WNT signalling plays a central role in mammalian sex determination by promoting ovarian development and repressing aspects of testis development in the early gonad. Dickkopf homolog 1 (DKK1) is a WNT signalling antagonist that plays critical roles in multiple developmental systems by modulating WNT activity. Here, we examined the role of DKK1 in mouse sex determination and early gonadal develop...

Lawsonia intracellularis is an obligate intracellular bacterial pathogen that causes proliferative enteropathy (PE) in pigs. L. intracellularis infection causes extensive intestinal crypt cell proliferation and inhibits secretory and absorptive cell differentiation. However, the affected host upstream cellular pathways leading to PE are still unknown. β-catenin/Wnt signalling is essential in ma...

Two lipids (palmitate and palmitoleic acid) are appended onto Wnt proteins. It has been suggested that palmitate is required for signalling, whereas palmitoleic acid is necessary for progression through the secretory pathway. By mutating the relevant amino acids, we have investigated how these adducts contribute to the secretion and signalling activity of Wingless, the main Drosophila member of...

Fibrosis in animal models and human diseases is associated with aberrant activation of the Wnt/β-catenin pathway. Despite extensive research efforts, effective therapies are still not available. Myofibroblasts are major effectors, responsible for extracellular matrix deposition. Inhibiting the proliferation of the myofibroblast is crucial for treatment of fibrosis. Proliferation of myofibroblas...

BACKGROUND The zebrafish has the capacity to regenerate many tissues and organs. The caudal fin is one of the most convenient tissues to approach experimentally due to its accessibility, simple structure and fast regeneration. In this work we investigate how the regenerative capacity is affected by recurrent fin amputations and by experimental manipulations that block regeneration. METHODOLOG...

Phosphatidylinositol (PI) 4-phosphate (PI(4)P) and its metabolizing enzymes serve important functions in cell signalling and membrane traffic. PI 4-kinase type IIα (PI4KIIα) regulates Wnt signalling, endosomal sorting of signalling receptors, and promotes adaptor protein recruitment to endosomes and the trans-Golgi network. Here we identify the E3 ubiquitin ligase Itch as binding partner and re...

Mouse F9 cells differentiate into primitive extraembryonic endoderm (PrE) with retinoic acid (RA) treatment, as the result of an up-regulation of Gata6, which when translated directly activates Wnt6. Canonical Wnt signalling is required for PrE differentiation, and this, like most developmental processes, requires input from one or more additional pathways, including hedgehog (Hh). The Hh pathw...

The role of Wnt signalling in the serrated neoplastic pathway of colorectal tumourigenesis appears to be heterogeneous. Wnt pathway abnormalities contribute to the progression of at least a subset of traditional serrated adenomas of the colorectum, but may play a less active role in its pathogenesis compared with that in conventional adenoma-carcinoma. However, immunohistochemical studies of β-...