For Co‐IP assays, the combinations of OsRLP1‐MYC/OsSOBIR1‐FLAG or GFP‐MYC/OsSOBIR1‐FLAG (as a negative control) were introduced into rice protoplasts for 12 h as previously described (Zhang et al., 2011 ). The Co‐IP assay was conducted as described previously (Zhang et al., 2020 (link)). Briefly, the native protein was extracted using IP buffer (50 mm Tris‐HCl, pH = 8.0, 1 mm MgCl2, 0.5 m sucrose, 10 mm EDTA with 10 mm DTT) (Thermo Scientific, Waltham, MA, USA, Cat. no. 87788) with the addition of 100 μm protease inhibitor cocktail (Roche, Basel, Switzerland, Cat. no. 04693132001) for 10 min at 4 °C and subsequently centrifuged at 12 000 g, 4 °C for 10 min (Wu et al., 2019 (link)). The supernatant was incubated with 10 μl Pierce™ anti‐c‐Myc magnetic beads (Thermo Scientific, Waltham, MA, USA, Cat. no. 88844) in 2 mL centrifuge tube for 1–2 h at 4 °C. Importantly, the beads were pre‐washed three times with 1 × PBS before using. The immunoprecipitates were then washed at least three times with 1 × PBS and then re‐suspended in 50 μL 2 × SDS sample buffer. Subsequently, the protein samples were boiled at 95–100 °C for 10 min and Western blots were performed.