Interactions of the receptor for insulin-like growth factor II with mannose-6-phosphate and antibodies to the mannose-6-phosphate receptor.
Recently, the sequence of the human receptor for insulin-like growth factor II (IGF-II) was found to be 80% identical [Morgan et al., (1987) Nature 329, 301-307] to the sequence of a partial clone of the bovine cation-independent mannose-6-phosphate receptor [Lobel et al., (1987) Proc. Natl. Acad. Sci. USA 84, 2233-2237]. In the present study, the purified receptor for insulin-like growth factor II (IGF-II) was found to react with two different polyclonal antibodies to the purified mannose-6-phosphate receptor. Moreover, mannose-6-phosphate was found to stimulate the binding of labeled IGF-II to the IGF-II receptor by two-fold. This effect had the same specificity and affinity as the reported binding of mannose-6-phosphate to its receptor; mannose-1-phosphate and mannose had no effect on the binding of labeled IGF-II to its receptor, and the half-maximally effective concentration of mannose-6-phosphate was 0.3 mM. Also, mannose-6-phosphate did not affect labeled IGF-II binding to the insulin receptor. These results support the hypothesis that a single protein of Mr-250,000 binds both IGF-II and mannose-6-phosphate. Furthermore, they indicate that mannose-6-phosphate can modulate the interaction of IGF-II to its receptor.
D002352:Carrier Proteins / Q000276:immunology* / Q000502:physiology; D003429:Cross Reactions; D006600:Hexosephosphates / Q000494:pharmacology*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D008360:Mannosephosphates / Q000494:pharmacology*; D017527:Receptor, IGF Type 2; D011972:Receptor, Insulin / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D017451:Receptors, Somatomedin; D013002:Somatomedins / Q000378:metabolism*
D002352:Carrier Proteins; D006600:Hexosephosphates; D008360:Mannosephosphates; D017527:Receptor, IGF Type 2; D017451:Receptors, Somatomedin; D013002:Somatomedins; C027693:mannose-6-phosphate; D007335:Insulin-Like Growth Factor II; D011972:Receptor, Insulin