Genitourinary (GU) birth defects are among the most common yet least studied congenital malformations. Congenital anomalies of the kidney and urinary tract (CAKUTs) have high morbidity and mortality rates and account for ∼30% of structural birth defects. Copy number variation (CNV) mapping revealed that 16p11.2 is a hotspot for GU development. The only gene covered collectively by all of the mapped GU-patient CNVs was MYC-associated zinc finger transcription factor (), and CNV frequency is enriched in nonsyndromic GU-abnormal patients. Knockdown of in HEK293 cells results in differential expression of several WNT morphogens required for normal GU development, including Wnt11 and Wnt4. knockdown also prevents efficient transition into S phase, affects transcription of cell-cycle regulators, and abrogates growth of human embryonic kidney cells. Murine is ubiquitously expressed, and a CRISPR-Cas9 mouse model of deletion results in perinatal lethality with survival rates dependent on copy number. Homozygous loss of results in high penetrance of CAKUTs, and is haploinsufficient for normal bladder development. , once thought to be a simple housekeeping gene, encodes a dosage-sensitive transcription factor that regulates urogenital development and contributes to both nonsyndromic congenital malformations of the GU tract as well as the 16p11.2 phenotype.

The spectrum of congenital anomalies affecting either the upper tract (kidneys and ureters) or lower tract (reproductive organs) of the genitourinary (GU) system are fundamentally linked by the developmental origin of multiple GU tissues, including the kidneys, gonads, and reproductive ductal systems: the intermediate mesoderm. Although ∼31% of DiGeorge/del22q11.2 syndrome patients exhibit GU defects, little focus has been placed on the molecular etiology of GU defects in this syndrome. Among del22q11.2 patients exhibiting GU anomalies, we have mapped the smallest relevant region to only five genes, including encodes a src-homology adaptor protein implicated in mediating tyrosine kinase signaling, and is expressed in the developing GU-tract in mice and humans. Here we show that mutant embryos exhibit gene dosage-dependent growth restriction, and homozygous mutants exhibit upper GU defects at a microdissection-detectable rate of 23%. RNA-sequencing revealed that 52 genes are differentially regulated in response to uncoupling from its signaling pathways in the developing kidney, including a fivefold up-regulation of, a known regulator of nephron progenitor differentiation. Additionally, heterozygous adult males exhibit cryptorchidism, lower testis weight, lower sperm count, and subfertility. Together, these data indicate that is intimately involved in normal development of both the upper and lower GU tracts, and disruption of contributes to the high incidence of GU defects associated with deletion at 22q11.2.

Failure of embryo implantation accounts for a significant percentage of female infertility. Exquisitely coordinated molecular programs govern the interaction between the competent blastocyst and the receptive uterus. Decidualization, the rapid proliferation and differentiation of endometrial stromal cells into decidual cells, is required for implantation. Decidualization defects can cause poor placentation, intrauterine growth restriction, and early parturition leading to preterm birth. Decidualization has not yet been systematically studied at the genetic level due to the lack of a suitable high-throughput screening tool. Herein we describe the generation of an immortalized human endometrial stromal cell line that uses yellow fluorescent protein under the control of the prolactin promoter as a quantifiable visual readout of the decidualization response (hESC-PRLY cells). Using this cell line, we performed a genome-wide siRNA library screen, as well as a screen of 910 small molecules, to identify more than 4,000 previously unrecognized genetic and chemical modulators of decidualization. Ontology analysis revealed several groups of decidualization modulators, including many previously unappreciated transcription factors, sensory receptors, growth factors, and kinases. Expression studies of hits revealed that the majority of decidualization modulators are acutely sensitive to ovarian hormone exposure. Gradient treatment of exogenous factors was used to identify EC50 values of small-molecule hits, as well as verify several growth factor hits identified by the siRNA screen. The high-throughput decidualization reporter cell line and the findings described herein will aid in the development of patient-specific treatments for decidualization-based recurrent pregnancy loss, subfertility, and infertility.

Retinoic Acid (RA) signaling has long been speculated to regulate embryo implantation, because many enzymes and proteins responsible for maintaining RA homeostasis and transducing RA signals are tightly regulated in the endometrium during this critical period. However, due to lack of genetic data, it was unclear whether RA signaling is truly required for implantation, and which specific RA signaling cascades are at play. Herein we utilize a genetic murine model that expresses a dominant negative form of RA receptor specifically in female reproductive organs to show that functional RA signaling is fundamental to female fertility, particularly implantation and decidualization. Reduction in RA signaling activity severely affects the ability of the uterus to achieve receptive status and decidualize, partially through dampening follistatin expression and downstream activin B/BMP2 signaling. To confirm translational relevance of these findings to humans, human endometrial stromal cells (hESCs) were treated with a pan-RAR antagonist to show that in vitro decidualization is impaired. RNAi perturbation of individual RAR transcripts in hESCs revealed that RARα in particular is essential for proper decidualization. These data provide direct functional evidence that uterine RAR-mediated RA signaling is crucial for mammalian embryo implantation, and its disruption leads to failure of uterine receptivity and decidualization resulting in severely compromised fertility.Significance Statement: Female infertility affects as many as million individuals worldwide, with 10% of cases remaining unsolved after clinical investigation. Retinoic acid is the biologically functional metabolite of dietary vitamin A. The current study shows that in the event that the mammalian uterus cannot respond properly to retinoic acid, it cannot properly receive an otherwise healthy embryo for implantation, and pregnancy is unlikely to be achieved. A functional uterine response to retinoic acid is therefore critical for early pregnancy success.

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