The ADP-ribosylation factor 6 (ARF6) GTPase has a dual function in cells, regulating membrane traffic and organizing cortical actin. ARF6 activation is required for recycling of the endosomal membrane back to the plasma membrane (PM) and also for ruffling at the PM induced by Rac. Additionally, ARF6 at the PM induces the formation of actin-containing protrusions. To identify sequences in ARF6 that are necessary for these distinct functions, we examined the behavior of a chimeric protein of ARF1 and ARF6. The 1-6 chimera (with the amino half of ARF1 and the carboxyl half of ARF6) localized like ARF6 in HeLa cells and moved between the endosome and PM, but it did not form protrusions, an ARF6 effector function. Two residues in the amino-terminal half of ARF6, Q37 and S38, when substituted into the 1-6 chimera allowed protrusion formation, whereas removal of these residues from ARF6 resulted in an inability to form protrusions. Interestingly, expression of 1-6 in cells selectively inhibited protrusions induced by wild-type ARF6 but had no effect on ARF6-regulated membrane movement or Rac-induced ruffling. Thus, we have uncoupled two functions of ARF6, one involved in membrane trafficking, which is necessary for Rac ruffling, and another involved in protrusion formation.

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W e are colleagues and friends working together in busy emergency departments (EDs) in Washington, DC. As black physicians working in urban America, we do not find the recent deluge of news reports chronicling the disproportionate effect that the coronavirus disease (COVID-19) pandemic is having on the disenfranchised and minority populations in our country shocking. We have long been witness to and are in a constant state of alarm over the legal, medical, educational, social, and economic inequities faced by the most vulnerable residents of this country. 1 As this epidemic is showing all of us, the disease may vary, the particular population might be different, the name of the city or town can change, but the outcome is almost uniformly predictable. COVID-19 has highlighted racial and ethnic inequities. 2,3 We can all see them in the daily, undeniable numbers that flash at us from our phones and television screens. We are grateful to the press for illustrating the statistics with poignant, often personal stories that highlight the acuity and indecency of these inequalities. 2 Like all emergency physicians, we not only worry about the patients we treat on a daily basis with COVID-19, but we also worry about our families at home. Yet further, for us this pandemic takes on a deeper meaning. Our hometowns are the cities that are facing some of the largest tolls in COVID-19 cases among people of color. When a black, Latinx, or Native American "person under investigation" for COVID-19 comes into the ED, we not only see our patient, but we also see our mother, father, aunt, and uncle. We realize that we are among the lucky ones. We have regular jobs in the medical sectors with some stability during this pandemic. We also have a place to call home, a regular means of transportation and the ability to practice effective social distancing.Many of our black and brown patients are too sick to be discharged, showing signs of severe illness upon

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