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1le8
From Proteopedia
(New page: 200px<br /><applet load="1le8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1le8, resolution 2.30Å" /> '''Crystal Structure of...) |
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| - | [[Image:1le8.jpg|left|200px]]<br /><applet load="1le8" size=" | + | [[Image:1le8.jpg|left|200px]]<br /><applet load="1le8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1le8, resolution 2.30Å" /> | caption="1le8, resolution 2.30Å" /> | ||
'''Crystal Structure of the MATa1/MATalpha2-3A Heterodimer Bound to DNA Complex'''<br /> | '''Crystal Structure of the MATa1/MATalpha2-3A Heterodimer Bound to DNA Complex'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Triply mutated MATalpha2 protein, alpha2-3A, in which all three major | + | Triply mutated MATalpha2 protein, alpha2-3A, in which all three major groove-contacting residues are mutated to alanine, is defective in binding DNA alone or in complex with Mcm1 yet binds with MATa1 with near wild-type affinity and specificity. To gain insight into this unexpected behavior, we determined the crystal structure of the a1/alpha2-3A/DNA complex. The structure shows that the triple mutation causes a collapse of the alpha2-3A/DNA interface that results in a reorganized set of alpha2-3A/DNA contacts, thereby enabling the mutant protein to recognize the wild-type DNA sequence. Isothermal titration calorimetry measurements reveal that a much more favorable entropic component stabilizes the a1/alpha2-3A/DNA complex than the alpha2-3A/DNA complex. The combined structural and thermodynamic studies provide an explanation of how partner proteins influence the sequence specificity of a DNA binding protein. |
==About this Structure== | ==About this Structure== | ||
| - | 1LE8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http:// | + | 1LE8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LE8 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Ke, A.]] | [[Category: Ke, A.]] | ||
| - | [[Category: Mathias, J | + | [[Category: Mathias, J R.]] |
| - | [[Category: Vershon, A | + | [[Category: Vershon, A K.]] |
[[Category: Wolberger, C.]] | [[Category: Wolberger, C.]] | ||
[[Category: isothermal titration calorimetry]] | [[Category: isothermal titration calorimetry]] | ||
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[[Category: protein-dna complex]] | [[Category: protein-dna complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:44:14 2008'' |
Revision as of 11:44, 21 February 2008
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Crystal Structure of the MATa1/MATalpha2-3A Heterodimer Bound to DNA Complex
Overview
Triply mutated MATalpha2 protein, alpha2-3A, in which all three major groove-contacting residues are mutated to alanine, is defective in binding DNA alone or in complex with Mcm1 yet binds with MATa1 with near wild-type affinity and specificity. To gain insight into this unexpected behavior, we determined the crystal structure of the a1/alpha2-3A/DNA complex. The structure shows that the triple mutation causes a collapse of the alpha2-3A/DNA interface that results in a reorganized set of alpha2-3A/DNA contacts, thereby enabling the mutant protein to recognize the wild-type DNA sequence. Isothermal titration calorimetry measurements reveal that a much more favorable entropic component stabilizes the a1/alpha2-3A/DNA complex than the alpha2-3A/DNA complex. The combined structural and thermodynamic studies provide an explanation of how partner proteins influence the sequence specificity of a DNA binding protein.
About this Structure
1LE8 is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Structural and thermodynamic characterization of the DNA binding properties of a triple alanine mutant of MATalpha2., Ke A, Mathias JR, Vershon AK, Wolberger C, Structure. 2002 Jul;10(7):961-71. PMID:12121651
Page seeded by OCA on Thu Feb 21 13:44:14 2008
