Insulin-like growth factor I activity is stored in the yolk of the avian egg.
Growth factors of maternal origin may be incorporated into the vertebrate egg and play a role in early phases of embryo growth and differentiation. An avian insulin-like growth factor I (IGF-I) activity from unfertilized chicken egg-yolk has been partially purified by HPLC. The material is slightly more hydrophobic than recombinant human IGF-I. It reacts in a human IGF-I radioimmunoassay and is specifically depleted by anti-human IGF-I antibodies. Like authentic IGF-I, the extracts enriched in IGF-I activity stimulated the accumulation of delta-crystallin mRNA in epithelial cells from chick embryo lens with a potency approximately equivalent to its IGF-I immunoactivity.
Receptors and Hormone Action Section, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892.
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Scavo
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Alemany
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Roth
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de Pablo
D000818:Animals; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D003459:Crystallins / Q000235:genetics; D004530:Egg Yolk / Q000032:analysis*; D005786:Gene Expression Regulation / Q000187:drug effects; D007334:Insulin-Like Growth Factor I / Q000032:analysis* / Q000276:immunology / Q000494:pharmacology; D007908:Lens, Crystalline / Q000196:embryology; D011863:Radioimmunoassay; D013002:Somatomedins / Q000032:analysis*
D003459:Crystallins; D013002:Somatomedins; D007334:Insulin-Like Growth Factor I