Characterization of the mitogen-regulated protein (proliferin) receptor.
Mitogen-regulated protein (MRP/PLF; also called proliferin) is a member of the PRL-GH family expressed by the placenta in mid-gestation. This report describes an MRP/PLF receptor in uterine membrane preparations from pregnant mice. Peak receptor activity occurred at 11 days of gestation with a dissociation constant of 6 x 10(-10) M and maximal binding capacity of 86 fmole MRP/PLF/mg membrane protein. PRL, PL-I, and mannose-6-phosphate did not compete for binding, and GH competed weakly only at high concentrations. Primary cells cultured from uteri taken at days 8-11 of gestation responded to MRP/PLF with increases in DNA synthesis. Uterine cells from later stages of gestation did not respond to MRP/PLF. This is the first reported evidence of a function mediated by MRP/PLF and suggests a role for this protein in maternal-fetal interactions during reproduction. Thus, it seems that MRP/PLF is a placentally derived growth factor, which stimulates proliferation in the uterus in a developmentally defined period to coordinate uterine growth with fetal development.
Nelson
J T
JT
Department of Biochemistry and Biophysics, Iowa State University, Ames 50011.
Rosenzweig
N
N
Nilsen-Hamilton
M
M
D000818:Animals; D001667:Binding, Competitive; D004247:DNA / Q000096:biosynthesis; D005260:Female; D005865:Gestational Age; D006023:Glycoproteins / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology; D036341:Intercellular Signaling Peptides and Proteins; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D051379:Mice; D011247:Pregnancy; D011388:Prolactin; D017978:Receptors, Growth Factor / Q000378:metabolism*; D014599:Uterus / Q000378:metabolism
D006023:Glycoproteins; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; C000634106:Prl2c2 protein, mouse; D017978:Receptors, Growth Factor; C091585:proliferin receptor, mouse; D011388:Prolactin; D004247:DNA