47, contributes to the compaction of chromosomes, proper alignment of sister chromatids, and the maintenance of chromatin structure during mitosis. Phosphorylation thus results in chromatin compaction, ensuring the proper segregation of chromosomes during mitosis. Finally, histone H4 and its modifications can contribute to epigenetic inheritance. Specific patterns of histone modifications on H4 can mark genes for activation or repression, helping to maintain cell identity and regulate tissue-specific gene expression. Thus, histone H4 is a core histone protein with a structured histone fold domain and an N-terminal tail like other core histones, which plays a central role in chromatin structure and gene regulation. Histone H4 contributes to nucleosome formation, chromatin compaction, epigenetic regulation, transcriptional regulation, DNA repair, chromosome condensation during mitosis, and epigenetic inheritance. We offer a comprehensive product range of research tools for studying Histone H4, including Histone H4 antibodies, and Histone H4R78me1 antibodies. Explore our full Histone H4 product range below and discover more, for less. Alternatively, you can explore our Unmodified, Methylated, and Acetylated product ranges.