The trafficking dynamics of uromodulin (UMOD), the most abundant protein in human urine, play a critical role in the pathogenesis of kidney disease. Monoallelic mutations in the UMOD gene cause autosomal dominant tubulointerstitial kidney disease (ADTKD-UMOD), an incurable genetic disorder that leads to kidney failure. The disease is caused by the intracellular entrapment of mutant UMOD in kidney epithelial cells, but the precise mechanisms mediating disrupted UMOD trafficking remain elusive. Here, we report that transmembrane Emp24 protein transport domain-containing (TMED) cargo receptors TMED2, TMED9, and TMED10 bind UMOD and regulate its trafficking along the secretory pathway. Pharmacological targeting of TMEDs in cells, in human kidney organoids derived from patients with ADTKD-UMOD, and in mutant-UMOD-knockin mice reduced intracellular accumulation of mutant UMOD and restored trafficking and localization of UMOD to the apical plasma membrane. In vivo, the TMED-targeted small molecule also mitigated ER stress and markers of kidney damage and fibrosis. Our work reveals TMED-targeting small molecules as a promising therapeutic strategy for kidney proteinopathies.

• Klíčová slova
• Genetic diseases, Nephrology, Protein misfolding, Protein traffic,
• MeSH
• lidé MeSH
• membránové glykoproteiny metabolismus   genetika   MeSH
• mutace MeSH
• myši MeSH
• transport proteinů * MeSH
• uromodulin * metabolismus   genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• membránové glykoproteiny MeSH
• UMOD protein, human MeSH Prohlížeč
• Umod protein, mouse MeSH Prohlížeč
• uromodulin * MeSH

Autosomal-dominant tubulo-interstitial kidney disease (ADTKD) encompasses a group of disorders characterized by renal tubular and interstitial abnormalities, leading to slow progressive loss of kidney function requiring dialysis and kidney transplantation. Mutations in UMOD, MUC1, and REN are responsible for many, but not all, cases of ADTKD. We report on two families with ADTKD and congenital anemia accompanied by either intrauterine growth retardation or neutropenia. Ultrasound and kidney biopsy revealed small dysplastic kidneys with cysts and tubular atrophy with secondary glomerular sclerosis, respectively. Exclusion of known ADTKD genes coupled with linkage analysis, whole-exome sequencing, and targeted re-sequencing identified heterozygous missense variants in SEC61A1-c.553A>G (p.Thr185Ala) and c.200T>G (p.Val67Gly)-both affecting functionally important and conserved residues in SEC61. Both transiently expressed SEC6A1A variants are delocalized to the Golgi, a finding confirmed in a renal biopsy from an affected individual. Suppression or CRISPR-mediated deletions of sec61al2 in zebrafish embryos induced convolution defects of the pronephric tubules but not the pronephric ducts, consistent with the tubular atrophy observed in the affected individuals. Human mRNA encoding either of the two pathogenic alleles failed to rescue this phenotype as opposed to a complete rescue by human wild-type mRNA. Taken together, these findings provide a mechanism by which mutations in SEC61A1 lead to an autosomal-dominant syndromic form of progressive chronic kidney disease. We highlight protein translocation defects across the endoplasmic reticulum membrane, the principal role of the SEC61 complex, as a contributory pathogenic mechanism for ADTKD.

• MeSH
• alely MeSH
• anemie genetika   MeSH
• biopsie MeSH
• chronická nemoc MeSH
• dánio pruhované embryologie   genetika   MeSH
• dítě MeSH
• dominantní geny MeSH
• dospělí MeSH
• endoplazmatické retikulum metabolismus   MeSH
• exom genetika   MeSH
• fenotyp MeSH
• Golgiho aparát metabolismus   MeSH
• heterozygot * MeSH
• lidé středního věku MeSH
• lidé MeSH
• messenger RNA analýza   genetika   MeSH
• missense mutace genetika   MeSH
• mladý dospělý MeSH
• molekulární modely MeSH
• mutace * MeSH
• nemoci ledvin genetika   patologie   MeSH
• neutropenie genetika   MeSH
• novorozenec MeSH
• progrese nemoci MeSH
• rodokmen MeSH
• růstová retardace plodu genetika   MeSH
• sekvence aminokyselin MeSH
• senioři MeSH
• syndrom MeSH
• translokační kanály SEC chemie   genetika   MeSH
• zvířata MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• senioři MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• messenger RNA MeSH
• SEC61A1 protein, human MeSH Prohlížeč
• translokační kanály SEC MeSH