2B9C

Structure of tropomyosin's mid-region: bending and binding sites for actin

2B9C の概要

• エントリーDOI: 10.2210/pdb2b9c/pdb
• 分子名称: striated-muscle alpha tropomyosin (2 entities in total)
• 機能のキーワード: alpha-helix, coiled coil, alanine, axial stagger, radius, side-chain packing, crystal packing, temperature factor, cardiomyopathy, elongated protein, contractile protein
• 由来する生物種: Rattus norvegicus (Norway rat)
• 細胞内の位置: Cytoplasm, cytoskeleton : P04692
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 34266.52

構造登録者

Brown, J.H.,Zhou, Z.,Reshetnikova, L.,Robinson, H.,Yammani, R.D.,Tobacman, L.S.,Cohen, C. (登録日: 2005-10-11, 公開日: 2006-01-03, 最終更新日: 2024-10-30)

主引用文献

Brown, J.H.,Zhou, Z.,Reshetnikova, L.,Robinson, H.,Yammani, R.D.,Tobacman, L.S.,Cohen, C.
Structure of the mid-region of tropomyosin: Bending and binding sites for actin.
Proc.Natl.Acad.Sci.Usa, 102:18878-18883, 2005

PubMed Abstract: Tropomyosin is a two-chain alpha-helical coiled coil whose periodic interactions with the F-actin helix are critical for thin filament stabilization and the regulation of muscle contraction. Here we deduce the mechanical and chemical basis of these interactions from the 2.3-A-resolution crystal structure of the middle three of tropomyosin's seven periods. Geometrically specific bends of the coiled coil, produced by clusters of core alanines, and variable bends about gaps in the core, produced by isolated alanines, occur along the molecule. The crystal packing is notable in signifying that the functionally important fifth period includes an especially favorable protein-binding site, comprising an unusual apolar patch on the surface together with surrounding charged residues. Based on these and other results, we have constructed a specific model of the thin filament, with the N-terminal halves of each period (i.e., the so-called "alpha zones") of tropomyosin axially aligned with subdomain 3 of each monomer in F-actin.

PubMed: 16365313
DOI: 10.1073/pnas.0509269102

実験手法

X-RAY DIFFRACTION (2.3 Å)