RAB28 and polycystic kidney disease 2: We found that control and rab-28(tm2636) males release similar numbers of PKD-2::GFP-labeled EVs, ruling out a function for RAB-28 in environmental EV release of PKD-2 and suggesting a possible defect whereby EV shedding into the sensory organ lumen is abnormally upregulated (Figure 4E).