Dilated Cardiomyopathy (DCM) Is a Common Cause of Sudden Death

Multiple Choice

Dilated cardiomyopathy (DCM) is a common cause of sudden death and heart failure. Many mutations can cause DCM, but several of them are linked to the protein troponin, which is an essential protein that helps regulate muscle contraction in the heart.
-The A159E mutation causes an A amino acid to be replaced with an E amino acid (their structures are shown here) . What effects do you think the A159E mutation will have on the troponin protein?

A) The mutation will not affect troponin function since both the A and E amino acids are hydrophobic and thus the troponin structure will not be affected.
B) The mutation will probably make troponin more stable at low pH and at higher temperatures since the E amino acid is acidic.
C) Since the E amino acid is hydrophilic, it will try to be exposed on the surface of the protein and thus will disrupt the tertiary structure and potentially the function of troponin.
D) If the A amino acid is replaced by the basic E amino acid, then the secondary and tertiary structures will be affected and troponin will likely not fold correctly.