mTORC1-mediated inhibition of polycystin-1 expression drives renal cyst formation in tuberous sclerosis complex
نویسندگان
چکیده
Previous studies report a cross-talk between the polycystic kidney disease (PKD) and tuberous sclerosis complex (TSC) genes. mTOR signalling is upregulated in PKD and rapamycin slows cyst expansion, whereas renal inactivation of the Tsc genes causes cysts. Here we identify a new interplay between the PKD and TSC genes, with important implications for the pathophysiology of both diseases. Kidney-specific inactivation of either Pkd1 or Tsc1 using an identical Cre (KspCre) results in aggressive or very mild PKD, respectively. Unexpectedly, we find that mTORC1 negatively regulates the biogenesis of polycystin-1 (PC-1) and trafficking of the PC-1/2 complex to cilia. Genetic interaction studies reveal an important role for PC-1 downregulation by mTORC1 in the cystogenesis of Tsc1 mutants. Our data potentially explain the severe renal manifestations of the TSC/PKD contiguous gene syndrome and open new perspectives for the use of mTOR inhibitors in autosomal dominant PKD caused by hypomorphic or missense PKD1 mutations.
منابع مشابه
Regulation of mTOR by polycystin-1: is polycystic kidney disease a case of futile repair?
Recent work has uncovered a functional link between polycystin-1 (PC1), the protein affected in autosomal-dominant polycystic kidney disease (ADPKD) and tuberin, the protein affected in tuberous sclerosis complex (TSC). These data suggest that PC1 functions by inducing the formation of a complex with tuberin and the Ser/Thr kinase mTOR thereby inhibiting mTOR activity. In normal, adult kidney, ...
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