View source for 1fnt


==CRYSTAL STRUCTURE OF THE 20S PROTEASOME FROM YEAST IN COMPLEX WITH THE PROTEASOME ACTIVATOR PA26 FROM TRYPANOSOME BRUCEI AT 3.2 ANGSTROMS RESOLUTION==
<StructureSection load='1fnt' size='340' side='right'caption='[[1fnt]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1fnt]] is a 42 chain structure with sequence from [https://en.wikipedia.org/wiki/Atcc_18824 Atcc 18824]. The December 2004 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Ubiquitin''  by David S. Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2004_12 10.2210/rcsb_pdb/mom_2004_12]. The October 2013 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Proteasome''  by David Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2013_10 10.2210/rcsb_pdb/mom_2013_10]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FNT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1FNT FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1ryp|1ryp]], [[1avo|1avo]]</div></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Proteasome_endopeptidase_complex Proteasome endopeptidase complex], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.25.1 3.4.25.1] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1fnt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fnt OCA], [https://pdbe.org/1fnt PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1fnt RCSB], [https://www.ebi.ac.uk/pdbsum/1fnt PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1fnt ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/PSA1_YEAST PSA1_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSB2_YEAST PSB2_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSA4_YEAST PSA4_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSA3_YEAST PSA3_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSB7_YEAST PSB7_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. PRE3 and PRE4 are necessary for the peptidyl-glutamyl-peptide-hydrolyzing activity.<ref>PMID:8381431</ref>  [[https://www.uniprot.org/uniprot/PSB5_YEAST PSB5_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. This unit is responsible of the chymotrypsin-like activity of the proteasome and is one of the principal target of the proteasome inhibitor bortezomib.  This subunit is necessary for chymotryptic activity and degradation of ubiquitinated proteins. [[https://www.uniprot.org/uniprot/PSA2_YEAST PSA2_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSB4_YEAST PSB4_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. This subunit has a chymotrypsin-like activity. [[https://www.uniprot.org/uniprot/PSB6_YEAST PSB6_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSA6_YEAST PSA6_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSA7_YEAST PSA7_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. [[https://www.uniprot.org/uniprot/PSB1_YEAST PSB1_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. PRE3 and PRE4 are necessary for the peptidyl-glutamyl-peptide-hydrolyzing activity.  This subunit is necessary for the peptidylglutamyl-peptide hydrolyzing activity. [[https://www.uniprot.org/uniprot/PSB3_YEAST PSB3_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. This subunit may participate in the trypsin-like activity of the enzyme complex. [[https://www.uniprot.org/uniprot/PSA5_YEAST PSA5_YEAST]] The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity. 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fn/1fnt_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1fnt ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Most of the non-lysosomal proteolysis that occurs in eukaryotic cells is performed by a nonspecific and abundant barrel-shaped complex called the 20S proteasome. Substrates access the active sites, which are sequestered in an internal chamber, by traversing a narrow opening (alpha-annulus) that is blocked in the unliganded 20S proteasome by amino-terminal sequences of alpha-subunits. Peptide products probably exit the 20S proteasome through the same opening. 11S regulators (also called PA26 (ref. 4), PA28 (ref. 5) and REG) are heptamers that stimulate 20S proteasome peptidase activity in vitro and may facilitate product release in vivo. Here we report the co-crystal structure of yeast 20S proteasome with the 11S regulator from Trypanosoma brucei (PA26). PA26 carboxy-terminal tails provide binding affinity by inserting into pockets on the 20S proteasome, and PA26 activation loops induce conformational changes in alpha-subunits that open the gate separating the proteasome interior from the intracellular environment. The reduction in processivity expected for an open conformation of the exit gate may explain the role of 11S regulators in the production of ligands for major histocompatibility complex class I molecules.

Structural basis for the activation of 20S proteasomes by 11S regulators.,Whitby FG, Masters EI, Kramer L, Knowlton JR, Yao Y, Wang CC, Hill CP Nature. 2000 Nov 2;408(6808):115-20. PMID:11081519<ref>PMID:11081519</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1fnt" style="background-color:#fffaf0;"></div>

==See Also==
*[[Proteasome 3D structures|Proteasome 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Atcc 18824]]
[[Category: Large Structures]]
[[Category: Proteasome]]
[[Category: Proteasome endopeptidase complex]]
[[Category: RCSB PDB Molecule of the Month]]
[[Category: Ubiquitin]]
[[Category: Hill, C P]]
[[Category: Knowlton, J R]]
[[Category: Kramer, L]]
[[Category: Masters, E]]
[[Category: Wang, C C]]
[[Category: Whitby, F G]]
[[Category: Yao, Y]]
[[Category: 20s proteasome]]
[[Category: Antigen processing]]
[[Category: Cell adhesion]]
[[Category: Hydrolase-hydrolase activator complex]]
[[Category: Interferon induction]]
[[Category: Multicatalytic proteinase]]
[[Category: Protease]]
[[Category: Proteasome activator]]
[[Category: Protein degradation]]