helix-loop-helix

English

Basic helix-loop-helix

Etymology

From helix + loop + helix. The term got its name from its distinct physical geometry; two alpha helices separated and connected by a flexible chain of amino acids known as a "loop", allowing the helices to pack together tightly.

Noun

helix-loop-helix (plural helix-loop-helices, abbreviation HLH)

1. (biochemistry, genetics) A structural motif where two alpha helices are connected by a highly flexible amino acid loop, allowing the helices to pack together. Usually requires forming a dimer with another HLH protein before binding DNA.

Related terms

• helix-turn-helix
• heterodimerization
• homodimerization
• leucine zipper
• myogenesis
• zinc finger

Further reading

• Sequence motif on Wikipedia.Wikipedia
• Structural motif on Wikipedia.Wikipedia
• Protein domain on Wikipedia.Wikipedia
• Transcription factor on Wikipedia.Wikipedia
• Myc on Wikipedia.Wikipedia