TY - JOUR
T1 - Oligomerization of profilins from birch, man and yeast. Profilin, a ligand for itself?
AU - Mittermann, Irene
AU - Fetrow, Jacquelyn S.
AU - Schaak, Diana L.
AU - Almo, Steven C.
AU - Kraft, Dietrich
AU - Heberle-Bors, Erwin
AU - Valenta, Rudolf
N1 - Funding Information:
&p.2: wledgements This study was supported in part by grants S06703 and T11688-Gen of the Austrian Science Fund, by the ICP programme of the Austrian Ministry of Research and Transports and by a grant from Pharmacia and Upjohn, Uppsala, Sweden. We thank Michael Duchêne for stimulating discussions.
PY - 1998
Y1 - 1998
N2 - Profilins are structurally well conserved low molecular weight (12-15 kDa) eukaryotic proteins which interact with a variety of physiological ligands: (1) cytoskeletal components, e.g., actin; (2) polyphosphoinositides, e.g., phosphatidylinositol-4,5-bisphosphate; (3) proline-rich proteins, e.g., formin homology proteins and vasodilatator-stimulated phosphoprotein. Profilins may thus link the microfilament system with signal transduction pathways. Plant profilins have recently been shown to be highly crossreactive allergens which bind to IgE antibodies of allergic patients and thus cause symptoms of type I allergy. We expressed and purified from Escherichia coli profilins from birch pollen (Betula verrucosa), humans (Homo sapiens) and yeast (Schizosaccharomyces pombe) and demonstrated that each of these profilins is able to form stable homo- and heteropolymers via disulphide bonds in vitro. Circular dichroism analysis of oxidized (polymeric) and reduced (monomeric) birch pollen profilin indicates that the two states have similar secondary structures. Using 125I-labeled birch pollen, yeast and human profilin in overlay experiments, we showed that disulphide bond formation between profilins can be disrupted under reducing conditions, while reduced as well as oxidized profilin states bind to actin and profilin-specific antibodies. Exposure of profilin to oxidizing conditions, such as when pollen profilins are liberated on the surface of the mucosa of atopic patients, may lead to profilin polymerization and thus contribute to the sensitization capacity of profilin as an allergen.
AB - Profilins are structurally well conserved low molecular weight (12-15 kDa) eukaryotic proteins which interact with a variety of physiological ligands: (1) cytoskeletal components, e.g., actin; (2) polyphosphoinositides, e.g., phosphatidylinositol-4,5-bisphosphate; (3) proline-rich proteins, e.g., formin homology proteins and vasodilatator-stimulated phosphoprotein. Profilins may thus link the microfilament system with signal transduction pathways. Plant profilins have recently been shown to be highly crossreactive allergens which bind to IgE antibodies of allergic patients and thus cause symptoms of type I allergy. We expressed and purified from Escherichia coli profilins from birch pollen (Betula verrucosa), humans (Homo sapiens) and yeast (Schizosaccharomyces pombe) and demonstrated that each of these profilins is able to form stable homo- and heteropolymers via disulphide bonds in vitro. Circular dichroism analysis of oxidized (polymeric) and reduced (monomeric) birch pollen profilin indicates that the two states have similar secondary structures. Using 125I-labeled birch pollen, yeast and human profilin in overlay experiments, we showed that disulphide bond formation between profilins can be disrupted under reducing conditions, while reduced as well as oxidized profilin states bind to actin and profilin-specific antibodies. Exposure of profilin to oxidizing conditions, such as when pollen profilins are liberated on the surface of the mucosa of atopic patients, may lead to profilin polymerization and thus contribute to the sensitization capacity of profilin as an allergen.
KW - Cytoskeleton
KW - Oligomerization
KW - Pollen
KW - Profilin
KW - Type I allergy
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U2 - 10.1007/s004970050140
DO - 10.1007/s004970050140
M3 - Article
AN - SCOPUS:0031729642
SN - 0934-0882
VL - 11
SP - 183
EP - 191
JO - Sexual Plant Reproduction
JF - Sexual Plant Reproduction
IS - 4
ER -