Institution: NIH Library Sign In as Member / Individual

This Article Full Text Services Alert me to new issues of the journal Request Copyright Permission

Fig. 7. HN does not prevent IGFBP-3?IGF-I binding. rhIGFBP-3 was mixed with ¹²⁵I-rhIGF-I and/or unlabeled rhIGF-I and/or HN or HNG peptide (1 or 5 m g, i.e., 10 or 50 molar excess).¹²⁵I-IGF-I migrates at 8 kDa either in the presence or absence of cross-linking reagent (DSS) (lanes 1 and 2, respectively). When cross-linked to rhIGFBP-3, it migrates at »38 kDa (lane 3); whereas competition with excess (1.5 mg) cold rhIGF-I displaces ¹²⁵I-IGF-I from IGFBP-3 (lane 4). Addition of HN at 10 or 50´excess did not block ¹²⁵I-IGF-I?IGFBP-3 binding (lanes 5 and 6, respectively). Neither did the addition of HNG (lanes 7 and 8). Unlabeled IGF-I was still able to displace ¹²⁵I-IGF-I from IGFBP-3 in the presence of 10´HN peptide (lane 9) or HNG (lane 10). Mobility of ¹²⁵I-IGF-I did not change when cross-linked to HN or to HNG indicating the lack of binding between IGF-I and HN (lanes 11 and 12, respectively). Lane 13 shows control with ¹²⁵I-IGF-I and cold IGF-I in the presence of cross-linking reagent. The results are a representative from three independent experiments.