Point Mutation in Luminal Loop 7 of Scap Blocks Interaction with Loop 1 and Abolishes Movement to Golgi *

Background: Scap controls cholesterol by transporting SREBPs from ER to Golgi in a sterolsensitive fashion. Two luminal loops of Scap (Loops 1 and 7) may play a regulatory role. Results: A point mutation in Scap Loop 7 prevents interaction with Loop 1 and abolishes ER exit. Conclusions: Scap movement and activation of SREBPs require Loop 1-7 interaction. Significance: Insight into how cells control cholesterol.