Prolactin stimulation of tyrosyl phosphorylation of Shc proteins in Nb(2) lymphoma cells, but not mammary tissues.
Prolactin (PRL) stimulates lactogenesis in mammary cells and mitogenesis in a variety of cell types including Nb(2) cells. Studies indicate that a different composite of signaling pathways is involved in the PRL stimulation of mitogenesis as compared to lactogenesis. In the present studies, PRL is shown to stimulate the tyrosyl phosphorylation of all three isoforms of Shc proteins in Nb(2) cells (mitogenesis), but not in the mammary gland. Maximal phosphorylation of the Shc proteins is expressed between 10 and 15 min after a 50-ng/ml PRL treatment. In addition, there is an increased association between the Grb2 protein and Shc proteins upon PRL stimulation. However, no increased association between JAK2 and Shc proteins was observed in either the Nb(2) cells or mammary tissues.
Yu
T X
TX
Department of Physiology, Wayne State University School of Medicine, 540 E. Canfield, Detroit, MI 48201, USA.
Rillema
J A
JA
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D000818:Animals; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D005260:Female; D015151:Immunoblotting; D008321:Mammary Glands, Animal / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D011233:Precipitin Tests; D011247:Pregnancy; D011388:Prolactin / Q000494:pharmacology*; D011506:Proteins / Q000187:drug effects* / Q000378:metabolism; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D011506:Proteins; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014443:Tyrosine; D011388:Prolactin