This gene was found in a mouse DNA array analysis of transcripts expressed in mouse preovulatory follicles.
General function
Receptor
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Cellular localization
Plasma membrane
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Ovarian function
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Expression regulated by
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Ovarian localization
Oocyte, Stromal cells
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Identification of WNT/{beta}-CATENIN signaling pathway components in human cumulus cells. Wang HX et al. Signaling via the conserved WNT/beta-CATENIN pathway controls diverse developmental processes. To explore its potential role in the ovary, we investigated the expression of WNTs, frizzled (FZD) receptors, and other pathway components in human cumulus cells obtained from oocytes collected for in vitro fertilization. Proteins were detected in cultured cells using immunofluorescence microscopy. Protein-protein interactions were analyzed by means of immunoprecipitation. WNT2, FZD2, FZD3, and FZD9 were identified but WNT1, WNT4 and FZD4 were not detected. WNT2 is co-expressed with FZD2, FZD3, and FZD9. Co-immunoprecipitation using WNT2 antibody demonstrated that WNT2 interacts with both FZD3 and FZD9, but only FZD9 antibody precipitated WNT2. We also identified DVL (disheveled), AXIN, GSK-3beta (glycogen synthase kinase-3beta), and beta-CATENIN. beta-CATENIN is concentrated in the plasma membranes. DVL co-localizes with FZD9 and AXIN in the membranes, but GSK-3beta has little colocalization with AXIN and beta-CATENIN. Interestingly, beta-CATENIN is highly co-localized with FZD9 and AXIN. CDH1 (E-cadherin) was also detected in the plasma membranes and cytoplasm, co-localized with beta-CATENIN, and CDH1 antibody precipitated beta-CATENIN. The results suggest that WNT2 could act through its receptor FZD9 to regulate the beta-CATENIN pathway in cumulus cells, recruiting beta-CATENIN into plasma membranes and promoting the formation of adherens junctions involving CDH1.
Zhao Z,et al. (Genomics. 1995) reported the identification of a human homologue for the fz gene (FZD2). The FZD2 gene was isolated from a human ovarian cDNA library and mapped to 17q21.1 by fluorescent in situ hybridization (FISH) with a corresponding cosmid. The full-length cDNA of human FZD2 encodes a protein (FZD-2) of 565 amino acids that shares 56% sequence identity with Drosophila Fz. The expression of the FZD2 gene seems to be developmentally regulated, with high levels of expression in fetal kidney and lung and in adult colon and ovary.
Follicle stages
Corpus luteum
Comment
Expression of Frizzled 2 in the mouse ovary during oestrous cycle. Wang SB et al. Summary The Wnt/beta-catenin pathway is a conserved signalling pathway that regulates gene expression and controls diverse developmental processes such as cell fate specification, cell proliferation and cell differentiation. To our knowledge, the potential role of this pathway in the adult ovary has been poorly addressed. To this end, we investigated the expression pattern of Frizzled 2 in the mouse ovary during oestrous cycle by real-time Q-PCR, in situ hybridization, Western blotting and immunohistochemistry. In this study, we used uterine wet weight and H3.2 mRNA level as two markers for classification of mouse oestrous cycle. We found that both uterine wet weight and H3.2 mRNA are the highest in the proestrus and decrease from oestrus to diestrus. During oestrous cycle, Frizzled 2 mRNA and protein exhibited the highest level in the proestrus stage and rapidly reduced from oestrus to diestrus. In situ hybridization results showed that the positive signals for Frizzled 2 are highly detected in the oocyte and stroma in proestrus stage, while moderate or weak Frizzled 2 mRNAs are localized in the oocyte, granulosa cells, stroma and corpus luteum from oestrus to diestrus. The localization pattern of Frizzled 2 protein is mostly consistent with its mRNA, but stronger Frizzled 2 proteins are present in the granulosa cells and membrane of oocyte in oestrous cycle. Our data suggest that Frizzled 2 may be involved in regulating follicle growth, oocyte maturation and luteinization during oestrous cycle.