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1m4j
From Proteopedia
(New page: 200px<br /><applet load="1m4j" size="450" color="white" frame="true" align="right" spinBox="true" caption="1m4j, resolution 1.60Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1m4j.jpg|left|200px]]<br /><applet load="1m4j" size=" | + | [[Image:1m4j.jpg|left|200px]]<br /><applet load="1m4j" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1m4j, resolution 1.60Å" /> | caption="1m4j, resolution 1.60Å" /> | ||
'''CRYSTAL STRUCTURE OF THE N-TERMINAL ADF-H DOMAIN OF MOUSE TWINFILIN ISOFORM-1'''<br /> | '''CRYSTAL STRUCTURE OF THE N-TERMINAL ADF-H DOMAIN OF MOUSE TWINFILIN ISOFORM-1'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Twinfilin is an evolutionarily conserved actin monomer-binding protein | + | Twinfilin is an evolutionarily conserved actin monomer-binding protein that regulates cytoskeletal dynamics in organisms from yeast to mammals. It is composed of two actin-depolymerization factor homology (ADF-H) domains that show approximately 20% sequence identity to ADF/cofilin proteins. In contrast to ADF/cofilins, which bind both G-actin and F-actin and promote filament depolymerization, twinfilin interacts only with G-actin. To elucidate the molecular mechanisms of twinfilin-actin monomer interaction, we determined the crystal structure of the N-terminal ADF-H domain of twinfilin and mapped its actin-binding site by site-directed mutagenesis. This domain has similar overall structure to ADF/cofilins, and the regions important for actin monomer binding in ADF/cofilins are especially well conserved in twinfilin. Mutagenesis studies show that the N-terminal ADF-H domain of twinfilin and ADF/cofilins also interact with actin monomers through similar interfaces, although the binding surface is slightly extended in twinfilin. In contrast, the regions important for actin-filament interactions in ADF/cofilins are structurally different in twinfilin. This explains the differences in actin-interactions (monomer versus filament binding) between twinfilin and ADF/cofilins. Taken together, our data show that the ADF-H domain is a structurally conserved actin-binding motif and that relatively small structural differences at the actin interfaces of this domain are responsible for the functional variation between the different classes of ADF-H domain proteins. |
==About this Structure== | ==About this Structure== | ||
| - | 1M4J is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http:// | + | 1M4J is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M4J OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Falck, S.]] | [[Category: Falck, S.]] | ||
[[Category: Lappalainen, P.]] | [[Category: Lappalainen, P.]] | ||
| - | [[Category: Merckel, M | + | [[Category: Merckel, M C.]] |
| - | [[Category: Ojala, P | + | [[Category: Ojala, P J.]] |
| - | [[Category: Paavilainen, V | + | [[Category: Paavilainen, V O.]] |
[[Category: Pohl, E.]] | [[Category: Pohl, E.]] | ||
[[Category: Wilmanns, M.]] | [[Category: Wilmanns, M.]] | ||
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[[Category: pair of alpha-helices]] | [[Category: pair of alpha-helices]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:51:24 2008'' |
Revision as of 11:51, 21 February 2008
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CRYSTAL STRUCTURE OF THE N-TERMINAL ADF-H DOMAIN OF MOUSE TWINFILIN ISOFORM-1
Overview
Twinfilin is an evolutionarily conserved actin monomer-binding protein that regulates cytoskeletal dynamics in organisms from yeast to mammals. It is composed of two actin-depolymerization factor homology (ADF-H) domains that show approximately 20% sequence identity to ADF/cofilin proteins. In contrast to ADF/cofilins, which bind both G-actin and F-actin and promote filament depolymerization, twinfilin interacts only with G-actin. To elucidate the molecular mechanisms of twinfilin-actin monomer interaction, we determined the crystal structure of the N-terminal ADF-H domain of twinfilin and mapped its actin-binding site by site-directed mutagenesis. This domain has similar overall structure to ADF/cofilins, and the regions important for actin monomer binding in ADF/cofilins are especially well conserved in twinfilin. Mutagenesis studies show that the N-terminal ADF-H domain of twinfilin and ADF/cofilins also interact with actin monomers through similar interfaces, although the binding surface is slightly extended in twinfilin. In contrast, the regions important for actin-filament interactions in ADF/cofilins are structurally different in twinfilin. This explains the differences in actin-interactions (monomer versus filament binding) between twinfilin and ADF/cofilins. Taken together, our data show that the ADF-H domain is a structurally conserved actin-binding motif and that relatively small structural differences at the actin interfaces of this domain are responsible for the functional variation between the different classes of ADF-H domain proteins.
About this Structure
1M4J is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
Structural conservation between the actin monomer-binding sites of twinfilin and actin-depolymerizing factor (ADF)/cofilin., Paavilainen VO, Merckel MC, Falck S, Ojala PJ, Pohl E, Wilmanns M, Lappalainen P, J Biol Chem. 2002 Nov 8;277(45):43089-95. Epub 2002 Aug 30. PMID:12207032
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