high-mobility group

HMG proteins were originally isolated from mammalian cells, and named according to their electrophoretic mobility in polyacrylamide gels.{{cite book | author = Johns EB | title = The HMG chromosomal proteins | publisher = Academic Press | location = Boston | year = 1982 | isbn = 978-0-12-386050-7 }}

The HMG proteins are subdivided into 3 superfamilies each containing a characteristic functional domain:

• HMGA – contains an AT-hook domain
• HMGA1
• HMGA2
• HMGB – contains a HMG-box domain
• HMGB1
• HMGB2
• HMGB3
• HMGB4
• HMGN – contains a nucleosomal binding domain
• HMGN1
• HMGN2
• HMGN3
• HMGN4
• HMGN5

Proteins containing any of the above domains embedded in their sequence are known as HMG-motif proteins.

HMG-box proteins are found in a variety of eukaryotic organisms.

• SOX gene family
• Sex-Determining Region Y Protein
• SOX1, SOX2, etc.
• TCF/LEF family (T cell factor/lymphoid enhancer factor family)
• LEF1 (Lymphoid enhancer-binding factor 1)
• TCF7 (TCF-1)
• TCF7L1 (TCF-3)
• TCF7L2 (TCF-4)

HMG proteins are thought to play a significant role in various human disorders. Disruptions and rearrangements in the genes coding for some of the HMG proteins are associated with some common benign tumors. Antibodies to HMG proteins are found in patients with autoimmune diseases. The SRY gene on the Y Chromosome, responsible for male sexual differentiation, contains an HMG-Box domain. A member of the HMG family of proteins, HMGB1, has also been shown to have an extracellular activity as a chemokine, attracting neutrophils and mononuclear inflammatory cells to the infected liver.{{cite journal |vauthors=Sitia G, Iannacone M, Müller S, Bianchi ME, Guidotti LG | title = Treatment with HMGB1 inhibitors diminishes CTL-induced liver disease in HBV transgenic mice | journal = J. Leukoc. Biol. | volume = 81 | issue = 1 | pages = 100–7 |date=January 2007 | pmid = 16935945 | doi = 10.1189/jlb.0306173 | doi-access = free }} The high-mobility group protein such as HMO1 {{Cite journal |doi = 10.1093/nar/gku635|pmid = 25063301|pmc = 4132745|title = DNA bridging and looping by HMO1 provides a mechanism for stabilizing nucleosome-free chromatin|journal = Nucleic Acids Research|volume = 42|issue = 14|pages = 8996–9004|year = 2014|last1 = Murugesapillai|first1 = Divakaran|last2 = McCauley|first2 = Micah J.|last3 = Huo|first3 = Ran|last4 = Nelson Holte|first4 = Molly H.|last5 = Stepanyants|first5 = Armen|last6 = Maher|first6 = L. James|last7 = Israeloff|first7 = Nathan E.|last8 = Williams|first8 = Mark C.}} alters DNA architecture by binding, bending and looping. Furthermore, these HMG-box DNA-binding proteins increase the flexibility of the DNA upon binding.{{Cite journal | doi=10.1007/s12551-016-0236-4|title = Single-molecule studies of high-mobility group B architectural DNA bending proteins| journal=Biophysical Reviews| volume=9| pages=17–40|year = 2017|last1 = Murugesapillai|first1 = Divakaran| last2=McCauley| first2=Micah J.| last3=Maher| first3=L. James| last4=Williams| first4=Mark C.|issue = 1| pmc=5331113| pmid=28303166}}

In mammalian cells, the HMG non-histone proteins can modulate the activity of major DNA repair pathways including base excision repair, mismatch repair, nucleotide excision repair and double-strand break repair.Reeves R. High mobility group (HMG) proteins: Modulators of chromatin structure and DNA repair in mammalian cells. DNA Repair (Amst). 2015 Dec;36:122-136. doi: 10.1016/j.dnarep.2015.09.015. Epub 2015 Sep 16. PMID 26411874

• Gene regulatory network
• HMG-box
• Transcription factors

{{reflist}}

• [https://web.archive.org/web/20060928012928/http://www.informatics.jax.org/mgihome/nomen/genefamilies/hmgfamily.shtml HMG nomenclature home page]
• {{MeshName|High+Mobility+Group+Proteins}}

{{Transcription factors|g4}}

Category:Gene expression

Category:Transcription factors

{{genetics-stub}}