title: Role of β-catenin in post-meiotic male germ cell differentiation.
abstract: Though roles of β-catenin signaling during testis development have been well established, relatively little is known about its role in postnatal testicular physiology. Even less is known about its role in post-meiotic germ cell development and differentiation. Here, we report that β-catenin is highly expressed in post-meiotic germ cells and plays an important role during spermiogenesis in mice. Spermatid-specific deletion of β-catenin resulted in significantly reduced sperm count, increased germ cell apoptosis and impaired fertility. In addition, ultrastructural studies show that the loss of β-catenin in post-meiotic germ cells led to acrosomal defects, anomalous release of immature spermatids and disruption of adherens junctions between Sertoli cells and elongating spermatids (apical ectoplasmic specialization; ES). These defects are likely due to altered expression of several genes reportedly involved in Sertoli cell-germ cell adhesion and germ cell differentiation, as revealed by gene expression analysis. Taken together, our results suggest that β-catenin is an important molecular link that integrates Sertoli cell-germ cell adhesion with the signaling events essential for post-meiotic germ cell development and maturation. Since β-catenin is also highly expressed in the Sertoli cells, we propose that binding of germ cell β-catenin complex to β-catenin complex on Sertoli cell at the apical ES surface triggers a signaling cascade that regulates post-meiotic germ cell differentiation.
authors: Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America.
authors: Yao-Fu
authors: YF
authors: Chang
authors: Jennifer S
authors: JS
authors: Lee-Chang
authors: Krystle Y
authors: KY
authors: Harris
authors: Amiya P
authors: AP
authors: Sinha-Hikim
authors: Manjeet K
authors: MK
authors: Rao
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology*; D016764:Cell Polarity / Q000235:genetics / Q000502:physiology; D005260:Female; D020869:Gene Expression Profiling; D007150:Immunohistochemistry; D008297:Male; D008540:Meiosis / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008854:Microscopy, Electron; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012708:Sertoli Cells / Q000166:cytology / Q000378:metabolism; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D013997:Time Factors; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D051176:beta Catenin