Background: ADAMTS16 is a mammalian metalloproteinase with unknown function. Results: Transcription of the Adamts16 gene is regulated by Wilms tumor protein Wt1, and knockdown of Adamts16 reduces branching morphogenesis in cultured embryonic kidneys. Conclusion: Adamts16 is a Wt1 target gene during murine genitourinary development. Significance: The findings provide novel insights into gene regulatory networks controlling kidney and gonad development.

Background: Polyamines and their diamine precursor putrescine are ubiquitous organic polycations involved in cell growth and proliferation. Results: The Wilms tumor suppressor, WT1, stimulates transcription of the AOC1 gene, which encodes the key enzyme for putrescine breakdown. Conclusion: WT1-dependent regulation of putrescine degradation, mediated by AOC1, has a role in kidney morphogenesis. Significance: The findings provide novel insights into transcriptional mechanisms controlling genitourinary development.

Gonad morphogenesis relies on the correct spatiotemporal expression of a number of genes that together fulfill the differentiation of the bipotential gonad into testes or ovaries. As such, the transcription factors WT1 and GATA4 are pivotal for proper gonadal development. Here we address the contributions of GATA4 and WT1 to the sex differentiation phase in testes and ovaries. We applied an ex vivo technique for cultivating gonads in hanging droplets of media that were supplemented with vivo-morpholinos to knockdown WT1 and GATA4 either alone or in combination at the same developmental stage. We show that WT1 is equally important for both, the initial establishment and the maintenance of the sex-specific gene expression signature in testes and ovaries. We further identified Foxl2 as a novel putative downstream target gene of WT1. Moreover, knockdown of WT1 reduced mRNA levels of several molecular components of the hedgehog signaling pathway in XY gonads, whereas Gata4 vivo-morpholino treatment increased transcripts of Dhh and Ptch1 in embryonic testes. The data suggest that for its proper function, WT1 relies on the correct expression of the GATA4 protein. Furthermore, GATA4 down-regulates several ovarian promoting genes in testes, such as Ctnnb1, Fst, and Bmp2, suggesting that this repression is required for maintaining the male phenotype. In conclusion, this study provides novel insights into the role of WT1 and GATA4 during the sex differentiation phase and represents an approach that can be applied to assess other proteins with as yet unknown functions during gonadal development.

miR-22 is a HIF repressor constitutively expressed in the adult kidney and up-regulated in AKI. Specific inhibition of miR-22 is efficient in vivo and profoundly affects renal gene expression in health and disease, including up-regulation of HIF. However, the net effect on rhabdomyolysis-induced AKI outcome is neutral or even negative.

PAGE 18817:Lanes 3-6 of the original Western blot image in Fig. 3C contained the same bands as lanes 3-6 of the Western blot image in Fig. 3D, and both panels failed to indicate that separate lanes from the original blots had been spliced together. The correct Western blot image for Fig. 3C is now provided, and lines have been added to indicate the area where the blot images were joined. These changes do not affect the interpretation or conclusions of this work.