Fig. 3. S1126 phosphorylation is not required to maintain cyclin B1 binding. (A) Anti-Myc immunoprecipitates treated with phosphatase, then washed with low-salt or high-salt buffers. Notice that, despite being dephosphorylated on S1126, separase still binds cyclin B1. (B) Anti-Myc immunoprecipitates showing that, despite being phosphorylated, the LAG and 12 mutants do not bind cyclin B1.