Stable transgenic seeds expressing SnRK2.6 as an N-terminally tagged YFP fusion in two genetic backgrounds, NIL-DOG1 and dog1-1, were used as the starting biological material. The target protein was purified through immunoprecipitation from native dry seed crude extracts of both genotypes in three independent biological replicates. Samples were split and measured using both DDA and PRM-based methods. This assay aimed to investigate the influence of the dog1-1 mutation on the phosphorylation status of SnRK2.6 activation loops.