 |
PDBsum entry 1io0
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Protein binding
|
PDB id
|
|
|
|
1io0
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Crystal structure of the c-Terminal half of tropomodulin and structural basis of actin filament pointed-End capping.
|
|
|
Authors
|
|
I.Krieger,
A.Kostyukova,
A.Yamashita,
Y.Nitanai,
Y.Maéda.
|
|
|
Ref.
|
|
Biophys J, 2002,
83,
2716-2725.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Tropomodulin is the unique pointed-end capping protein of the actin-tropomyosin
filament. By blocking elongation and depolymerization, tropomodulin regulates
the architecture and the dynamics of the filament. Here we report the crystal
structure at 1.45-A resolution of the C-terminal half of tropomodulin (C20), the
actin-binding moiety of tropomodulin. C20 is a leucine-rich repeat domain, and
this is the first actin-associated protein with a leucine-rich repeat. Binding
assays suggested that C20 also interacts with the N-terminal fragment, M1-M2-M3,
of nebulin. Based on the crystal structure, we propose a model for C20 docking
to the actin subunit at the pointed end. Although speculative, the model is
consistent with the idea that a tropomodulin molecule competes with an actin
subunit for a pointed end. The model also suggests that interactions with
tropomyosin, actin, and nebulin are all possible sources of influences on the
dynamic properties of pointed-end capping by tropomodulin.
|
|
|
|
|
|
|
