Figure 1.

MxA forms variably sized and shaped mesoscale structures in the cytoplasm distinct from the endoplasmic reticulum (ER). Cultures of human HEK293T cells grown in 35 mm plates were transiently transfected the pHA-MxA expression vector (obtained from Stertz et al. 2006), fixed 1–2 days later, permeabilized using a digitonin-containing buffer, and the distribution of MxA and the ER structural protein reticulon-4 (RTN4) evaluated using immunofluorescence methods (imaged using an 100x oil immersion objective and z-stack data collection). Panel A, MxA structures in transiently transfected HEK293T cells (Scale bar = 10 µm). Arrows point to large compact mesoscale MxA-positive structures as observed in 25–35% of transfected cells. Panel B, MxA granular structures were distinct from the RTN4-positive ER. Scale bar = 5 µm.

Adapted from Yuan and Sehgal (2016) and Davis et al. (2019).