Small Nuclear RING Finger Protein Expression during Gonad Development: Regulation by Gonadotropins and Estrogen in the Postnatal Ovary

Abstract

Small nuclear RING finger protein (SNURF/RNF4) is a steroid receptor coregulator that is down-regulated in testicular germ cell cancer. In this work, we examined SNURF expression during murine fetal gonad development and postnatal ovarian folliculogenesis by in situ hybridization and immunohistochemical staining. SNURF mRNA was detectable in gonads of both sexes from embryonic 10.5 days post conception onward. SNURF protein localized to gonocytes and somatic Leydig and Sertoli cells of fetal testis and in oogonia and supporting cells of fetal ovary. In murine postnatal ovary, SNURF mRNA and protein were expressed throughout folliculogenesis, peaking in the oocytes of preantral follicles. Lower amounts of SNURF mRNA and protein were also present in granulosa cells of secondary, antral, and preovulatory follicles and in luteal glands. Exposure of immature female mice and rats to gonadotropin from pregnant mare serum and human chorionic gonadotropin did not change dramatically SNURF mRNA levels in ovary. SNURF mRNA expression was increased in ovaries of immature mice treated with diethylstilbestrol, an effect that was blocked by the pure antiestrogen ICI 182,780. SNURF protein was constitutively expressed in oocytes of hypophysectomized rats, and its content was augmented by estradiol in granulosa cells. In granulosa cell culture, SNURF mRNA accumulation was transiently increased by treatment with the LH agonists phorbol myristate and forskolin at 4 h after treatment and at 48 h in differentiated cells expressing markers of the preovulatory phenotype. These results suggest a role for SNURF in fetal germ cell development as well as in oocyte and granulosa cell maturation in an estrogen- and gonadotropin-regulated fashion.

Expression of Eleven Egg Performance-associated Genes in the Ovary of Zi Geese <i>Anser anser domestica</i>

“…Ring finger proteins could play an important role in energy metabolism, protein synthesis, oocyte maturation, tumorigenesis (Fang et al, 2003;Hirvonen-Santti et al, 2004;Koyama et al, 2008). In present study, the relative expression level of RNF 130 in the ovaries of laying geese increased by 4.64 ±0.29 fold compared with those of pre-laying geese.…”

An integrated approach of immunogenomics and bioinformatics to identify new Tumor Associated Antigens (TAA) for mammary cancer immunological prevention

“…It is expressed at very high levels in testis and at much lower levels in several other tissues. When ectopically expressed, it inhibits the proliferation of both somatic and germ cell tumor-derived cells [32,33]. Cradd encodes a death domain (CARD/DD)-containing protein and induces apoptosis [34,35].…”

Cross Talk in Hormonally Regulated Gene Transcription through Induction of Estrogen Receptor Ubiquitylation

“…The proposed mechanism for this enhancement was through repressing suppression by androgen receptor which inhibits transcription of this gene through interactions with Sf-1 (23). However, SNURF, which also serves as a coactivator for ER␣, accepts ubiquitin from ubc4 and is up-regulated by estrogen exposure (18,22,51). It is plausible, therefore, that the effects of SNURF on LH␤ gene transcription are in fact through ER␣ ubiquitylation whose increased association with the preinitiation complex, and specifically Pitx1, facilitates competition of the latter with androgen receptor for binding to the putative ligand binding domain of Sf-1 (see reference 59).…”