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Structure of the receptor for insulin-like growth factor II: the puzzle amplified

R A Roth1

  • 1Department of Pharmacology, Stanford University School of Medicine, CA 94305-5332.

Science (New York, N.Y.)
|March 11, 1988
PubMed

The insulin-like growth factor II (IGF-II) is a polypeptide hormone with structural homologies to insulin and insulin-like growth factor I (IGF-I). In contrast to these other hormones, the in vivo function of IGF-II is not known. Although IGF-II can stimulate a broad range of biological responses in isolated cells, these responses have usually been found to be mediated by the insulin and IGF-I receptors. Recently, the receptor for IGF-II was found to also be the receptor for mannose-6-phosphate. Since this latter receptor has been implicated in targeting of lysosomal enzymes, the question is now raised of whether the same protein can also mediate metabolic responses to IGF-II.

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