1. Full-length AdIGFBP-5 and T47D cell-derived IGFBP-5 analyzed by mass spectrometry.a, intact AdIGFBP-5 was analyzed by ESI-MS.
Full-length AdIGFBP-5 and T47D cell-derived IGFBP-5 analyzed by mass spectrometry.a, intact AdIGFBP-5 was analyzed by ESI-MS. Multiply charged ions were converted to the molecular masses (see “Experimental Procedures”). All molecular masses are shown relative to the 28,556 Da signal, assumed to be IGFBP-5 with eight to nine disulfide bonds retained. The identity and amount of the post-translational modifications are shown in Table II. b, AdIGFBP-5 was treated with Antarctic phosphatase (AP) before being analyzed by ESI-MS. Comparison of a with b allowed phosphorylated forms of the protein to be clearly identified. c, intact human IGFBP-5 from T47D cells was analyzed by ESI-MS to reveal a pattern of modification similar to that of AdIGFBP-5 in a. A pool of full-length T47D IGFBP-5, which was 113 Da less, is marked (−113).
Mark E. Graham et al. Mol Cell Proteomics 2007;6:
© 2007 The American Society for Biochemistry and Molecular Biology