Spatial transcriptome of the mouse cloaca. Mus musculus

Evolutionary and functional significance of the mammalian urinary bladder remains undervalued and ill-defined. Here, to determine the molecular architecture of the mouse cloaca, we collected mouse E11.5 embryo and profiled the spatial transcriptome using Geo-seq. Spatial transcriptomics reveal that Wnt2 is expressed in the triangular cloacal mesenchyme domain flanked by the umbilical arteries. Wnt2 is downregulated in Shh mutants, and knockout of Wnt2 causes reduced bladder size and single umbilical artery phenotypes. These findings collectively suggest that the Shh-Wnt2 pathway orchestrates co-development of the bladder and umbilical arteries.