Three-dimensional solution structure of Acanthamoeba profilin-I.
We have determined a medium resolution three-dimensional solution structure of Acanthamoeba profilin-I by multidimensional nuclear magnetic resonance spectroscopy. This 13-kD actin binding protein consists of a five stranded antiparallel beta sheet flanked by NH2- and COOH-terminal helices on one face and by a third helix and a two stranded beta sheet on the other face. Data from actin-profilin cross-linking experiments and the localization of conserved residues between profilins in different phyla indicate that actin binding occurs on the molecular face occupied by the terminal helices. The other face of the molecule contains the residues that differ between Acanthamoeba profilins-I and II and may be important in determining the difference in polyphosphoinositide binding between these isoforms. This suggests that lipids and actin bind to different faces of the molecule.
Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
V K
VK
Vinson
S J
SJ
Archer
E E
EE
Lattman
T D
TD
Pollard
D A
DA
Torchia
D000048:Acanthamoeba / Q000737:chemistry* / Q000378:metabolism; D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D003285:Contractile Proteins; D007091:Image Processing, Computer-Assisted; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008840:Microfilament Proteins / Q000737:chemistry*; D008969:Molecular Sequence Data; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism; D051304:Profilins; D012996:Solutions
D000199:Actins; D003285:Contractile Proteins; D008840:Microfilament Proteins; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D051304:Profilins; D012996:Solutions