High mobility group box protein 4 (HMGB4)

High mobility group box protein 4 (HMGB4) is a mammalian-specific, non-histone chromatin protein and the least characterized member of the HMGB family. Unlike HMGB1–3, it lacks the typical acidic C-terminal tail, contains two HMG box domains, and is primarily expressed in testis and, to a lesser extent, in the brain[3][1][2]. HMGB4 localizes to chromatin and acts as a transcriptional repressor, modulating the expression of genes involved in neuronal and germ cell differentiation and influencing post-translational histone modifications. It binds DNA in a sequence-independent but structure-dependent manner, and is implicated in chromatin organization and gene regulation, especially during spermatogenesis and neuronal development[1][2][3][4][5]. Its expression pattern and functional studies suggest specialized roles in tissue-specific chromatin regulation. No approved drugs or therapeutic compounds directly target HMGB4, and its potential as a clinical biomarker or direct therapeutic target remains unexplored.

Other names

High mobility group protein B4HMGB4FLJ40388dJ1007G16.5HMG2-like

Not applicable (no direct drugs known; regulates chromatin accessibility and transcriptional repression[3][1])