Rocket Launcher Mechanism of Collaborative Actin Assembly Defined by Single-Molecule Imaging

Interacting sets of actin assembly factors work together in cells, but the underlying mechanisms have remained obscure. We used triple-color single-molecule fluorescence microscopy to image the tumor suppressor adenomatous polyposis coli (APC) and the formin mDial during filament assembly. Complexes...

Full description

Saved in:
Bibliographic Details
Published in:Science (American Association for the Advancement of Science) 2012-06, Vol.336 (6085), p.1164-1168
Main Authors: Breitsprecher, Dennis, Jaiswal, Richa, Bombardier, Jeffrey P., Gould, Christopher J., Gelles, Jeff, Goode, Bruce L.
Format: Article
Language:English
Subjects:
Actin Cytoskeleton - metabolism
Actins
Actins - chemistry
Actins - metabolism
Adaptor Proteins, Signal Transducing - chemistry
Adaptor Proteins, Signal Transducing - metabolism
Adenomatous Polyposis Coli Protein - chemistry
Adenomatous Polyposis Coli Protein - metabolism
Animals
Assembly
Biological and medical sciences
Cell structures and functions
Cytoskeleton
Cytoskeleton, cytoplasm. Intracellular movements
Disassembly
Filaments
Fluorescence
Fundamental and applied biological sciences. Psychology
Imaging
Microfilaments
Microscopy
Microscopy, Fluorescence
Molecular and cellular biology
Molecules
Monomers
Nucleation
Peptide Fragments - chemistry
Peptide Fragments - metabolism
Polymerization
Profilins
Profilins - metabolism
Protein Binding
Protein Interaction Domains and Motifs
Protein Multimerization
Proteins
Rabbits
Rocket launchers
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Interacting sets of actin assembly factors work together in cells, but the underlying mechanisms have remained obscure. We used triple-color single-molecule fluorescence microscopy to image the tumor suppressor adenomatous polyposis coli (APC) and the formin mDial during filament assembly. Complexes consisting of APC, mDia1, and actin monomers initiated actin filament formation, overcoming inhibition by capping protein and profilin. Upon filament polymerization, the complexes separated, with mDia1 moving processively on growing barbed ends while APC remained at the site of nucleation. Thus, the two assembly factors directly interact to initiate filament assembly and then separate but retain independent associations with either end of the growing filament.
ISSN:0036-8075
1095-9203
DOI:10.1126/science.1218062