This peptide was further developed to detect intracellular ABL1 kinase activity in live intact cells (Placzek et al., 2010; Tang et al., 2012; Yang et al., 2013), and was applied to the investigation of the activity of the chimeric BCR-ABL1 in whole cell lysates of patients affected by CML (Yang et al., 2013). Here, BCR is linked to chronic myelogenous leukemia, BCR-ABL1 positive.