Liver receptor homolog-1 (LRH-1) is an orphan nuclear receptor that is critical for the growth and proliferation of cancer cells and other biological processes, including lipid transportation and metabolism, sexual determination and steroidogenesis. However, because homozygous lrh-1 mice die in utero, the regulatory mechanisms involved in embryonic development mediated by this receptor are poorly understood. In the present study, we performed transcription activator-like effector nuclease (TALEN)-mediated loss-of-function assays, taking advantage of zebrafish external fertilization, to investigate the function of lrh-1. The digestive organs were affected by lrh-1 depletion as a result of cell-cycle arrest (at the checkpoint of G1 to S phase), but not cell apoptosis. Biochemical analysis revealed that LRH-1 augments the transcriptional activity of β-catenin 1 and 2 via physical interactions. Screening the specific ligand(s) sensed by LRH-1 during organogenesis revealed that phosphatidylcholine (PC), a potential ligand, is the upstream target of LRH-1 during endoderm development. These data provide evidence for the crosstalk between the PC/LRH-1 and Wnt/β-catenin signaling pathways during the expansion growth of endoderm organs.
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http://dx.doi.org/10.1016/j.jgg.2017.03.006 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, State Key Laboratory Breeding Base of Eco-Environments and Bio-Resources of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing 400715, China.
Heterozygotic mutations are responsible for various congenital diseases in the heart, pancreas, liver, and other organs in humans. However, there is lack of an animal that can comprehensively model these diseases since GATA6 is essential for early embryogenesis. Here, we report the establishment of a knockout zebrafish which recapitulates most of the symptoms in patients with mutations, including cardiac outflow tract defects, pancreatic hypoplasia/agenesis, gallbladder agenesis, and various liver diseases.
View Article and Find Full Text PDFClin Transl Med
December 2024
Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucía-University of Pablo de Olavide-University of Seville-CSIC, Seville, Spain.
Background: The complex aetiology of type 1 diabetes (T1D), characterised by a detrimental cross-talk between the immune system and insulin-producing beta cells, has hindered the development of effective disease-modifying therapies. The discovery that the pharmacological activation of LRH-1/NR5A2 can reverse hyperglycaemia in mouse models of T1D by attenuating the autoimmune attack coupled to beta cell survival/regeneration prompted us to investigate whether immune tolerisation could be translated to individuals with T1D by LRH-1/NR5A2 activation and improve islet survival.
Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from individuals with and without T1D and derived into various immune cells, including macrophages and dendritic cells.
Front Immunol
October 2024
Andalusian Center of Molecular Biology and Regenerative Medicine (CABIMER), Junta de Andalucía-University of Pablo de Olavide-University of Seville-Consejo Superior de Investigaciones Científicas (CSIC), Seville, Spain.
Cell Metab
January 2025
Translational Medicine Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, China; Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision, and Brain Health), National Key Laboratory of Macromolecular Drugs and Large-scale Preparation, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China. Electronic address:
Bile acid (BA) homeostasis is vital for various physiological processes, whereas its disruption underlies cholestasis. The farnesoid X receptor (FXR) is a master regulator of BA homeostasis via the ileal fibroblast growth factor (FGF)15/19 endocrine pathway, responding to postprandial or abnormal transintestinal BA flux. However, the de novo paracrine signal mediator of hepatic FXR, which governs the extent of BA synthesis within the liver in non-postprandial or intrahepatic cholestatic conditions, remains unknown.
View Article and Find Full Text PDFComput Struct Biotechnol J
December 2024
Vanderbilt University Medical Center, Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Nashville, TN 37232, USA.
The nuclear receptor Liver Receptor Homolog-1 (LRH-1, ) is a ligand-regulated transcription factor and validated drug target for several human diseases. LRH-1 activation is regulated by small molecule ligands, which bind to the ligand binding domain (LBD) within the full-length LRH-1. We recently identified 57 compounds that bind LRH-1, and unexpectedly found these compounds regulated either the isolated LBD, or the full-length LRH-1 in cells, with little overlap.
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