TATA-Binding Protein: Difference between revisions
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TATA-binding protein uses two types of interactions to recognize and hold the TATA sequence, as seen in this structure [[1ytb]]. First, it has a string of lysine and arginine amino acids that <scene name='TATA-Binding_Protein/Lysine_and_arginine_phosphate/1'>interact with the phosphate groups</scene> of the DNA. This glues the protein to the DNA. Second, the protein uses specially-placed amino acids to interact with DNA bases. four <scene name='TATA-Binding_Protein/Phe_asp_pairs/2'> phenylalanine amino acids </scene>jam into the DNA minor groove and form the kinks that bend the DNA. The use of β sheet regions to recognize the minor groove of the DNA stands in contrast to the more common DNA recognition strategy where the protein uses an α helix to recognize the major groove of the DNA. There are also two symmetrical <scene name='TATA-Binding_Protein/Phe_asp_pairs/3'> asparagine amino acids </scene>that form hydrogen bonds at the very center. The combination of the unusual flexibility of TATA DNA sequences and these specific hydrogen bonds allows TATA-binding protein to recognize the proper sequence. | TATA-binding protein uses two types of interactions to recognize and hold the TATA sequence, as seen in this structure [[1ytb]]. First, it has a string of lysine and arginine amino acids that <scene name='TATA-Binding_Protein/Lysine_and_arginine_phosphate/1'>interact with the phosphate groups</scene> of the DNA. This glues the protein to the DNA. Second, the protein uses specially-placed amino acids to interact with DNA bases. four <scene name='TATA-Binding_Protein/Phe_asp_pairs/2'> phenylalanine amino acids </scene>jam into the DNA minor groove and form the kinks that bend the DNA. The use of β sheet regions to recognize the minor groove of the DNA stands in contrast to the more common DNA recognition strategy where the protein uses an α helix to recognize the major groove of the DNA. There are also two symmetrical <scene name='TATA-Binding_Protein/Phe_asp_pairs/3'> asparagine amino acids </scene>that form hydrogen bonds at the very center. The combination of the unusual flexibility of TATA DNA sequences and these specific hydrogen bonds allows TATA-binding protein to recognize the proper sequence. | ||
As you are looking at these structures yourself, notice that TATA-binding protein, even though it is composed of a single protein chain, is composed of <scene name='TATA-Binding_Protein/Symmetrical/ | As you are looking at these structures yourself, notice that TATA-binding protein, even though it is composed of a single protein chain, is composed of <scene name='TATA-Binding_Protein/Symmetrical/4'>two symmetrical halves</scene>. This symmetry is easily seen in the two pairs of phenylalanines and the two asparagines. It is thought that an ancient gene duplication created this protein by combining two copies of the same gene. | ||
== Acknowledgements == | == Acknowledgements == | ||
*Content adapted with permission from David S. Goodsell Molecule of the Month on the TATA-Binding Protein [http://mgl.scripps.edu/people/goodsell/pdb/pdb67 Molecule of the Month] | *Content adapted with permission from David S. Goodsell Molecule of the Month on the TATA-Binding Protein [http://mgl.scripps.edu/people/goodsell/pdb/pdb67 Molecule of the Month] | ||
