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Helix-Turn-Helix Motifs MeSH Descriptor Data 2026


MeSH Heading
Helix-Turn-Helix Motifs
Tree Number(s)
G02.111.570.820.709.275.500.360.360
Unique ID
D019077
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D019077
Annotation
do not confuse with HELIX-LOOP-HELIX MOTIFS
Scope Note
The first DNA-binding protein motif to be recognized. Helix-turn-helix motifs were originally identified in bacterial proteins but have since been found in hundreds of DNA-BINDING PROTEINS from both eukaryotes and prokaryotes. They are constructed from two alpha helices connected by a short extended chain of amino acids, which constitute the turn. The two helices are held at a fixed angle, primarily through interactions between the two helices. (From Alberts et al., Molecular Biology of the Cell, 3d ed, p408-9)
Entry Term(s)
HTH Motifs
Motifs, Helix-Turn-Helix
Previous Indexing
Amino Acid Sequence (1985-1994)
Helix-Loop-Helix Motifs (1994-1995)
Public MeSH Note
96; was see HELIX-LOOP-HELIX MOTIFS 1994-95
Online Note
use HELIX-LOOP-HELIX MOTIFS to search HELIX-TURN-HELIX MOTIFS 1994-95
History Note
96; was see HELIX-LOOP-HELIX MOTIFS 1994-95
Date Introduced
1996/01/01
Last Updated
2016/05/31
Helix-Turn-Helix Motifs Preferred
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