Plant homeobox genes can be classified into 14 classes based on sequence differentiation and fusion with characteristic codomain sequences. Homeobox genes encode a typical DNA-binding domain of 60 amino acids, known as homeodomain. Typically, homeodomain folds into characteristic 3D structure containing three alpha-helices, of which the second and third form a helix-turn-helix motif.
The homeodomain motif is very similar in sequence and structure to domains in a wide range of DNA-binding proteins, including Myb proteins, GARP response regulators, human telomeric proteins (hTRF1) etc. This entry indicated a family which have a very homodomain like DNA binding domain.
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