Deciphering HMGB1: Across a spectrum of DNA and nucleosome dynamics

Cell Biol Int. 2024 Nov 17. doi: 10.1002/cbin.12260. Online ahead of print.

Abstract

HMGB1 is the most abundant nonhistone nuclear protein, which has been widely studied for its roles in the cytoplasm as an autophagy mediator and in the extracellular matrix as an inflammatory molecule. Studies concerning HMGB1's actual role and its binding within the nucleus are inadequate. Through this in vitro study, we aimed to discern the binding parameters of HMGB1 with various types of DNA, nucleosomes, and chromatin. HMGB1 binds differentially to different DNA, with a high affinity for altered DNA structures such as triplex and bulge DNA. Remodelling of nucleosome by CHD7 remodeller was negatively impacted by the binding of HMGB1. We also found that HMGB1 binds to the linker DNA of chromatin. Findings from this study shed light on the diverse roles HMGB1 may play in transcription, gene expression, viral replication, CHARGE syndrome and so forth.

Keywords: CHD7; chromatin; nucleosome; protein–DNA interactions; remodelling.