Expression and localization of secreted frizzled-related protein-4 in the rodent ovary: evidence for selective up-regulation in luteinized granulosa cells.
Secreted frizzled-related protein-4 (sFRP-4) belongs to a family of soluble proteins that have a Frizzled-like cysteine-rich domain and function as modulators of Wnt-Frizzled (Fz) signals. As several Wnts and Fz are expressed at defined stages of follicular development in rodent ovaries, these studies were undertaken to evaluate the hormone-regulated expression and localization of sFRP-4. In the mouse ovary, the expression of sFRP-4 mRNA was up-regulated in granulosa cells of large antral follicles after human chorionic gonadotropin administration and was also elevated in corpora lutea, as determined by RT-PCR and in situ hybridization analyses. In hypophysectomized rat ovaries, sFRP-4 expression was similarly induced by human chorionic gonadotropin and further up-regulated by PRL. PRL also stimulated the secretion of sFRP-4 protein from luteinized rat granulosa cells in culture. Therefore, regulation of sFRP-4 by LH and PRL may be important for modulating Fz-1, which is known to be expressed in periovulatory follicles, and Wnt-4/Fz-4, which are expressed in corpora lutea.
Hsieh
Minnie
M
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
Mulders
Sabine M
SM
Friis
Robert R
RR
Dharmarajan
Arun
A
Richards
JoAnne S
JS
D000818:Animals; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D003338:Corpus Luteum / Q000378:metabolism / Q000502:physiology; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D006107:Granulosa Cells / Q000378:metabolism / Q000502:physiology; D007016:Hypophysectomy; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D006080:Ovarian Follicle / Q000378:metabolism; D010053:Ovary / Q000378:metabolism*; D010060:Ovulation / Q000502:physiology; D011247:Pregnancy; D011388:Prolactin / Q000494:pharmacology; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011980:Receptors, Progesterone / Q000172:deficiency; D014018:Tissue Distribution; D015854:Up-Regulation
D006063:Chorionic Gonadotropin; D006064:Gonadotropins, Equine; D011506:Proteins; D012333:RNA, Messenger; D011980:Receptors, Progesterone; D004958:Estradiol; D011388:Prolactin