1dce
From Proteopedia
(New page: 200px<br /><applet load="1dce" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dce, resolution 2.0Å" /> '''CRYSTAL STRUCTURE OF ...) |
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| - | [[Image:1dce.gif|left|200px]]<br /><applet load="1dce" size=" | + | [[Image:1dce.gif|left|200px]]<br /><applet load="1dce" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dce, resolution 2.0Å" /> | caption="1dce, resolution 2.0Å" /> | ||
'''CRYSTAL STRUCTURE OF RAB GERANYLGERANYLTRANSFERASE FROM RAT BRAIN'''<br /> | '''CRYSTAL STRUCTURE OF RAB GERANYLGERANYLTRANSFERASE FROM RAT BRAIN'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Rab geranylgeranyltransferase (RabGGT) catalyzes the addition | + | BACKGROUND: Rab geranylgeranyltransferase (RabGGT) catalyzes the addition of two geranylgeranyl groups to the C-terminal cysteine residues of Rab proteins, which is crucial for membrane association and function of these proteins in intracellular vesicular trafficking. Unlike protein farnesyltransferase (FT) and type I geranylgeranyltransferase, which both prenylate monomeric small G proteins or short peptides, RabGGT can prenylate Rab only when Rab is in a complex with Rab escort protein (REP). RESULTS: The crystal structure of rat RabGGT at 2.0 A resolution reveals an assembly of four distinct structural modules. The beta subunit forms an alpha-alpha barrel that contains most of the residues in the active site. The alpha subunit consists of a helical domain, an immunoglobulin (Ig)-like domain, and a leucine-rich repeat (LRR) domain. The N-terminal region of the alpha subunit binds to the active site in the beta subunit; residue His2alpha directly coordinates a zinc ion. The prenyl-binding pocket of RabGGT is deeper than that in FT. CONCLUSIONS: LRR and Ig domains are often involved in protein-protein interactions; in RabGGT they might participate in the recognition and binding of REP. The binding of the N-terminal peptide of the alpha subunit to the active site suggests an autoinhibition mechanism that might contribute to the inability of RabGGT to recognize short peptides or Rab alone as its substrate. Replacement of residues Trp102beta and Tyr154beta in FT by Ser48beta and Leu99beta, respectively, in RabGGT largely determine the different lipid-binding specificities of the two enzymes. |
==About this Structure== | ==About this Structure== | ||
| - | 1DCE is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1DCE is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DCE OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Rattus norvegicus]] | [[Category: Rattus norvegicus]] | ||
[[Category: Deisenhofer, H.]] | [[Category: Deisenhofer, H.]] | ||
| - | [[Category: Seabra, M | + | [[Category: Seabra, M C.]] |
[[Category: Zhang, H.]] | [[Category: Zhang, H.]] | ||
[[Category: ZN]] | [[Category: ZN]] | ||
| - | [[Category: 2 | + | [[Category: 2 0 a resolution]] |
[[Category: alpha subunit]] | [[Category: alpha subunit]] | ||
[[Category: beta subunit]] | [[Category: beta subunit]] | ||
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[[Category: rab geranylgeranyltransferase]] | [[Category: rab geranylgeranyltransferase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:15:10 2008'' |
Revision as of 10:15, 21 February 2008
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CRYSTAL STRUCTURE OF RAB GERANYLGERANYLTRANSFERASE FROM RAT BRAIN
Overview
BACKGROUND: Rab geranylgeranyltransferase (RabGGT) catalyzes the addition of two geranylgeranyl groups to the C-terminal cysteine residues of Rab proteins, which is crucial for membrane association and function of these proteins in intracellular vesicular trafficking. Unlike protein farnesyltransferase (FT) and type I geranylgeranyltransferase, which both prenylate monomeric small G proteins or short peptides, RabGGT can prenylate Rab only when Rab is in a complex with Rab escort protein (REP). RESULTS: The crystal structure of rat RabGGT at 2.0 A resolution reveals an assembly of four distinct structural modules. The beta subunit forms an alpha-alpha barrel that contains most of the residues in the active site. The alpha subunit consists of a helical domain, an immunoglobulin (Ig)-like domain, and a leucine-rich repeat (LRR) domain. The N-terminal region of the alpha subunit binds to the active site in the beta subunit; residue His2alpha directly coordinates a zinc ion. The prenyl-binding pocket of RabGGT is deeper than that in FT. CONCLUSIONS: LRR and Ig domains are often involved in protein-protein interactions; in RabGGT they might participate in the recognition and binding of REP. The binding of the N-terminal peptide of the alpha subunit to the active site suggests an autoinhibition mechanism that might contribute to the inability of RabGGT to recognize short peptides or Rab alone as its substrate. Replacement of residues Trp102beta and Tyr154beta in FT by Ser48beta and Leu99beta, respectively, in RabGGT largely determine the different lipid-binding specificities of the two enzymes.
About this Structure
1DCE is a Protein complex structure of sequences from Rattus norvegicus with as ligand. Full crystallographic information is available from OCA.
Reference
Crystal structure of Rab geranylgeranyltransferase at 2.0 A resolution., Zhang H, Seabra MC, Deisenhofer J, Structure. 2000 Mar 15;8(3):241-51. PMID:10745007
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