HMGNs: The enhancer charmers

• Published in: BioEssays Vol. 38; no. 3; pp. 226 - 231
• Main Authors: Martinez de Paz, Alexia, Ausio, Juan
• Format: Journal Article
• Language: English
• Published: United States Published for ICSU Press by Cambridge University Press 01.03.2016; Blackwell Publishing Ltd; Wiley Subscription Services, Inc
• Subjects: Animals; chromatin; deoxyribonuclease I; DNase I hypersensitive sites; Enhancer Elements, Genetic; enhancers; enhancers; high mobility group nucleosome‐binding proteins; Gene Expression Regulation; genes; high mobility group nucleosome-binding proteins; histones; HMGN Proteins - physiology; Humans; nucleosomes; Promoter Regions, Genetic; serine; transcription; transcription (genetics); Transcription, Genetic; vertebrates; transcription; chromatin; enhancers; high mobility group nucleosome-binding proteins; DNase I hypersensitive sites
• ISSN: 0265-9247; 1521-1878
• DOI: 10.1002/bies.201500157

The DNase I hypersensitive sites (DHSs) of chromatin constitute one of the best landmarks of eukaryotic genes that are poised and/or activated for transcription. For over 35 years, the high‐mobility group nucleosome‐binding chromosomal proteins HMGN1 and HMGN2 have been shown to play a role in the establishment of these chromatin‐accessible domains at transcriptional regulatory elements, namely promoters and enhancers. The critical presence of HMGNs at enhancers, as highlighted by a recent publication, suggests a role for them in the structural and functional fine‐tuning of the DHSs in vertebrates. As we review here, while preferentially out‐competing histone H1 binding and invading neighbor nucleosomes, HMGNs may also modulate histone H3 at serine 10 (H3S10ph), which plays an important role in enhancer function and transcriptional initiation.