homeostasis. How zonation is induced and maintained and how renewal of the adrenal
cortex is ensured remain a mystery. Here we show that capsular RSPO3 signals to the
underlying steroidogenic compartment to induce β-catenin signaling and imprint
glomerulosa cell fate. Deletion of RSPO3 leads to loss of SHH signaling and impaired organ
growth. Importantly, Rspo3 function remains essential in adult life to ensure replenishment of …