– HMGN3 belongs to the HMGN family and is expressed in the kidney, lung, pancreas, testis, skeletal muscle, heart, thyroid gland, pituitary gland, prostate, and uterus. Members of the HMGN family bind to nucleosomes without any specificity for the underlying DNA sequence. They affect the global and local structure of chromatin, as well as the levels of histone modifications, and thus play a role in epigenetic regulation of gene expression. HMGN3 regulates the expression of the glucose transporter SLC2A2 by binding specifically to its promoter region and recruiting PDX1 and additional transcription factors. It also regulates the expression of SLC6A9, a glycine transporter that regulates the glycine concentration in synaptic junctions in the central nervous system, by binding to its transcription start site. Both insulin and glucagon levels can be affected by HMGN3. HMGN3 may play a role in ocular development and astrocyte function. It also modulates the expression of pancreatic genes involved in insulin secretion.