The roles of HMGB1 nuclear protein and its major domains in different biological fields

HMGB1 protein is an intracellular protein that translocated into the nucleus and regulates genes expression. HMGB1 plays multi-functional roles through recombination, transcriptional regulation, and inflammation. HMGB1 binds to cyclin-dependent kinase such as CDK2 that regulates the transcription of genes associated with the progression of cell cycle. In addition, HMGB1 as a novel cytokine plays major role in inflammation and arthritis. Recently, the role of HMGB1 protein as an adjuvant and stimulating both humoral and cellular immune responses has been proven in viral infections such as HIV-1 and influenza. Several studies indicated that Hp91, a HMGB1-derived peptide, stimulates efficiently DC maturation, and boosts the cellular and humoral immune responses in vivo. Our recent data also showed that the full length of HMGB1 gene, and Hp91 peptide could be an effective adjuvant in developing the therapeutic HPV DNA- and protein-based vaccines, respectively. In this review, the structure and functions of HMGB1 is described in molecular biology and medicine.