Related Experiment Video
Updated: Dec 27, 2025

Isolating Myofibrils from Skeletal Muscle Biopsies and Determining Contractile Function with a Nano-Newton Resolution Force Transducer
Published on: May 7, 2020
Differences in stability and calcium sensitivity of the Ig domains in titin's N2A region
Colleen M Kelly1,2, Sophia Manukian1, Emily Kim1
1Chemistry Department, University of Massachusetts Lowell, Lowell, Massachusetts, USA.
Abstract:
Titin is a large filamentous protein that spans half a sarcomere, from Z-disk to M-line. The N2A region within the titin molecule exists between the proximal immunoglobulin (Ig) region and the PEVK region and protein-protein interactions involving this region are required for normal muscle function. The N2A region consists of four Ig domains (I80-I83) with a 105 amino acid linker region between I80 and I81 that has a helical nature. Using chemical stability measurements, we show that predicted differences between the adjacent Ig domains (I81-I83) correlate with experimentally determined differences in chemical stability and refolding kinetics. Our work further shows that I83 has the lowest ΔGunfolding , which is increased in the presence of calcium (pCa 4.3), indicating that Ca2+ plays a role in stabilizing this immunoglobulin domain. The characteristics of N2A's three Ig domains provide insight into the stability of the binding sites for proteins that interact with the N2A region. This work also provides insights into how Ca2+ might influence binding events involving N2A.
More Related Videos
07:02Analyzing the α-Actinin Network in Human iPSC-Derived Cardiomyocytes Using Single Molecule Localization Microscopy
Published on: November 3, 2020
10:45Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement
Published on: July 26, 2017
Related Concept Videos
The Sarcomere
Each...
Tension Response at Adherens Junctions
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin...
The Structure of Intermediate Filaments
Intermediate...
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
Introduction to Actin
Overview of Myosin Structure and Function