title: LGR4/GPR48 inactivation leads to aniridia-genitourinary anomalies-mental retardation syndrome defects.
abstract: AGR syndrome (the clinical triad of aniridia, genitourinary anomalies, and mental retardation, a subgroup of WAGR syndrome for Wilm's tumor, aniridia, genitourinary anomalies, and mental retardation) is a rare syndrome caused by a contiguous gene deletion in the 11p13-14 region. However, the mechanisms of WAGR syndrome pathogenesis are elusive. In this study we provide evidence that LGR4 (also named GPR48), the only G-protein-coupled receptor gene in the human chromosome 11p12-11p14.4 fragment, is the key gene responsible for the diseases of AGR syndrome. Deletion of Lgr4 in mouse led to aniridia, polycystic kidney disease, genitourinary anomalies, and mental retardation, similar to the pathological defects of AGR syndrome. Furthermore, Lgr4 inactivation significantly increased cell apoptosis and decreased the expression of multiple important genes involved in the development of WAGR syndrome related organs. Specifically, deletion of Lgr4 down-regulated the expression of histone demethylases Jmjd2a and Fbxl10 through cAMP-CREB signaling pathways both in mouse embryonic fibroblast cells and in urinary and reproductive system mouse tissues. Our data suggest that Lgr4, which regulates eye, kidney, testis, ovary, and uterine organ development as well as mental development through genetic and epigenetic surveillance, is a novel candidate gene for the pathogenesis of AGR syndrome.
authors: From the Institute of Biosciences and Technology and Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, Houston, Texas 77030 and.
authors: Tingfang
authors: T
authors: Yi
authors: Jinsheng
authors: J
authors: Weng
authors: Stefan
authors: S
authors: Siwko
authors: Jian
authors: J
authors: Luo
authors: Dali
authors: D
authors: Li
authors: Mingyao
authors: M
authors: Liu
mesh_terms: D000818:Animals; D001007:Anxiety / Q000235:genetics; D002460:Cell Line; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000235:genetics; D044783:F-Box Proteins / Q000378:metabolism; D005260:Female; D017353:Gene Deletion; D005786:Gene Expression Regulation / Q000235:genetics; D056466:Histone Demethylases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases / Q000378:metabolism; D007858:Learning; D008297:Male; D051379:Mice; D009928:Organ Specificity; D043562:Receptors, G-Protein-Coupled / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics; D017624:WAGR Syndrome / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology / Q000523:psychology
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D044783:F-Box Proteins; C496200:LGR4 protein, mouse; D043562:Receptors, G-Protein-Coupled; D056466:Histone Demethylases; C560307:JMJD2A protein, mouse; D056484:Jumonji Domain-Containing Histone Demethylases; C524747:Kdm2b protein, mouse
keywords: AGR Syndrome; CREB; Fbxl10; G-protein-coupled Receptors (GPCR); Histone Demethylase; Histone Methylation; Jmjd2a; Kidney; LGR4; Ovary