Quantative analysis of urinary osteopontin phosphorylation level in healthy volunteers

摘要

Phosphate groups in OPN were distributed over 20 potential phosphorylation sites. Data from the peptide phosphorylation analysis are summarized in the resulting map of PTM sonthe figure above, which also contains a comparison with the PTM sofhuman OPN, determined recently by B. Christensen group (1, 2). The observed degree of phosphorylationon urinary OPN is significantly lower than the levels observedin milk OPN (2), showing tissue-specific phosphorylation.