We reasoned that if the block in DENV infection under EMC4 KD is due to a decreased level of endosome-localized PS, supplementing EMC4 KD cells with purified PS in the media–which should spontaneously insert into the plasma membrane, undergo endocytosis to reach the endosome, and bypass the EMC4-dependent ER-to-endosome route–might restore virus infection. The gene discussed is EMC4; the disease is viral infectious disease.