PR00024

HOMEOBOX

PRINTS entry
Member databasePRINTS
PRINTS typedomain
Short nameHOMEOBOX

Description
Imported from IPR020479

This entry represents the homeodomain (HD), a protein domain of approximately 60 residues that usually binds DNA. It is encoded by the homeobox sequence
[3, 4]
, which was first identified in a number of Drosophila homeotic and segmentation proteins, but is now known to be well-conserved in many other animals, including vertebrates
[2, 1]
. Proteins containing HDs are likely to play an important role in development - most are known to be sequence-specific DNA-binding transcription factors. This domain folds into a globular structure with three α-helices connected by two short loops that harbour a hydrophobic core. The second and third form a helix-turn-helix (HTH) motif, which make intimate contacts with the DNA: while the first helix of this motif helps to stabilise the structure, the second helix binds to DNA via a number of hydrogen bonds and hydrophobic interactions, which occur between specific side chains and the exposed bases and thymine methyl groups within the major groove of the DNA
[3, 4]
. One particularity of the HTH motif in some of these proteins arises from the stereo-chemical requirement for glycine in the turn (position 9 of the motif), which is needed to avoid steric interference of the β-carbon with the main chain: for cro and repressor proteins the glycine appears to be mandatory, while for many of the homeotic and other DNA-binding proteins the requirement is relaxed.

References
Imported from IPR020479

1.The homeobox in perspective. Gehring WJ. Trends Biochem. Sci. 17, 277-80, (1992). View articlePMID: 1357790

2.The structure and function of the homeodomain. Scott MP, Tamkun JW, Hartzell GW 3rd. Biochim. Biophys. Acta 989, 25-48, (1989). View articlePMID: 2568852

3.Homeodomain proteins: an update. Burglin TR, Affolter M. Chromosoma 125, 497-521, (2016). PMID: 26464018

4.Classification and nomenclature of all human homeobox genes. Holland PW, Booth HA, Bruford EA. BMC Biol 5, 47, (2007). View articlePMID: 17963489

Further reading

5. A comprehensive classification and evolutionary analysis of plant homeobox genes. Mukherjee K, Brocchieri L, Burglin TR. Mol. Biol. Evol. 26, 2775-94, (2009). View articlePMID: 19734295

Supplementary References

Integrated to
This website requires cookies, and the limited processing of your personal data in order to function. By using the site you are agreeing to this as outlined in our Privacy Notice and Terms of Use.