Leak-free Lamina

Your urinary system is built to be leak-free. Your ureter – the tube that carries urine from your kidneys to your bladder – is made watertight by two layers of tissue: the uroepithelium and a connective tissue layer called the lamina propria. Using mice, researchers investigate how the lamina propria forms. Looking at the ureter as it developed in mice from embryos (pictured, top) to newborns (bottom), they fluorescently tagged the uroepithelium (red) and smooth muscle (green), which sandwiched the lamina propria. They found lamina propria and smooth muscle cells develop from the same cells in response to chemical signals called SHH and WNT. What finally tells these cells to follow different fates? ... whether a third chemical signal, BMP4, is around or not. With BMP4, they become smooth muscle and without it, lamina propria.

Image created using Leica Microsystems microscopy

Written by Lux Fatimathas

Lux Fatimathas

Writer

Having pursued science through a career in research, communications and publishing, she is currently a writer and editor for a healthcare marketing agency and also juggles freelance science writing.

• Image from work by Philipp Straube, Anja Beckers and Ulrich W. H. Jany, and colleagues
• Institute of Molecular Biology, Hannover Medical School, Hannover, Germany
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
• Published in Disease Models & Mechanisms, February 2025