This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

3q2b

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Current revision

Crystal Structure of an Actin Depolymerizing Factor

Structural highlights

3q2b is a 1 chain structure with sequence from Plasmodium falciparum HB3. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.6Å
Ligands:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

CADF1_PLAFX Not involved in actin polymerisation, instead functions to stimulate nucleotide exchange on monomeric actin and influence turnover of the small amount of cytosolic actin microfilaments. Essential for erythrocytic schizogony.^[1]

Publication Abstract from PubMed

Malaria parasite cell motility is a process that is dependent on the dynamic turnover of parasite-derived actin filaments. Despite its central role, actin's polymerization state is controlled by a set of identifiable regulators that is markedly reduced compared with those of other eukaryotic cells. In Plasmodium falciparum, the most virulent species that affects humans, this minimal repertoire includes two members of the actin-depolymerizing factor/cofilin (AC) family of proteins, P. falciparum actin-depolymerizing factor 1 (PfADF1) and P. falciparum actin-depolymerizing factor 2. This essential class of actin regulator is involved in the control of filament dynamics at multiple levels, from monomer binding through to filament depolymerization and severing. Previous biochemical analyses have suggested that PfADF1 sequesters monomeric actin but, unlike most eukaryotic counterparts, has limited potential to bind or depolymerize filaments. The molecular basis for these unusual properties and implications for parasite cell motility have not been established. Here we present the crystal structure of an apicomplexan AC protein, PfADF1. We show that PfADF1 lacks critical residues previously implicated as essential for AC-mediated actin filament binding and disassembly, having a substantially reduced filament-binding loop and C-terminal alpha4 helix. Despite this divergence in structure, we demonstrate that PfADF1 is capable of efficient actin filament severing. Furthermore, this severing occurs despite PfADF1's low binding affinity for filaments. Comparative structural analysis along with biochemical and microscopy evidence establishes that severing is reliant on the availability of an exposed basic residue in the filament-binding loop, a conserved minimal requirement that defines AC-mediated filament disassembly across eukaryotic cells.

Minimal requirements for actin filament disassembly revealed by structural analysis of malaria parasite actin-depolymerizing factor 1.,Wong W, Skau CT, Marapana DS, Hanssen E, Taylor NL, Riglar DT, Zuccala ES, Angrisano F, Lewis H, Catimel B, Clarke OB, Kershaw NJ, Perugini MA, Kovar DR, Gulbis JM, Baum J Proc Natl Acad Sci U S A. 2011 Jun 14;108(24):9869-74. Epub 2011 May 31. PMID:21628589^[2]

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

References

↑ Schuler H, Mueller AK, Matuschewski K. A Plasmodium actin-depolymerizing factor that binds exclusively to actin monomers. Mol Biol Cell. 2005 Sep;16(9):4013-23. Epub 2005 Jun 22. PMID:15975905 doi:http://dx.doi.org/10.1091/mbc.E05-02-0086
↑ Wong W, Skau CT, Marapana DS, Hanssen E, Taylor NL, Riglar DT, Zuccala ES, Angrisano F, Lewis H, Catimel B, Clarke OB, Kershaw NJ, Perugini MA, Kovar DR, Gulbis JM, Baum J. Minimal requirements for actin filament disassembly revealed by structural analysis of malaria parasite actin-depolymerizing factor 1. Proc Natl Acad Sci U S A. 2011 Jun 14;108(24):9869-74. Epub 2011 May 31. PMID:21628589 doi:10.1073/pnas.1018927108

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/3q2b"

@@ Line 3: / Line 3: @@
 <StructureSection load='3q2b' size='340' side='right'caption='[[3q2b]], [[Resolution|resolution]] 1.60&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[3q2b]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Plafx Plafx]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3Q2B OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3Q2B FirstGlance]. <br>
+<table><tr><td colspan='2'>[[3q2b]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Plasmodium_falciparum_HB3 Plasmodium falciparum HB3]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3Q2B OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3Q2B FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=TAR:D(-)-TARTARIC+ACID'>TAR</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.6&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=TAR:D(-)-TARTARIC+ACID'>TAR</scene></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=3q2b FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3q2b OCA], [https://pdbe.org/3q2b PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3q2b RCSB], [https://www.ebi.ac.uk/pdbsum/3q2b PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3q2b ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[https://www.uniprot.org/uniprot/CADF1_PLAFX CADF1_PLAFX]] Not involved in actin polymerisation, instead functions to stimulate nucleotide exchange on monomeric actin and influence turnover of the small amount of cytosolic actin microfilaments. Essential for erythrocytic schizogony.<ref>PMID:15975905</ref>
+[https://www.uniprot.org/uniprot/CADF1_PLAFX CADF1_PLAFX] Not involved in actin polymerisation, instead functions to stimulate nucleotide exchange on monomeric actin and influence turnover of the small amount of cytosolic actin microfilaments. Essential for erythrocytic schizogony.<ref>PMID:15975905</ref>
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==
@@ Line 23: / Line 24: @@
 </StructureSection>
 [[Category: Large Structures]]
-[[Category: Plafx]]
+[[Category: Plasmodium falciparum HB3]]
-[[Category: Baum, J]]
+[[Category: Baum J]]
-[[Category: Clarke, O B]]
+[[Category: Clarke OB]]
-[[Category: Gulbis, J M]]
+[[Category: Gulbis JM]]
-[[Category: Wong, W]]
+[[Category: Wong W]]
-[[Category: Actin]]
-[[Category: Actin regulator]]
-[[Category: Actin-binding protein]]

3q2b

From Proteopedia

Current revision

Crystal Structure of an Actin Depolymerizing Factor

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox