title: Sex-specific roles of beta-catenin in mouse gonadal development.
abstract: Sexually dimorphic development of the gonads is controlled by positive and negative regulators produced by somatic cells. Many Wnt ligands, including ones that signal via the canonical beta-catenin pathway, are expressed in fetal gonads. beta-catenin, a key transcriptional regulator of the canonical Wnt pathway and an element of the cell adhesion complex, is essential for various aspects of embryogenesis. To study the involvement of beta-catenin in sex determination, we ablated beta-catenin specifically in the SF1-positive population of somatic cells. Although beta-catenin was present in gonads of both sexes, it was necessary only for ovarian differentiation but dispensable for testis development. Loss of beta-catenin in fetal testes did not affect Sertoli cell differentiation, testis morphogenesis or masculinization of the embryos. However, we observed molecular and morphological defects in ovaries lacking beta-catenin, including formation of testis-specific coelomic vessel, appearance of androgen-producing adrenal-like cells and loss of female germ cells. These phenotypes were strikingly similar to those found in the R-spondin1 (Rspo1) and Wnt4 knockout ovaries. In the absence of beta-catenin, expression of Wnt4 was down-regulated while that of Rspo1 was not affected, placing beta-catenin as a component in between Rspo1 and Wnt4. Our results demonstrate that beta-catenin is responsible for transducing sex-specific signals in the SF1-positive somatic cell population during mouse gonadal development.
authors.affiliation: Department of Veterinary Biosciences, University of Illinois at Urbana-Champaign, 3806 VMBSB, 2001 South Lincoln Avenue, Urbana, IL 61802, USA.
authors.forename: Chia-Feng
authors.initials: CF
authors.lastname: Liu
authors.forename: Nathan
authors.initials: N
authors.lastname: Bingham
authors.forename: Keith
authors.initials: K
authors.lastname: Parker
authors.forename: Humphrey H-C
authors.initials: HH
authors.lastname: Yao
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006066:Gonads / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D000072260:RNA Splicing Factors; D012733:Sex Differentiation; D015398:Signal Transduction; D013045:Species Specificity; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D000072260:RNA Splicing Factors; C491514:Sf1 protein, mouse; D014157:Transcription Factors; D051176:beta Catenin