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3dw8

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Revision as of 05:08, 25 December 2014

Structure of a Protein Phosphatase 2A Holoenzyme with B55 subunit

Structural highlights

3dw8 is a 8 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
NonStd Res:	, , , ,
Gene:	PPP2R1A (Homo sapiens), PPP2R2A (Homo sapiens), PPP2CA (Homo sapiens)
Activity:	Phosphoprotein phosphatase, with EC number 3.1.3.16
Resources:	FirstGlance, OCA, RCSB, PDBsum

Function

[2AAA_HUMAN] The PR65 subunit of protein phosphatase 2A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit. Required for proper chromosome segregation and for centromeric localization of SGOL1 in mitosis.^[1] [PP2AA_HUMAN] PP2A is the major phosphatase for microtubule-associated proteins (MAPs). PP2A can modulate the activity of phosphorylase B kinase casein kinase 2, mitogen-stimulated S6 kinase, and MAP-2 kinase. Cooperates with SGOL2 to protect centromeric cohesin from separase-mediated cleavage in oocytes specifically during meiosis I (By similarity). Can dephosphorylate SV40 large T antigen and p53/TP53. Activates RAF1 by dephosphorylating it at 'Ser-259'.^[2] ^[3] ^[4] [2ABA_HUMAN] The B regulatory subunit might modulate substrate selectivity and catalytic activity, and also might direct the localization of the catalytic enzyme to a particular subcellular compartment.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Protein phosphatase 2A (PP2A) regulates many essential aspects of cellular physiology. Members of the regulatory B/B55/PR55 family are thought to play a key role in the dephosphorylation of Tau, whose hyperphosphorylation contributes to Alzheimer's disease. The underlying mechanisms of the PP2A-Tau connection remain largely enigmatic. Here, we report the complete reconstitution of a Tau dephosphorylation assay and the crystal structure of a heterotrimeric PP2A holoenzyme involving the regulatory subunit Balpha. We show that Balpha specifically and markedly facilitates dephosphorylation of the phosphorylated Tau in our reconstituted assay. The Balpha subunit comprises a seven-bladed beta propeller, with an acidic, substrate-binding groove located in the center of the propeller. The beta propeller latches onto the ridge of the PP2A scaffold subunit with the help of a protruding beta hairpin arm. Structure-guided mutagenesis studies revealed the underpinnings of PP2A-mediated dephosphorylation of Tau.

Structure of a protein phosphatase 2A holoenzyme: insights into B55-mediated Tau dephosphorylation.,Xu Y, Chen Y, Zhang P, Jeffrey PD, Shi Y Mol Cell. 2008 Sep 26;31(6):873-85. PMID:18922469^[5]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Tang Z, Shu H, Qi W, Mahmood NA, Mumby MC, Yu H. PP2A is required for centromeric localization of Sgo1 and proper chromosome segregation. Dev Cell. 2006 May;10(5):575-85. Epub 2006 Mar 30. PMID:16580887 doi:10.1016/j.devcel.2006.03.010
↑ Hsu W, Zeng L, Costantini F. Identification of a domain of Axin that binds to the serine/threonine protein phosphatase 2A and a self-binding domain. J Biol Chem. 1999 Feb 5;274(6):3439-45. PMID:9920888
↑ Abraham D, Podar K, Pacher M, Kubicek M, Welzel N, Hemmings BA, Dilworth SM, Mischak H, Kolch W, Baccarini M. Raf-1-associated protein phosphatase 2A as a positive regulator of kinase activation. J Biol Chem. 2000 Jul 21;275(29):22300-4. PMID:10801873 doi:10.1074/jbc.M003259200
↑ Watkins GR, Wang N, Mazalouskas MD, Gomez RJ, Guthrie CR, Kraemer BC, Schweiger S, Spiller BW, Wadzinski BE. Monoubiquitination promotes calpain cleavage of the protein phosphatase 2A (PP2A) regulatory subunit alpha4, altering PP2A stability and microtubule-associated protein phosphorylation. J Biol Chem. 2012 Jul 13;287(29):24207-15. doi: 10.1074/jbc.M112.368613. Epub, 2012 May 21. PMID:22613722 doi:10.1074/jbc.M112.368613
↑ Xu Y, Chen Y, Zhang P, Jeffrey PD, Shi Y. Structure of a protein phosphatase 2A holoenzyme: insights into B55-mediated Tau dephosphorylation. Mol Cell. 2008 Sep 26;31(6):873-85. PMID:18922469 doi:http://dx.doi.org/10.1016/j.molcel.2008.08.006

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/3dw8"

@@ Line 9: / Line 9: @@
 <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=3dw8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3dw8 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3dw8 RCSB], [http://www.ebi.ac.uk/pdbsum/3dw8 PDBsum]</span></td></tr>
 </table>
+== Function ==
+[[http://www.uniprot.org/uniprot/2AAA_HUMAN 2AAA_HUMAN]] The PR65 subunit of protein phosphatase 2A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit. Required for proper chromosome segregation and for centromeric localization of SGOL1 in mitosis.<ref>PMID:16580887</ref>  [[http://www.uniprot.org/uniprot/PP2AA_HUMAN PP2AA_HUMAN]] PP2A is the major phosphatase for microtubule-associated proteins (MAPs). PP2A can modulate the activity of phosphorylase B kinase casein kinase 2, mitogen-stimulated S6 kinase, and MAP-2 kinase. Cooperates with SGOL2 to protect centromeric cohesin from separase-mediated cleavage in oocytes specifically during meiosis I (By similarity). Can dephosphorylate SV40 large T antigen and p53/TP53. Activates RAF1 by dephosphorylating it at 'Ser-259'.<ref>PMID:9920888</ref> <ref>PMID:10801873</ref> <ref>PMID:22613722</ref>  [[http://www.uniprot.org/uniprot/2ABA_HUMAN 2ABA_HUMAN]] The B regulatory subunit might modulate substrate selectivity and catalytic activity, and also might direct the localization of the catalytic enzyme to a particular subcellular compartment.
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]

3dw8

From Proteopedia

Revision as of 05:08, 25 December 2014

Structure of a Protein Phosphatase 2A Holoenzyme with B55 subunit

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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