Methylation of the RGG repeats disrupts ribosome association of Sbp1. (A) Distribution of His-tagged Sbp1 proteins in the polysome profile of 5′UTRPab1-FLuc-poly(A). (B) Distribution of His-tagged methylated Sbp1m proteins in the polysome profile of 5′UTRPab1-FLuc-poly(A). Capped 5′UTRPab1 with luciferase reporter, 5′UTRPab1-FLuc-poly(A), was incubated with ΔSbp1 cell extract in the presence of either 3 µM Sbp1 (A) or Sbp1m (B). 10%–15% sucrose gradient was used for polysome profiling, and distribution of the protein was monitored by western blot. Peaks of polysome, 80S, 60S, 40S, and mRNA are indicated.