1yrn

<StructureSection load='1yrn' size='340' side='right' caption='[[1yrn]], [[Resolution|resolution]] 2.50&Aring;' scene=''>

<table><tr><td colspan='2'>[[1yrn]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_18824 Atcc 18824]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YRN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1YRN FirstGlance]. <br>

</td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">MAT A1 RESIDUE 66-126 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=4932 ATCC 18824]), MAT ALPHA2 RESIDUE 128-210 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=4932 ATCC 18824])</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1yrn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yrn OCA], [http://pdbe.org/1yrn PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1yrn RCSB], [http://www.ebi.ac.uk/pdbsum/1yrn PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1yrn ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/MTAL2_YEAST MTAL2_YEAST]] Mating type proteins are sequence specific DNA-binding proteins that act as master switches in yeast differentiation by controlling gene expression in a cell type-specific fashion. Transcriptional corepressor that binds cooperatively with MCM1 to a 31-basepair DNA sequence termed the a-specific gene (asg) operator, to repress the transcription of a-cell-specific genes. Additionally, in a/alpha diploid cells, binds cooperatively with the A1 protein to a 21-basepair DNA sequence termed the haploid-specific gene (hsg) operator, to repress transcription of haploid-specific genes and of MATALPHA1.<ref>PMID:8664541</ref>

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== Publication Abstract from PubMed ==

The Saccharomyces cerevisiae MATa1 and MAT alpha 2 homeodomain proteins, which play a role in determining yeast cell type, form a heterodimer that binds DNA and represses transcription in a cell type-specific manner. Whereas the alpha 2 and a1 proteins on their own have only modest affinity for DNA, the a1/alpha 2 heterodimer binds DNA with high specificity and affinity. The three-dimensional crystal structure of the a1/alpha 2 homeodomain heterodimer bound to DNA was determined at a resolution of 2.5 A. The a1 and alpha 2 homeodomains bind in a head-to-tail orientation, with heterodimer contacts mediated by a 16-residue tail located carboxyl-terminal to the alpha 2 homeodomain. This tail becomes ordered in the presence of a1, part of it forming a short amphipathic helix that packs against the a1 homeodomain between helices 1 and 2. A pronounced 60 degree bend is induced in the DNA, which makes possible protein-protein and protein-DNA contacts that could not take place in a straight DNA fragment. Complex formation mediated by flexible protein-recognition peptides attached to stably folded DNA binding domains may prove to be a general feature of the architecture of other classes of eukaryotic transcriptional regulators.

Crystal structure of the MATa1/MAT alpha 2 homeodomain heterodimer bound to DNA.,Li T, Stark MR, Johnson AD, Wolberger C Science. 1995 Oct 13;270(5234):262-9. PMID:7569974<ref>PMID:7569974</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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<div class="pdbe-citations 1yrn" style="background-color:#fffaf0;"></div>

[[Category: Atcc 18824]]

[[Category: Johnson, A D]]

[[Category: Li, T]]

[[Category: Stark, M R]]

[[Category: Wolberger, C]]

[[Category: Complex]]

[[Category: Dna-binding protein]]