Fig. 1. GA-independent interactions between distinct viral proteins and SLR1.

a Schematic diagrams of SLR1 and its deletion mutants and their interaction with distinct viral proteins (SRBSDV SP8, RBSDV P8, RSV P2 and RSMV M). The right panel shows that the conserved GRAS domain of SLR1 is required for interactions. In the Y2H system, viral proteins were fused with BD while SLR1 and its mutant derivatives were fused with AD yeast vectors. The different combinations of constructs transformed into yeast cells were grown on SD-L-T-H-Ade plates at 30 °C and photos were taken after 3 days. b BiFC assays confirming the interactions of SLR1 with viral proteins SP8 and RSV P2. SLR1-cYFP was agro-injected together with SP8-nYFP, P2-nYFP or Gus-nYFP into Nicotiana benthamiana leaves, and the samples were imaged by confocal microscopy at 48 hpi. Scale bar = 50 µm. Each experiment was repeated three times with similar results. Co-IP assay showing that SLR1 interacted with viral proteins SP8 (c), P2 (d) and M (e) in vivo. Total proteins were extracted from N. benthamiana leaves co-expressing SLR1-flag with SP8-myc, RSV P2-myc or RSMV M-flag, then precipitated with FLAG beads and probed with anti-flag and anti-myc antibodies for immunoblot analysis. The samples with GFP-flag served as negative control. Red asterisks indicate the specific band. Each experiment was repeated three times with similar results. Source data including uncropped scans of gels (c–e) are provided in the Source data file.