A) Expression of Arf6-Q67L in cells induces the formation of distinctive vacuoles. The left image shows a HeLa cell expressing Arf6-Q67L-GFP, which causes accumulation of large vacuolar structures. The right image shows a COS-7 cell co-expressing Arf6 Q67L (not shown) and the carboxyl terminal sequence of H-Ras fused to GFP. The H-Ras-tail-GFP highlights the Q67L vacuole clearly. B) Expression of Arf6 and EFA6 in cells promotes a phenotype similar to Arf6 Q67L.
Arf6 wild type localizes on tubular endosomes and at the PM in HeLa cells. Its GEF, EFA6, is localized mostly at the PM and causes cell ruffling. Co-expression of Arf6 and EFA6 induces the formation of vacuoles similar to expression of Arf6 Q67L.