@article {1007, title = {De novo TRIM8 variants impair its protein localization to nuclear bodies and cause developmental delay, epilepsy, and focal segmental glomerulosclerosis.}, journal = {Am J Hum Genet}, volume = {108}, year = {2021}, month = {2021 02 04}, pages = {357-367}, abstract = {

Focal segmental glomerulosclerosis (FSGS) is the main pathology underlying steroid-resistant nephrotic syndrome (SRNS) and a leading cause of chronic kidney disease. Monogenic forms of pediatric SRNS are predominantly caused by recessive mutations, while the contribution of de novo variants (DNVs) to this trait is poorly understood. Using exome sequencing (ES) in a proband with FSGS/SRNS, developmental delay, and epilepsy, we discovered a nonsense DNV in TRIM8, which encodes the E3 ubiquitin ligase tripartite motif containing 8. To establish whether TRIM8 variants represent a cause of FSGS, we aggregated exome/genome-sequencing data for 2,501 pediatric FSGS/SRNS-affected individuals and 48,556 control subjects, detecting eight heterozygous TRIM8 truncating variants in affected subjects but none in control subjects (p = 3.28~{\texttimes} 10). In all six cases with available parental DNA, we demonstrated de novo inheritance (p~=~2.21~{\texttimes} 10). Reverse phenotyping revealed neurodevelopmental disease in all eight families. We next analyzed ES from 9,067 individuals with epilepsy, yielding three additional families with truncating TRIM8 variants. Clinical review revealed FSGS in all. All TRIM8 variants cause protein truncation clustering within the last exon between residues 390 and 487 of the 551 amino acid protein, indicating a correlation between this syndrome and loss of the TRIM8 C-terminal region. Wild-type TRIM8 overexpressed in immortalized human podocytes and neuronal cells localized to nuclear bodies, while constructs harboring patient-specific variants mislocalized diffusely to the nucleoplasm. Co-localization studies demonstrated that Gemini and Cajal bodies frequently abut a TRIM8 nuclear body. Truncating TRIM8 DNVs cause a neuro-renal syndrome via aberrant TRIM8 localization, implicating nuclear bodies in FSGS and developmental brain disease.

}, keywords = {Adult, Animals, Carrier Proteins, Cell Line, Child, Child, Preschool, Codon, Nonsense, Developmental Disabilities, Epilepsy, Female, Glomerulosclerosis, Focal Segmental, Humans, Intranuclear Space, Kidney, Male, Mice, Mutation, Nephrotic Syndrome, Nerve Tissue Proteins, Phenotype, Podocytes, Whole Exome Sequencing}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2021.01.008}, author = {Weng, Patricia L and Majmundar, Amar J and Khan, Kamal and Lim, Tze Y and Shril, Shirlee and Jin, Gina and Musgrove, John and Wang, Minxian and Ahram, Dina F and Aggarwal, Vimla S and Bier, Louise E and Heinzen, Erin L and Onuchic-Whitford, Ana C and Mann, Nina and Buerger, Florian and Schneider, Ronen and Deutsch, Konstantin and Kitzler, Thomas M and Kl{\"a}mbt, Verena and Kolb, Amy and Mao, Youying and Moufawad El Achkar, Christelle and Mitrotti, Adele and Martino, Jeremiah and Beck, Bodo B and Altm{\"u}ller, Janine and Benz, Marcus R and Yano, Shoji and Mikati, Mohamad A and Gunduz, Talha and Cope, Heidi and Shashi, Vandana and Trachtman, Howard and Bodria, Monica and Caridi, Gianluca and Pisani, Isabella and Fiaccadori, Enrico and AbuMaziad, Asmaa S and Martinez-Agosto, Julian A and Yadin, Ora and Zuckerman, Jonathan and Kim, Arang and John-Kroegel, Ulrike and Tyndall, Amanda V and Parboosingh, Jillian S and Innes, A Micheil and Bierzynska, Agnieszka and Koziell, Ania B and Muorah, Mordi and Saleem, Moin A and Hoefele, Julia and Riedhammer, Korbinian M and Gharavi, Ali G and Jobanputra, Vaidehi and Pierce-Hoffman, Emma and Seaby, Eleanor G and O{\textquoteright}Donnell-Luria, Anne and Rehm, Heidi L and Mane, Shrikant and D{\textquoteright}Agati, Vivette D and Pollak, Martin R and Ghiggeri, Gian Marco and Lifton, Richard P and Goldstein, David B and Davis, Erica E and Hildebrandt, Friedhelm and Sanna-Cherchi, Simone} } @article {80, title = {FAT1 mutations cause a glomerulotubular nephropathy.}, journal = {Nat Commun}, volume = {7}, year = {2016}, month = {2016 Feb 24}, pages = {10822}, abstract = {

Steroid-resistant nephrotic syndrome (SRNS) causes 15\% of chronic kidney disease (CKD). Here we show that recessive mutations in FAT1 cause a distinct renal disease entity in four families with a combination of SRNS, tubular ectasia, haematuria and facultative neurological involvement. Loss of FAT1 results in decreased cell adhesion and migration in fibroblasts and podocytes and the decreased migration is partially reversed by a RAC1/CDC42 activator. Podocyte-specific deletion of Fat1 in mice induces abnormal glomerular filtration barrier development, leading to podocyte foot process effacement. Knockdown of Fat1 in renal tubular cells reduces migration, decreases active RAC1 and CDC42, and induces defects in lumen formation. Knockdown of fat1 in zebrafish causes pronephric cysts, which is partially rescued by RAC1/CDC42 activators, confirming a role of the two small GTPases in the pathogenesis. These findings provide new insights into the pathogenesis of SRNS and tubulopathy, linking FAT1 and RAC1/CDC42 to podocyte and tubular cell function.

}, keywords = {Animals, Cadherins, cdc42 GTP-Binding Protein, Cell Adhesion, Cell Movement, Dilatation, Pathologic, Fibroblasts, Gene Knockdown Techniques, Hematuria, Humans, Kidney Tubules, Lissencephaly, Mice, Mutation, Nephrotic Syndrome, Podocytes, rac1 GTP-Binding Protein, Syndrome, Zebrafish, Zebrafish Proteins}, issn = {2041-1723}, doi = {10.1038/ncomms10822}, author = {Gee, Heon Yung and Sadowski, Carolin E and Aggarwal, Pardeep K and Porath, Jonathan D and Yakulov, Toma A and Schueler, Markus and Lovric, Svjetlana and Ashraf, Shazia and Braun, Daniela A and Halbritter, Jan and Fang, Humphrey and Airik, Rannar and Vega-Warner, Virginia and Cho, Kyeong Jee and Chan, Timothy A and Morris, Luc G T and ffrench-Constant, Charles and Allen, Nicholas and McNeill, Helen and B{\"u}scher, Rainer and Kyrieleis, Henriette and Wallot, Michael and Gaspert, Ariana and Kistler, Thomas and Milford, David V and Saleem, Moin A and Keng, Wee Teik and Alexander, Stephen I and Valentini, Rudolph P and Licht, Christoph and Teh, Jun C and Bogdanovic, Radovan and Koziell, Ania and Bierzynska, Agnieszka and Soliman, Neveen A and Otto, Edgar A and Lifton, Richard P and Holzman, Lawrence B and Sibinga, Nicholas E S and Walz, Gerd and Tufro, Alda and Hildebrandt, Friedhelm} } @article {282, title = {ADCK4 mutations promote steroid-resistant nephrotic syndrome through CoQ10 biosynthesis disruption.}, journal = {J Clin Invest}, volume = {123}, year = {2013}, month = {2013 Dec}, pages = {5179-89}, abstract = {

Identification of single-gene causes of steroid-resistant nephrotic syndrome (SRNS) has furthered the understanding of the pathogenesis of this disease. Here, using a combination of homozygosity mapping and whole human exome resequencing, we identified mutations in the aarF domain containing kinase 4 (ADCK4) gene in 15 individuals with SRNS from 8 unrelated families. ADCK4 was highly similar to ADCK3, which has been shown to participate in coenzyme Q10 (CoQ10) biosynthesis. Mutations in ADCK4 resulted in reduced CoQ10 levels and reduced mitochondrial respiratory enzyme activity in cells isolated from individuals with SRNS and transformed lymphoblasts. Knockdown of adck4 in zebrafish and Drosophila recapitulated nephrotic syndrome-associated phenotypes. Furthermore, ADCK4 was expressed in glomerular podocytes and partially localized to podocyte mitochondria and foot processes in rat kidneys and cultured human podocytes. In human podocytes, ADCK4 interacted with members of the CoQ10 biosynthesis pathway, including COQ6, which has been linked with SRNS and COQ7. Knockdown of ADCK4 in podocytes resulted in decreased migration, which was reversed by CoQ10 addition. Interestingly, a patient with SRNS with a homozygous ADCK4 frameshift mutation had partial remission following CoQ10 treatment. These data indicate that individuals with SRNS with mutations in ADCK4 or other genes that participate in CoQ10 biosynthesis may be treatable with CoQ10.

}, keywords = {Adolescent, Adrenal Cortex Hormones, Amino Acid Sequence, Animals, Cells, Cultured, Child, Consanguinity, Conserved Sequence, Disease Models, Animal, DNA Mutational Analysis, Drosophila Proteins, Drug Resistance, Exome, Fibroblasts, Gene Knockdown Techniques, Humans, Mitochondria, Molecular Sequence Data, Mutation, Nephrotic Syndrome, Podocytes, Protein Kinases, Rats, Sequence Alignment, Sequence Homology, Amino Acid, Ubiquinone, Young Adult, Zebrafish, Zebrafish Proteins}, issn = {1558-8238}, doi = {10.1172/JCI69000}, author = {Ashraf, Shazia and Gee, Heon Yung and Woerner, Stephanie and Xie, Letian X and Vega-Warner, Virginia and Lovric, Svjetlana and Fang, Humphrey and Song, Xuewen and Cattran, Daniel C and Avila-Casado, Carmen and Paterson, Andrew D and Nitschk{\'e}, Patrick and Bole-Feysot, Christine and Cochat, Pierre and Esteve-Rudd, Julian and Haberberger, Birgit and Allen, Susan J and Zhou, Weibin and Airik, Rannar and Otto, Edgar A and Barua, Moumita and Al-Hamed, Mohamed H and Kari, Jameela A and Evans, Jonathan and Bierzynska, Agnieszka and Saleem, Moin A and Bockenhauer, Detlef and Kleta, Robert and El Desoky, Sherif and Hacihamdioglu, Duygu O and Gok, Faysal and Washburn, Joseph and Wiggins, Roger C and Choi, Murim and Lifton, Richard P and Levy, Shawn and Han, Zhe and Salviati, Leonardo and Prokisch, Holger and Williams, David S and Pollak, Martin and Clarke, Catherine F and Pei, York and Antignac, Corinne and Hildebrandt, Friedhelm} }