Fig. 4.

CD248 is a membrane-facilitated binding partner for the orphan protein LRRC15. (A) RDIMIS results for LRRC15 gD-GPI or (B) LRRC15 full-length rEVs in which hits above the 98% quantile and show greater than 4× screen-specific enrichment are labeled. In both cases, results are compared with PVR screen results shown in Fig 2C. (C) Binding between CD248, expressed as a recombinant protein and immobilized on a sensor, and LRRC15-Fc (500 nM) or LRRC15 full-length or gD-GPI ectodomain expressing rEVs (0.25 mg/mL). (D) Full-length or gD-GPI CD248 was transiently expressed in cells. Cells were incubated with vesicles from cells transfected with gag-NeonGreen and full-length or gD-GPI LRRC15-expressing or an empty vector control. (E) Quantification of NeonGreen signal from D displayed as mean ± SE for three independent replicates. (F) Full-length or gD-GPI LRRC15 was transiently expressed in cells. CD248, as a tetramerized recombinant ectodomain, binding to the cell surface was determined using microscopy. (Scale bar, 20 µm.)