Related Experiment Video
Updated: Mar 20, 2026

A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
Toward Understanding the Molecular Bases of Stretch Activation: A STRUCTURAL COMPARISON OF THE TWO TROPONIN C
Domenico Sanfelice1, Máximo Sanz-Hernández2, Alfonso de Simone2
1From the Department of Clinical and Basic Neurosciences, Wohl Institute, King's College, London SE5 3RT, United Kingdom.
Abstract:
Muscles are usually activated by calcium binding to the calcium sensory protein troponin-C, which is one of the three components of the troponin complex. However, in cardiac and insect flight muscle activation is also produced by mechanical stress. Little is known about the molecular bases of this calcium-independent activation. In Lethocerus, a giant water bug often used as a model system because of its large muscle fibers, there are two troponin-C isoforms, called F1 and F2, that have distinct roles in activating the muscle. It has been suggested that this can be explained either by differences in structural features or by differences in the interactions with other proteins. Here we have compared the structural and dynamic properties of the two proteins and shown how they differ. We have also mapped the interactions of the F2 isoform with peptides spanning the sequence of its natural partner, troponin-I. Our data have allowed us to build a model of the troponin complex and may eventually help in understanding the specialized function of the F1 and F2 isoforms and the molecular mechanism of stretch activation.
More Related Videos
11:23Characterization at the Molecular Level using Robust Biochemical Approaches of a New Kinase Protein
Published on: June 30, 2019
10:31Detection of In Situ Protein-protein Complexes at the Drosophila Larval Neuromuscular Junction Using Proximity Ligation Assay
Published on: January 20, 2015
Related Concept Videos
Overview of Myosin Structure and Function
The Sarcomere
Each...
Actin and Myosin in Muscle Contraction
Introduction to Actin
Cytoskeletal Proteins in Bacteria
Excitation-Contraction Coupling in Skeletal Muscles
When an action...