Correlation of Calmodulin Susceptibility and Cardiac Arrhythmia Mutations
Location
CSU Ballroom
Start Date
10-4-2018 10:00 AM
End Date
10-4-2018 11:30 AM
Student's Major
Chemistry and Geology
Student's College
Science, Engineering and Technology
Mentor's Name
Rebecca Moen
Mentor's Department
Chemistry and Geology
Mentor's College
Science, Engineering and Technology
Description
Calmodulin (CaM) is a is a calcium binding protein found in all muscle types in humans including cardiac muscle. CaM's role is to mediate intracellular calcium levels and modulate cardiac contractility by binding calcium ions as well as to a diverse set of targets including the calcium-release channel called the ryanodine receptor. CaM has been found to be susceptible to both site-specific methionine oxidation and disease-causing point mutations. A series of disease-causing point mutations lead to a congenital arrhythmia disorder catecholaminergic polymorphic ventricular tachycardia (CPVT) including mutants D95V, D129G, and F141L. Both oxidative modifications and CPVT mutations within the primary amino acid sequence of CaM decrease CaM's ability to bind calcium and affect the protein's stability and folding. CaM has a general dumbbell shaped structure with two globular domains, a N-terminal and C-terminal lobe, connected by a flexible alpha-helical linker. Each of these two globular domains bind two calcium ions. CPVT mutations negatively affect the ability of calcium binding to the C-lobe of the CaM which lead to a decrease in thermal stability of the protein (16). The correlation of between the CPVT mutation in CaM and oxidative susceptibly was investigated. Site-directed mutagenesis and recombinant protein overexpression was used to produce CaM which was purified using hydrophobic interaction chromatography. Changes in protein stability was monitored using ThermoFluor assays. Changes in CaM's stability and folding give insight into the affects of single amino acid point mutations on cardiac muscle contractility and how these mutations are linked to calcium in cardiac diseases.
Correlation of Calmodulin Susceptibility and Cardiac Arrhythmia Mutations
CSU Ballroom
Calmodulin (CaM) is a is a calcium binding protein found in all muscle types in humans including cardiac muscle. CaM's role is to mediate intracellular calcium levels and modulate cardiac contractility by binding calcium ions as well as to a diverse set of targets including the calcium-release channel called the ryanodine receptor. CaM has been found to be susceptible to both site-specific methionine oxidation and disease-causing point mutations. A series of disease-causing point mutations lead to a congenital arrhythmia disorder catecholaminergic polymorphic ventricular tachycardia (CPVT) including mutants D95V, D129G, and F141L. Both oxidative modifications and CPVT mutations within the primary amino acid sequence of CaM decrease CaM's ability to bind calcium and affect the protein's stability and folding. CaM has a general dumbbell shaped structure with two globular domains, a N-terminal and C-terminal lobe, connected by a flexible alpha-helical linker. Each of these two globular domains bind two calcium ions. CPVT mutations negatively affect the ability of calcium binding to the C-lobe of the CaM which lead to a decrease in thermal stability of the protein (16). The correlation of between the CPVT mutation in CaM and oxidative susceptibly was investigated. Site-directed mutagenesis and recombinant protein overexpression was used to produce CaM which was purified using hydrophobic interaction chromatography. Changes in protein stability was monitored using ThermoFluor assays. Changes in CaM's stability and folding give insight into the affects of single amino acid point mutations on cardiac muscle contractility and how these mutations are linked to calcium in cardiac diseases.
Recommended Citation
Hinde, Amanda. "Correlation of Calmodulin Susceptibility and Cardiac Arrhythmia Mutations." Undergraduate Research Symposium, Mankato, MN, April 10, 2018.
https://cornerstone.lib.mnsu.edu/urs/2018/poster-session-A/25
