Mutagenesis of human profilin locates its poly(L-proline)-binding site to a hydrophobic patch of aromatic amino acids.
The actin-binding protein, profilin, contains a src-homology (SH) 3-like fold (Schutt, C.E. et al., submitted), and its tight interaction with poly(L-proline) is reminiscent of the binding activity exhibited by SH3-domains. Here we demonstrate that replacements of aromatic amino acids in a hydrophobic patch on the surface of the profilin molecule abolish its poly(L-proline)-binding capacity. However, the location of this hydrophobic patch is found in another region of the molecule than that displaying structural similarities with SH3 domains.
Björkegren
C
C
Department of Zoological Cell Biology, Stockholm University, Sweden.
Rozycki
M
M
Schutt
C E
CE
Lindberg
U
U
Karlsson
R
R
D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D003285:Contractile Proteins; D006801:Humans; D008840:Microfilament Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016296:Mutagenesis; D010455:Peptides / Q000378:metabolism*; D051304:Profilins; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012441:Saccharomyces cerevisiae
D000596:Amino Acids; D003285:Contractile Proteins; D008840:Microfilament Proteins; C495738:PFN1 protein, human; D010455:Peptides; D051304:Profilins; D011994:Recombinant Proteins; C011083:polyproline