In contrast, a more diffuse localization was seen when non-fused GFP and MYBPC1 proteins containing corresponding MYBPC3 amino acid substitutions (R326Q, E334K) that cause hypertrophic cardiomyopathy were expressed.
The conclusion is the missense MYBPC3 mutation E334K destabilizes its protein through UPS and may contribute to cardiac dysfunction in HCM through impairment of the ubiquitin-proteasome system.