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Full-Text Articles in Medicine and Health Sciences
Insulin-Like Growth Factor Ii Acts Through An Endogenous Growth Pathway Regulated By Imprinting In Early Mouse Embryos, Daniel A. Rappolee, Karin S. Sturm, Ole Behrendtsen, Gilbert A. Schultz, Roger A. Pedersen, Zena Werb
Insulin-Like Growth Factor Ii Acts Through An Endogenous Growth Pathway Regulated By Imprinting In Early Mouse Embryos, Daniel A. Rappolee, Karin S. Sturm, Ole Behrendtsen, Gilbert A. Schultz, Roger A. Pedersen, Zena Werb
Department of Obstetrics and Gynecology Research Publications
We present evidence that insulin-like growth factor II (IGF-II) mediates growth in early mouse embryos and forms a pathway in which imprinted genes influence development during preimplantation stages, mRNA and protein for IGF-II were expressed in preimplantation mouse embryos, but the related factors IGF-I and insulin were not. IGF-I and insulin receptors and the IGF-II/mannose-6-phosphate receptor were expressed. Exogenous IGF-II or IGF-I increased the cell number in cultured blastocysts, but a mutant form of IGF-II that strongly binds only the IGF-II receptor did not. Reduction of IGF-II expression by antisense IGF-II oligonucleotides decreased the rate of progression to the blastocyst …
Platelet A-Granule Fibrinogen, Albumin, And Immunoglobulin G Are Not Synthesized By Rat And Mouse Megakaryocytes, Prem Handagama, Daniel A. Rappolee, Zena Werb, Jack Levin, Dorothy F. Bainton
Platelet A-Granule Fibrinogen, Albumin, And Immunoglobulin G Are Not Synthesized By Rat And Mouse Megakaryocytes, Prem Handagama, Daniel A. Rappolee, Zena Werb, Jack Levin, Dorothy F. Bainton
Department of Obstetrics and Gynecology Research Publications
It has been assumed that endogenous synthesis by the platelet precursor cell, the bone marrow megakaryocyte, is the major source of platelet a-granule protein. To test this hypothesis, we used mRNA phenotyping to detect in megakaryocytes the presence of mRNA transcripts specific for various proteins. Our results indicate that megakaryocytes synthesize platelet factor 4, a protein relatively specific for platelets, but do not express mRNA transcripts for the fibrinogen, albumin, or IgG found in a-granules. We have previously shown that mega- karyocytes endocytose circulating proteins, including fibrino- gen, albumin, and IgG, and incorporate them into a-granules. Thus, platelets appear to …