Probing protein phosphatase substrate binding: Affinity pull-down of ILKAP phosphatase 2C with phosphopeptides Kim B. Højlys-Larsen *a , Kasper K. Sørensen a b , Knud J. Jensen *b and Steen Gammeltoft a Received (in XXX, XXX) Xth XXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX DOI: 10.1039/b000000x Supplementary Information Content: Fig S1: Comparison of pull-down performed at 4ºC and 30 ºC. Table S1: Mass spectrometric characterization of phosphopeptides 1-28. Table S2: Summary of ILKAP pull-down specificity for dephosphorylation targets Table S3-S7: Western Blot quantification data [a] Dr. K. B. Højlys-Larsen, Dr. K. K. Sørensen, Prof. S. Gammeltoft Department of Clinical Biochemistry Glostrup Hospital Ndr. Ringvej, 2600 Glostrup, (Denmark) Fax: (+45) 38 63 39 58 E-mail: kimlar01@regionh.dk [b] Dr. K. K. Sørensen, Prof. K. J. Jensen Faculty of Science, University of Copenhagen 40 Thorvaldsensvej, 1871 Frederiksberg (Denmark) E-mail:kjj@life.ku.dk Electronic Supplementary Material (ESI) for Molecular BioSystems This journal is © The Royal Society of Chemistry 2012