Abstract
β-catenin is a key signalling molecule in the canonical Wnt pathway, which plays a role in cell adhesion, embryogenesis and sex determination. However, little is known about its function in teleosts. We cloned and characterized the full-length β-catenin1 gene from half-smooth tongue sole (Cynoglossus semilaevis), which was designated CS-β-catenin1. The CS-β-catenin1 cDNA consists of 2,346 nucleotides and encodes a protein with 782 amino acids. Although CS-β-catenin1 was transcribed in the gonads of both sexes, the level was significantly higher in ovaries compared to testes. Furthermore, the mRNA level of CS-β-catenin1 was significantly upregulated at 160 days and constantly increased until 2 years of age. In situ hybridization revealed that CS-β-catenin1 mRNA was mainly localized in oocyte cells, especially in stage I, II and III oocytes. When CS-β-catenin1 expression was inhibited by injection of quercetin in the ovaries, levels of CS-Figla and CS-foxl2 mRNA were significantly down-regulated, and CS-dmrt1 was up-regulated, which suggested that CS-β-catenin1 is a potential upstream gene of CS-Figla and is involved in the development of the ovaries, i.e., folliculogenesis.
Highlights
As the key molecule of cellular junctions, as well as the pivotal element of the canonical Wnt signalling pathway [1,2], β-catenin plays critical roles in cell growth and development, disease pathogenesis and cell adhesion [3,4]
Through the BLASTx program, the CS-β-catenin1 protein showed a high degree of identity to other fish, including Larimichthys crocea (99%), Carassius auratus (96%), and Pelodiscus sinensis (96%)
We identified a homologous gene of Wnt4 (Wnt4a) and found that it was predominately expressed in oocytes in the ovaries, and in male germ cells, it was mainly expressed in the testes [43]
Summary
As the key molecule of cellular junctions, as well as the pivotal element of the canonical Wnt signalling pathway [1,2], β-catenin plays critical roles in cell growth and development, disease pathogenesis and cell adhesion [3,4]. Several studies have found that β-catenin has a significant link to mammalian sex determination and differentiation. Β-catenin is transcribed in the testis and ovaries [5,6,7], which suggests that it has a dual role in the gonad development of both sexes. The disruption of β-catenin in mouse ovaries causes severe deficiencies in gonad development, affecting the occurrence of masculinization, formation of testis-specific coelomic vessels and even the loss of female germ cells [7].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
