1a0k
From Proteopedia
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==Overview== | ==Overview== | ||
| - | BACKGROUND: Profilins are small eukaryotic proteins involved in modulating | + | BACKGROUND: Profilins are small eukaryotic proteins involved in modulating the assembly of actin microfilaments in the cytoplasm. They are able to bind both phosphatidylinositol-4,5-bisphosphate and poly-L-proline (PLP) and thus play a critical role in signaling pathways. Plant profilins are of interest because immunological cross-reactivity between pollen and human profilin may be the cause of hay fever and broad allergies to pollens. RESULTS: The determination of the Arabidopsis thaliana profilin isoform I structure, using multiwavelength anomalous diffraction (MAD) to obtain structure-factor phases, is reported here. The structure of Arabidopsis profilin is similar to that of previously determined profilin structures. Conserved amino acid residues in profilins from plants, mammals, and lower eukaryotes are critically important in dictating the geometry of the PLP-binding site and the overall polypeptide fold. The main feature distinguishing plant profilins from other profilins is a solvent-filled pocket located in the most variable region of the fold. CONCLUSIONS: Comparison of the structures of SH3 domains with those of profilins from three distinct sources suggests that the mode of PLP binding may be similar. A comparison of three profilin structures from different families reveals only partial conservation of the actin-binding surface. The proximity of the semi-conserved actin-binding site and the binding pocket characteristic of plant profilins suggests that epitopes encompassing both features are responsible for the cross-reactivity of antibodies between human and plant profilins thought to be responsible for type I allergies. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Huddler, D.]] | [[Category: Huddler, D.]] | ||
| - | [[Category: Junior, R | + | [[Category: Junior, R Shigeta.]] |
[[Category: Lindberg, U.]] | [[Category: Lindberg, U.]] | ||
| - | [[Category: Schutt, C | + | [[Category: Schutt, C E.]] |
[[Category: actin-binding]] | [[Category: actin-binding]] | ||
[[Category: cytoskeleton]] | [[Category: cytoskeleton]] | ||
[[Category: profilin]] | [[Category: profilin]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:39:32 2008'' |
Revision as of 09:39, 21 February 2008
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PROFILIN I FROM ARABIDOPSIS THALIANA
Overview
BACKGROUND: Profilins are small eukaryotic proteins involved in modulating the assembly of actin microfilaments in the cytoplasm. They are able to bind both phosphatidylinositol-4,5-bisphosphate and poly-L-proline (PLP) and thus play a critical role in signaling pathways. Plant profilins are of interest because immunological cross-reactivity between pollen and human profilin may be the cause of hay fever and broad allergies to pollens. RESULTS: The determination of the Arabidopsis thaliana profilin isoform I structure, using multiwavelength anomalous diffraction (MAD) to obtain structure-factor phases, is reported here. The structure of Arabidopsis profilin is similar to that of previously determined profilin structures. Conserved amino acid residues in profilins from plants, mammals, and lower eukaryotes are critically important in dictating the geometry of the PLP-binding site and the overall polypeptide fold. The main feature distinguishing plant profilins from other profilins is a solvent-filled pocket located in the most variable region of the fold. CONCLUSIONS: Comparison of the structures of SH3 domains with those of profilins from three distinct sources suggests that the mode of PLP binding may be similar. A comparison of three profilin structures from different families reveals only partial conservation of the actin-binding surface. The proximity of the semi-conserved actin-binding site and the binding pocket characteristic of plant profilins suggests that epitopes encompassing both features are responsible for the cross-reactivity of antibodies between human and plant profilins thought to be responsible for type I allergies.
About this Structure
1A0K is a Single protein structure of sequence from Arabidopsis thaliana. Known structural/functional Sites: , and . Full crystallographic information is available from OCA.
Reference
The crystal structure of a major allergen from plants., Thorn KS, Christensen HE, Shigeta R, Huddler D, Shalaby L, Lindberg U, Chua NH, Schutt CE, Structure. 1997 Jan 15;5(1):19-32. PMID:9016723
Page seeded by OCA on Thu Feb 21 11:39:32 2008
