Duan et al., 1999 - Insulin-like growth factor binding protein 2 is a growth inhibitory protein conserved in zebrafish. Proceedings of the National Academy of Sciences of the United States of America   96(26):15274-15279 Full text @ Proc. Natl. Acad. Sci. USA

Fig. 3 The zebrafish IGFBP-2 cDNA encodes a protein that binds to IGFs but not to insulin and Des(1-3)IGF-I. (A) Ligand blot analysis of CM prepared from the pRc/CMV-IGFBP-2-transfected clones 2, 5, and 6 (lanes 2-4), the pRC/CMV vector-transfected clones 1 and 2 (lanes 5 and 6), and pure bovine IGFBP-2 (lane 1). (B) Affinity crosslinking of [125I] IGF-I to zebrafish IGFBP-2 produced by CHO cells (IGFBP-2-transfected clone 2). Binding was competed by the addition of no competitor (lane 2), 500 ng of IGF-I (lane 3), IGF-II (lane 4), Des(1-3)IGF-I (lane 5), and insulin (lane 6). Lane 1 is the negative control that did not have any zebrafish IGFBP-2. The competition of [125I] IGF-I was similar in all other IGFBP-2-transfected clones examined (clones 5 and 6). (C) Affinity crosslinking of [125I] IGF-II to zebrafish IGFBP-2 produced by CHO cells (IGFBP-2-transfected clone 2). Binding was competed by the addition of no competitor (lane 2), 500 ng of IGF-I (lane 3), IGF-II (lane 4), Des(1-3)IGF-I (lane 5), and insulin (lane 6). Lane 1 is the negative control that did not have any zebrafish IGFBP-2. The competition of [125I] human IGF-II was similar in other IGFBP-2-transfected clones examined (clones 5 and 6).

Fig. 4 The expression of IGFBP-2 gene is increased by fasting and decreased by GH treatment in zebrafish. (A) Tissue distribution pattern of IGFBP-2 mRNA. Northern blot analysis of RNA samples isolated from 20-hr embryos (lane 1), whole body of adult zebrafish (lane 2), and brain (lane 3), eye (lane 4), ovary (lane 5), liver (lane 6), intestine (lane 7), muscle (lane 8) and fin (lane 9) collected from adult fish. (B) Effect of fasting on IGFBP-2 mRNA expression. RNA was isolated from fed (control) or fasted adult zebrafish. The values are means ± SE of three animals. *, P < 0.05 compared with the control. (C) Effect of GH on IGFBP-2 mRNA expression. Adult zebrafish were injected with pure seabass GH (1 μg/ml) or saline and sacrificed 15, 24, or 48 hr after the injection. The values are means ± SE of three animals. *, P < 0.05 compared with the control.

Acknowledgments:
ZFIN wishes to thank the journal Proceedings of the National Academy of Sciences of the United States of America for permission to reproduce figures from this article. Please note that this material may be protected by copyright. Full text @ Proc. Natl. Acad. Sci. USA