Publication Date:
2009-01-23
Description:
Actin plays crucial parts in cell motility through a dynamic process driven by polymerization and depolymerization, that is, the globular (G) to fibrous (F) actin transition. Although our knowledge about the actin-based cellular functions and the molecules that regulate the G- to F-actin transition is growing, the structural aspects of the transition remain enigmatic. We created a model of F-actin using X-ray fibre diffraction intensities obtained from well oriented sols of rabbit skeletal muscle F-actin to 3.3 A in the radial direction and 5.6 A along the equator. Here we show that the G- to F-actin conformational transition is a simple relative rotation of the two major domains by about 20 degrees. As a result of the domain rotation, the actin molecule in the filament is flat. The flat form is essential for the formation of stable, helical F-actin. Our F-actin structure model provides the basis for understanding actin polymerization as well as its molecular interactions with actin-binding proteins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Oda, Toshiro -- Iwasa, Mitsusada -- Aihara, Tomoki -- Maeda, Yuichiro -- Narita, Akihiro -- England -- Nature. 2009 Jan 22;457(7228):441-5. doi: 10.1038/nature07685.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉X-ray Structural Analysis Research Team, RIKEN SPring-8 Center, RIKEN Harima Institute, 1-1-1, Kouto, Sayo, Hyogo 679-5148, Japan. toda@spring8.or.jp〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19158791" target="_blank"〉PubMed〈/a〉
Keywords:
Actins/*chemistry/*metabolism
;
Animals
;
Biopolymers/chemistry/metabolism
;
Cell Movement
;
Glutamine/metabolism
;
Hydrolysis
;
Magnetics
;
Models, Molecular
;
Muscle Contraction
;
Muscle, Skeletal/chemistry
;
Protein Structure, Quaternary
;
Protein Subunits/chemistry/metabolism
;
Rabbits
;
X-Ray Diffraction
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
