Identification of novel fibronectin fragments detected specifically in juvenile urine

摘要: Ugl-Y (young age-related urinary glycoprotein) is an age-specific protein that we have previously identified in urine from healthy subjects under 18 years of age. Isoelectric focusing analysis gives a set three bands, Y1, Y2 and Y3, the pH region around 3. To determine complete structure Ugl-Y, purified Y1 pediatric were enzymatically cleaved, resulting peptides analyzed by sequencing and/or MALDI-TOF MS. As result, it was demonstrated consists 189 amino acid residues, identical to A723 R911 fibronectin, whereas 181 R903. Electrophoretic lysate prepared COS-7 cells transfected with Y1- or Y2-expressing vectors gave specific bands corresponding Y2, respectively, showing validity sequences determined. Partial purification serum followed western blotting revealed derived plasma. Furthermore, generated in vitro digestion fibronectin protease extracts osteoclast cells. These findings suggest probably produced degradation comprising bone matrix during process vigorous resorption children adolescents. This first report on identification characterization juvenile-specific fragments excreted into urine.