You are a researcher who studies the molecular structure of the ryanodine recept
ID: 54842 • Letter: Y
Question
You are a researcher who studies the molecular structure of the ryanodine receptor (RyR) proteins. You've discovered a mutation in the gene encoding RyR that is associated with early infant death. In order to study the mutation, you genetically engineer a laboratory mouse so that it expresses only this mutant form of the gene encoding the ryanodine receptor protein. The mutation interferes with the ability of the protein to open in response to calcium ion binding, but does not confer any other structural or functional changes. Write a paragraph describing the what you would predict would happen to contraction of skeletal and cardiac muscle in the mouse, and explaining why the mutation could be fatal in infants.
Explanation / Answer
Ryanodine(RyRs) receptors belong to a class of intracellular calcium channels present in excitable cells such as nervs and muscles. Stimulation of ryanodine receptors releases calcium from the stores of sarcoplasmic reticulum (in muscles) and endoplasmic reticulum. RyR1 receptor is expressed in skeletal muslces, and RyR2 is expressed in cardiac muscles.
Mutation in Ryanodine receptors impairs the release of calcium from the intracellular stores, which impirs muscle contraction. As calcium is essential for muscle contraction, mutations in Ryanodie receptors could be fatal due to inability of cardiac muscle and skeletal muscle functioning (contraction).
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.