1quq
From Proteopedia
(New page: 200px<br /> <applet load="1quq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1quq, resolution 2.5Å" /> '''COMPLEX OF REPLICATI...) |
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| - | [[Image:1quq.gif|left|200px]]<br /> | + | [[Image:1quq.gif|left|200px]]<br /><applet load="1quq" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1quq" size=" | + | |
caption="1quq, resolution 2.5Å" /> | caption="1quq, resolution 2.5Å" /> | ||
'''COMPLEX OF REPLICATION PROTEIN A SUBUNITS RPA14 AND RPA32'''<br /> | '''COMPLEX OF REPLICATION PROTEIN A SUBUNITS RPA14 AND RPA32'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Replication protein A (RPA), the eukaryote single-stranded DNA-binding | + | Replication protein A (RPA), the eukaryote single-stranded DNA-binding protein (SSB), is a heterotrimer. The largest subunit, RPA70, which harbours the major DNA-binding activity, has two DNA-binding domains that each adopt an OB-fold. The complex of the two smaller subunits, RPA32 and RPA14, has weak DNA-binding activity but the mechanism of DNA binding is unknown. We have determined the crystal structure of the proteolytic core of RPA32 and RPA14, which consists of the central two-thirds of RPA32 and the entire RPA14 subunit. The structure revealed that RPA14 and the central part of RPA32 are structural homologues. Each subunit contains a central OB-fold domain, which also resembles the DNA-binding domains in RPA70; an N-terminal extension that interacts with the central OB-fold domain; and a C-terminal helix that mediate heterodimerization via a helix-helix interaction. The OB-fold of RPA32, but not RPA14, possesses additional similarity to the RPA70 DNA-binding domains, supporting a DNA-binding role for RPA32. The discovery of a third and fourth OB-fold in RPA suggests that the quaternary structure of SSBs, which in Bacteria and Archaea are also tetramers of OB-folds, is conserved in evolution. The structure also suggests a mechanism for RPA trimer formation. |
==About this Structure== | ==About this Structure== | ||
| - | 1QUQ is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http:// | + | 1QUQ is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QUQ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bochkarev, A.]] | [[Category: Bochkarev, A.]] | ||
[[Category: Bochkareva, E.]] | [[Category: Bochkareva, E.]] | ||
| - | [[Category: Edwards, A | + | [[Category: Edwards, A M.]] |
[[Category: Frappier, L.]] | [[Category: Frappier, L.]] | ||
[[Category: ob-fold]] | [[Category: ob-fold]] | ||
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[[Category: ssdna-binding]] | [[Category: ssdna-binding]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:43:54 2008'' |
Revision as of 12:43, 21 February 2008
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COMPLEX OF REPLICATION PROTEIN A SUBUNITS RPA14 AND RPA32
Overview
Replication protein A (RPA), the eukaryote single-stranded DNA-binding protein (SSB), is a heterotrimer. The largest subunit, RPA70, which harbours the major DNA-binding activity, has two DNA-binding domains that each adopt an OB-fold. The complex of the two smaller subunits, RPA32 and RPA14, has weak DNA-binding activity but the mechanism of DNA binding is unknown. We have determined the crystal structure of the proteolytic core of RPA32 and RPA14, which consists of the central two-thirds of RPA32 and the entire RPA14 subunit. The structure revealed that RPA14 and the central part of RPA32 are structural homologues. Each subunit contains a central OB-fold domain, which also resembles the DNA-binding domains in RPA70; an N-terminal extension that interacts with the central OB-fold domain; and a C-terminal helix that mediate heterodimerization via a helix-helix interaction. The OB-fold of RPA32, but not RPA14, possesses additional similarity to the RPA70 DNA-binding domains, supporting a DNA-binding role for RPA32. The discovery of a third and fourth OB-fold in RPA suggests that the quaternary structure of SSBs, which in Bacteria and Archaea are also tetramers of OB-folds, is conserved in evolution. The structure also suggests a mechanism for RPA trimer formation.
About this Structure
1QUQ is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The crystal structure of the complex of replication protein A subunits RPA32 and RPA14 reveals a mechanism for single-stranded DNA binding., Bochkarev A, Bochkareva E, Frappier L, Edwards AM, EMBO J. 1999 Aug 16;18(16):4498-504. PMID:10449415
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