|
|
| Line 1: |
Line 1: |
| [[Image:1exe.gif|left|200px]] | | {{Seed}} |
| | [[Image:1exe.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1exe| PDB=1exe | SCENE= }} | | {{STRUCTURE_1exe| PDB=1exe | SCENE= }} |
|
| |
|
| '''SOLUTION STRUCTURE OF A MUTANT OF TRANSCRIPTION FACTOR 1.'''
| | ===SOLUTION STRUCTURE OF A MUTANT OF TRANSCRIPTION FACTOR 1.=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| An NMR solution structure of a mutant of the homodimer protein transcription factor 1, TF1-G15/I32 (22 kDa), has been solved to atomic resolution, with 23 final structures that converge to an r.m. s.d. of 0.78 A. The overall shape of TF1-G15/I32 remains similar to that of the wild-type protein and other type II DNA-binding proteins. Each monomer has two N-terminal alpha-helices separated by a short loop, followed by a three-stranded beta-sheet, whose extension between the second and third beta-strands forms an antiparallel beta-ribbon arm, leading to a C-terminal third alpha-helix that is severely kinked in the middle. Close examination of the structure of TF1-G15/I32 reveals why it is more stable and binds DNA more tightly than does its wild-type counterpart. The dimeric core, consisting of the N-terminal helices and the beta-sheets, is more tightly packed, and this might be responsible for its increased thermal stability. The DNA-binding domain, composed of the top face of the beta-sheet, the beta-ribbon arms and the C-terminal helices, is little changed from wild-type TF1. Rather, the enhancement in DNA affinity must be due almost exclusively to the creation of an additional DNA-binding site at the side of the dimer by changes affecting helices 1 and 2: helix 2 of TF1-G15/I32 is one residue longer than helix 2 of the wild-type protein, bends inward, and is both translationally and rotationally displaced relative to helix 1. This rearrangement creates a longer, narrower fissure between the V-shaped N-terminal helices and exposes additional positively charged surface at each side of the dimer.
| | The line below this paragraph, {{ABSTRACT_PUBMED_10993726}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 10993726 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_10993726}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| 1EXE is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Spiroplasma_phage_4 Spiroplasma phage 4]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EXE OCA]. | | 1EXE is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Spiroplasma_phage_4 Spiroplasma phage 4]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EXE OCA]. |
|
| |
|
| ==Reference== | | ==Reference== |
| Line 29: |
Line 33: |
| [[Category: Dna-bending protein]] | | [[Category: Dna-bending protein]] |
| [[Category: Dna-binding]] | | [[Category: Dna-binding]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 15:38:03 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 1 02:10:00 2008'' |
