@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 {991, title = {Mutations in transcription factor CP2-like 1 may cause a novel syndrome with distal renal tubulopathy in humans.}, journal = {Nephrol Dial Transplant}, volume = {36}, year = {2021}, month = {2021 01 25}, pages = {237-246}, abstract = {

BACKGROUND: An underlying monogenic cause of early-onset chronic kidney disease (CKD) can be detected in \~{}20\% of individuals. For many etiologies of CKD manifesting before 25 years of age, >200 monogenic causative genes have been identified to date, leading to the elucidation of mechanisms of renal pathogenesis.

METHODS: In 51 families with echogenic kidneys and CKD, we performed whole-exome sequencing to identify novel monogenic causes of CKD.

RESULTS: We discovered a homozygous truncating mutation in the transcription factor gene transcription factor CP2-like 1 (TFCP2L1) in an Arabic patient of consanguineous descent. The patient developed CKD by the age of 2 months and had episodes of severe hypochloremic, hyponatremic and hypokalemic alkalosis, seizures, developmental delay and hypotonia together with cataracts. We found that TFCP2L1~was localized throughout kidney development particularly in the distal nephron. Interestingly, TFCP2L1 induced the growth and development of renal tubules from rat mesenchymal cells. Conversely, the deletion of TFCP2L1~in mice was previously shown to lead to reduced expression of renal cell markers including ion transporters and cell identity proteins expressed in different segments of the distal nephron. TFCP2L1 localized to the nucleus in HEK293T cells only upon coexpression with its paralog upstream-binding protein 1 (UBP1). A TFCP2L1 mutant complementary DNA (cDNA) clone that represented the patient{\textquoteright}s mutation failed to form homo- and heterodimers with UBP1, an essential step for its transcriptional activity.

CONCLUSION: Here, we identified a loss-of-function TFCP2L1 mutation as a potential novel cause of CKD in childhood accompanied by a salt-losing tubulopathy.

}, keywords = {Animals, Child, DNA-Binding Proteins, Epithelial-Mesenchymal Transition, Female, HEK293 Cells, Humans, Kidney Diseases, Mice, Mice, Knockout, Mutation, Rats, Repressor Proteins, Single-Cell Analysis, Transcription Factors, Whole Exome Sequencing}, issn = {1460-2385}, doi = {10.1093/ndt/gfaa215}, author = {Kl{\"a}mbt, Verena and Werth, Max and Onuchic-Whitford, Ana C and Getwan, Maike and Kitzler, Thomas M and Buerger, Florian and Mao, Youying and Deutsch, Konstantin and Mann, Nina and Majmundar, Amar J and Kaminski, Michael M and Shen, Tian and Schmidt-Ott, Kai M and Shalaby, Mohamed and El Desoky, Sherif and Kari, Jameela A and Shril, Shirlee and Lienkamp, Soeren S and Barasch, Jonathan and Hildebrandt, Friedhelm} } @article {919, title = {DAAM2 Variants Cause Nephrotic Syndrome via Actin Dysregulation.}, journal = {Am J Hum Genet}, volume = {107}, year = {2020}, month = {2020 12 03}, pages = {1113-1128}, abstract = {

The discovery of >60 monogenic causes of nephrotic syndrome (NS) has revealed a central role for the actin regulators RhoA/Rac1/Cdc42 and their effectors, including the formin INF2. By whole-exome sequencing (WES), we here discovered bi-allelic variants in the formin DAAM2 in four unrelated families with steroid-resistant NS. We show that DAAM2 localizes to the cytoplasm in podocytes and in kidney sections. Further, the variants impair DAAM2-dependent actin remodeling processes: wild-type DAAM2 cDNA, but not cDNA representing missense variants found in individuals with NS, rescued reduced podocyte migration rate (PMR) and restored reduced filopodia formation in shRNA-induced DAAM2-knockdown podocytes. Filopodia restoration was also induced by the formin-activating molecule IMM-01. DAAM2 also co-localizes and co-immunoprecipitates with INF2, which is intriguing since variants in both formins cause NS. Using in~vitro bulk and TIRF microscopy assays, we find that DAAM2 variants alter actin assembly activities of the formin. In a Xenopus daam2-CRISPR knockout model, we demonstrate actin dysregulation in~vivo and glomerular maldevelopment that is rescued by WT-DAAM2 mRNA. We conclude that DAAM2 variants are a likely cause of monogenic human SRNS due to actin dysregulation in podocytes. Further, we provide evidence that DAAM2-associated SRNS may be amenable to treatment using actin regulating compounds.

}, keywords = {Actins, Alleles, Animals, Animals, Genetically Modified, Cell Movement, Cytoplasm, Formins, Genetic Variation, Humans, Kidney, Kidney Glomerulus, Microfilament Proteins, Mutation, Missense, Nephrotic Syndrome, Podocytes, Pseudopodia, rho GTP-Binding Proteins, RNA, Small Interfering, Whole Exome Sequencing, Xenopus}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2020.11.008}, author = {Schneider, Ronen and Deutsch, Konstantin and Hoeprich, Gregory J and Marquez, Jonathan and Hermle, Tobias and Braun, Daniela A and Seltzsam, Steve and Kitzler, Thomas M and Mao, Youying and Buerger, Florian and Majmundar, Amar J and Onuchic-Whitford, Ana C and Kolvenbach, Caroline M and Schierbaum, Luca and Schneider, Sophia and Halawi, Abdul A and Nakayama, Makiko and Mann, Nina and Connaughton, Dervla M and Kl{\"a}mbt, Verena and Wagner, Matias and Riedhammer, Korbinian M and Renders, Lutz and Katsura, Yoshichika and Thumkeo, Dean and Soliman, Neveen A and Mane, Shrikant and Lifton, Richard P and Shril, Shirlee and Khokha, Mustafa K and Hoefele, Julia and Goode, Bruce L and Hildebrandt, Friedhelm} } @article {907, title = {Mutations of the Transcriptional Corepressor ZMYM2 Cause Syndromic Urinary Tract Malformations.}, journal = {Am J Hum Genet}, volume = {107}, year = {2020}, month = {2020 10 01}, pages = {727-742}, abstract = {

Congenital anomalies of the kidney and urinary tract (CAKUT) constitute one of the most frequent birth defects and represent the most common cause of chronic kidney disease in the first three decades of life. Despite the discovery of dozens of monogenic causes of CAKUT, most pathogenic pathways remain elusive. We performed whole-exome sequencing (WES) in 551 individuals with CAKUT and identified a heterozygous de novo stop-gain variant in ZMYM2 in two different families with CAKUT. Through collaboration, we identified in total 14 different heterozygous loss-of-function mutations in ZMYM2 in 15 unrelated families. Most mutations occurred de novo, indicating possible interference with reproductive function. Human disease features are replicated in X.~tropicalis larvae with morpholino knockdowns, in which expression of truncated ZMYM2 proteins, based on individual mutations, failed to rescue renal and craniofacial defects. Moreover, heterozygous Zmym2-deficient mice recapitulated features of CAKUT with high penetrance. The ZMYM2 protein is a component of a transcriptional corepressor complex recently linked to the silencing of developmentally regulated endogenous retrovirus elements. Using protein-protein interaction assays, we show that ZMYM2 interacts with additional epigenetic silencing complexes, as well as confirming that it binds to FOXP1, a transcription factor that has also been linked to CAKUT. In summary, our findings establish that loss-of-function mutations of ZMYM2, and potentially that of other proteins in its interactome, as causes of human CAKUT, offering new routes for studying the pathogenesis of the disorder.

}, keywords = {Amphibian Proteins, Animals, Case-Control Studies, Child, Child, Preschool, DNA-Binding Proteins, Epigenesis, Genetic, Family, Female, Forkhead Transcription Factors, Heterozygote, Humans, Infant, Larva, Male, Mice, Mice, Knockout, Morpholinos, Mutation, Pedigree, Protein Binding, Repressor Proteins, Transcription Factors, Urinary Tract, Urogenital Abnormalities, Whole Exome Sequencing, Xenopus}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2020.08.013}, author = {Connaughton, Dervla M and Dai, Rufeng and Owen, Danielle J and Marquez, Jonathan and Mann, Nina and GrAHm-Paquin, Adda L and Nakayama, Makiko and Coyaud, Etienne and Laurent, Estelle M N and St-Germain, Jonathan R and Blok, Lot Snijders and Vino, Arianna and Kl{\"a}mbt, Verena and Deutsch, Konstantin and Wu, Chen-Han Wilfred and Kolvenbach, Caroline M and Kause, Franziska and Ottlewski, Isabel and Schneider, Ronen and Kitzler, Thomas M and Majmundar, Amar J and Buerger, Florian and Onuchic-Whitford, Ana C and Youying, Mao and Kolb, Amy and Salmanullah, Daanya and Chen, Evan and van der Ven, Amelie T and Rao, Jia and Ityel, Hadas and Seltzsam, Steve and Rieke, Johanna M and Chen, Jing and Vivante, Asaf and Hwang, Daw-Yang and Kohl, Stefan and Dworschak, Gabriel C and Hermle, Tobias and Alders, Marielle and Bartolomaeus, Tobias and Bauer, Stuart B and Baum, Michelle A and Brilstra, Eva H and Challman, Thomas D and Zyskind, Jacob and Costin, Carrie E and Dipple, Katrina M and Duijkers, Floor A and Ferguson, Marcia and FitzPatrick, David R and Fick, Roger and Glass, Ian A and Hulick, Peter J and Kline, Antonie D and Krey, Ilona and Kumar, Selvin and Lu, Weining and Marco, Elysa J and Wentzensen, Ingrid M and Mefford, Heather C and Platzer, Konrad and Povolotskaya, Inna S and Savatt, Juliann M and Shcherbakova, Natalia V and Senguttuvan, Prabha and Squire, Audrey E and Stein, Deborah R and Thiffault, Isabelle and Voinova, Victoria Y and Somers, Michael J G and Ferguson, Michael A and Traum, Avram Z and Daouk, Ghaleb H and Daga, Ankana and Rodig, Nancy M and Terhal, Paulien A and van Binsbergen, Ellen and Eid, Loai A and Tasic, Velibor and Rasouly, Hila Milo and Lim, Tze Y and Ahram, Dina F and Gharavi, Ali G and Reutter, Heiko M and Rehm, Heidi L and MacArthur, Daniel G and Lek, Monkol and Laricchia, Kristen M and Lifton, Richard P and Xu, Hong and Mane, Shrikant M and Sanna-Cherchi, Simone and Sharrocks, Andrew D and Raught, Brian and Fisher, Simon E and Bouchard, Maxime and Khokha, Mustafa K and Shril, Shirlee and Hildebrandt, Friedhelm} }