The kidney, like other organs, grows in constant proportion to the rest of the body. When one kidney is removed, the remaining one hypertrophies. In a comprehensive series of studies, Chen et al. show that growth during maturation is mediated by the mTORC1 signaling pathway, which is induced by EGF-like peptides, and requires PI3K, PDK, AKT, mTORC2, and activation of mTORC1 through the combined effects of TSC and RHEB as part of a multiprotein complex localized on lysosomes. However, compensatory growth is mediated by amino acids, which act on mTORC1 independently of the previous pathway, and requires a class III PI3K (VPS34) that is known to be involved in vesicle trafficking to the lysosomes.
The Editorial Board will only consider comments that are deemed relevant and of interest to readers. The Journal will not post data that have not been subjected to peer review; or a comment that is essentially a reiteration of another comment.