1lcu
| |||||||
| , resolution 3.5Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , and | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Polylysine Induces an Antiparallel Actin Dimer that Nucleates Filament Assembly: Crystal Structure at 3.5 A Resolution
OverviewOverview
An antiparallel actin dimer has been proposed to be an intermediate species during actin filament nucleation. We now show that latrunculin A, a marine natural product that inhibits actin polymerization, arrests polylysine-induced nucleation at the level of an antiparallel dimer, resulting in its accumulation. These dimers, when composed of pyrene-labeled actin subunits, give rise to a fluorescent excimer, permitting detection during polymerization in vitro. We report the crystallographic structure of the polylysine-actin-latrunculin A complex at 3.5-A resolution. The non-crystallographic contact is consistent with a dimeric structure and confirms the antiparallel orientation of its subunits. The crystallographic contacts reveal that the mobile DNase I binding loop of one subunit of a symmetry-related antiparallel actin dimer is partially stabilized in the interface between the two subunits of a second antiparallel dimer. These results provide a potential explanation for the paradoxical nucleation of actin filaments that have exclusively parallel subunits by a dimer containing antiparallel subunits.
About this StructureAbout this Structure
1LCU is a Single protein structure of sequence from Oryctolagus cuniculus. Full crystallographic information is available from OCA.
ReferenceReference
Polylysine induces an antiparallel actin dimer that nucleates filament assembly: crystal structure at 3.5-A resolution., Bubb MR, Govindasamy L, Yarmola EG, Vorobiev SM, Almo SC, Somasundaram T, Chapman MS, Agbandje-McKenna M, McKenna R, J Biol Chem. 2002 Jun 7;277(23):20999-1006. Epub 2002 Apr 3. PMID:11932258
Page seeded by OCA on Sun Mar 23 12:36:33 2008