1bpv

From Proteopedia

Revision as of 09:42, 20 November 2007

TITIN MODULE A71 FROM HUMAN CARDIAC MUSCLE, NMR, 50 STRUCTURES

Overview

BACKGROUND: Titin is a huge protein ( approximately 3 MDa) that is present, in the contractile unit (sarcomere) of striated muscle and has a key role, in muscle assembly and elasticity. Titin is mainly composed of two types, of module (type I and II). Type I modules are found exclusively in the, region of titin localised in the A band, where they are arranged in a, super-repeat pattern that correlates with the ultrastructure of the thick, filament. No structure of a titin type I module has been reported so far., RESULTS: We have determined the structure of a representative type I, module, A71, using nuclear magnetic resonance (NMR) spectroscopy. The, structure has the predicted fibronectin type III fold. Titin-specific, conserved residues are either located at the putative module-module, interfaces or along one side of the protein surface. Several proline, residues that contribute to two stretches in a polyproline II helix, conformation are solvent-exposed and line up as a continuous ribbon, extending over more than two-thirds of the module surface. Homology models, of the type I module N-terminal to A71 (A70) and the double module A70-A71, were used to discuss possible intermodule interactions and their role in, module-module orientation. CONCLUSIONS: As residues at the module-module, interfaces are highly conserved, we speculate that similar interactions, govern all of the interfaces between type I modules in titin. This, conservation would lead to a regular multiple array of similar surface, structures. Such an arrangement would allow arrays of contiguous type I, modules to expose multiple proline stretches in a highly regular way and, these may act as binding sites for other thick filament proteins.

About this Structure

1BPV is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.

Reference

The three-dimensional structure of a type I module from titin: a prototype of intracellular fibronectin type III domains., Goll CM, Pastore A, Nilges M, Structure. 1998 Oct 15;6(10):1291-302. PMID:9782056

Page seeded by OCA on Tue Nov 20 11:49:24 2007