@article {820, title = {Tyrosyl phosphorylation of PZR promotes hypertrophic cardiomyopathy in PTPN11-associated Noonan syndrome with multiple lentigines.}, journal = {JCI Insight}, volume = {5}, year = {2020}, month = {2020 08 06}, abstract = {

Noonan syndrome with multiple lentigines (NSML) is a rare autosomal dominant disorder that presents with cardio-cutaneous-craniofacial defects. Hypertrophic cardiomyopathy (HCM) represents the major life-threatening presentation in NSML. Mutations in the PTPN11 gene that encodes for the protein tyrosine phosphatase (PTP), SHP2, represents the predominant cause of HCM in NSML. NSML-associated PTPN11 mutations render SHP2 catalytically inactive with an "open" conformation. NSML-associated PTPN11 mutations cause hypertyrosyl phosphorylation of the transmembrane glycoprotein, protein zero-related (PZR), resulting in increased SHP2 binding. Here we show that NSML mice harboring a tyrosyl phosphorylation-defective mutant of PZR (NSML/PZRY242F) that is defective for SHP2 binding fail to develop HCM. Enhanced AKT/S6 kinase signaling in heart lysates of NSML mice was reversed in NSML/PZRY242F mice, demonstrating that PZR/SHP2 interactions promote aberrant AKT/S6 kinase activity in NSML. Enhanced PZR tyrosyl phosphorylation in the hearts of NSML mice was found to drive myocardial fibrosis by engaging an Src/NF-κB pathway, resulting in increased activation of IL-6. Increased expression of IL-6 in the hearts of NSML mice was reversed in NSML/PZRY242F mice, and PZRY242F mutant fibroblasts were defective for IL-6 secretion and STAT3-mediated fibrogenesis. These results demonstrate that NSML-associated PTPN11 mutations that induce PZR hypertyrosyl phosphorylation trigger pathophysiological signaling that promotes HCM and cardiac fibrosis.

}, keywords = {Animals, Cardiomyopathy, Hypertrophic, Disease Models, Animal, Female, Intracellular Signaling Peptides and Proteins, LEOPARD Syndrome, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Mutation, Myocytes, Cardiac, Phosphoproteins, Phosphorylation, Protein Tyrosine Phosphatase, Non-Receptor Type 11, Tyrosine}, issn = {2379-3708}, doi = {10.1172/jci.insight.137753}, author = {Yi, Jae-Sung and Perla, Sravan and Enyenihi, Liz and Bennett, Anton M} } @article {79, title = {DVL3 Alleles Resulting in a -1 Frameshift of the Last Exon Mediate Autosomal-Dominant Robinow Syndrome.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Mar 03}, pages = {553-561}, abstract = {

Robinow syndrome is a rare congenital disorder characterized by mesomelic limb shortening, genital hypoplasia, and distinctive facial features. Recent reports have identified, in individuals with dominant Robinow syndrome, a specific type of variant characterized by being uniformly located in the penultimate exon of DVL1 and resulting in a -1 frameshift allele with a premature termination codon that escapes nonsense-mediated decay. Here, we studied a cohort of individuals who had been clinically diagnosed with Robinow syndrome but who had not received a molecular diagnosis from variant studies of DVL1, WNT5A, and ROR2. Because of the uniform location of frameshift variants in DVL1-mediated Robinow syndrome and the functional redundancy of DVL1, DVL2, and DVL3, we elected to pursue direct Sanger sequencing of the penultimate exon of DVL1 and its paralogs DVL2 and DVL3 to search for potential disease-associated variants. Remarkably, targeted sequencing identified five unrelated individuals harboring heterozygous, de novo frameshift variants in DVL3, including two splice acceptor mutations and three 1 bp deletions. Similar to the variants observed in DVL1-mediated Robinow syndrome, all variants in DVL3 result in a -1 frameshift, indicating that these highly specific alterations might be a common cause of dominant Robinow syndrome. Here, we review the current knowledge of these peculiar variant alleles in DVL1- and DVL3-mediated Robinow syndrome and further elucidate the phenotypic features present in subjects with DVL1 and DVL3 frameshift mutations.

}, keywords = {Adaptor Proteins, Signal Transducing, Alleles, Base Sequence, Codon, Nonsense, Craniofacial Abnormalities, Dishevelled Proteins, Dwarfism, Exons, Female, Frameshift Mutation, Genetic Variation, Humans, Limb Deformities, Congenital, Male, Molecular Sequence Data, Phosphoproteins, Proto-Oncogene Proteins, Receptor Tyrosine Kinase-like Orphan Receptors, Sequence Analysis, DNA, Sequence Deletion, Urogenital Abnormalities, Wnt Proteins, Wnt-5a Protein}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.01.005}, author = {White, Janson J and Mazzeu, Juliana F and Hoischen, Alexander and Bayram, Yavuz and Withers, Marjorie and Gezdirici, Alper and Kimonis, Virginia and Steehouwer, Marloes and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and van Bon, Bregje W M and Sutton, V Reid and Lupski, James R and Brunner, Han G and Carvalho, Claudia M B} } @article {183, title = {DVL1 frameshift mutations clustering in the penultimate exon cause autosomal-dominant Robinow syndrome.}, journal = {Am J Hum Genet}, volume = {96}, year = {2015}, month = {2015 Apr 02}, pages = {612-22}, abstract = {

Robinow syndrome is a genetically heterogeneous disorder characterized by mesomelic limb shortening, genital hypoplasia, and distinctive facial features and for which both autosomal-recessive and autosomal-dominant inheritance patterns have been described. Causative variants in the non-canonical signaling gene WNT5A underlie a subset of autosomal-dominant Robinow syndrome (DRS) cases, but most individuals with DRS remain without a molecular diagnosis. We performed whole-exome sequencing in four unrelated DRS-affected individuals without coding mutations in WNT5A and found heterozygous DVL1 exon 14 mutations in three of them. Targeted Sanger sequencing in additional subjects with DRS uncovered DVL1 exon 14 mutations in five individuals, including a pair of monozygotic twins. In total, six distinct frameshift mutations were found in eight subjects, and all were heterozygous truncating variants within the penultimate exon of DVL1. In five families in which samples from unaffected parents were available, the variants were demonstrated to represent de novo mutations. All variant alleles are predicted to result in a premature termination codon within the last exon, escape nonsense-mediated decay (NMD), and most likely generate a C-terminally truncated protein with a distinct -1 reading-frame terminus. Study of the transcripts extracted from affected subjects{\textquoteright} leukocytes confirmed expression of both wild-type and variant alleles, supporting the hypothesis that mutant mRNA escapes NMD. Genomic variants identified in our study suggest that truncation of the C-terminal domain of DVL1, a protein hypothesized to have a downstream role in the Wnt-5a non-canonical pathway, is a common cause of DRS.

}, keywords = {Adaptor Proteins, Signal Transducing, Amino Acid Sequence, Base Sequence, Craniofacial Abnormalities, Dishevelled Proteins, DNA Primers, Dwarfism, Exome, Exons, Frameshift Mutation, Gene Components, Humans, Limb Deformities, Congenital, Molecular Sequence Data, Phosphoproteins, Sequence Analysis, DNA, Urogenital Abnormalities}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.02.015}, author = {White, Janson and Mazzeu, Juliana F and Hoischen, Alexander and Jhangiani, Shalini N and Gambin, Tomasz and Alcino, Michele Calijorne and Penney, Samantha and Saraiva, Jorge M and Hove, Hanne and Skovby, Flemming and Kayserili, H{\"u}lya and Estrella, Elicia and Vulto-van Silfhout, Anneke T and Steehouwer, Marloes and Muzny, Donna M and Sutton, V Reid and Gibbs, Richard A and Lupski, James R and Brunner, Han G and van Bon, Bregje W M and Carvalho, Claudia M B} } @article {196, title = {Mutations in RAD21 disrupt regulation of APOB in patients with chronic intestinal pseudo-obstruction.}, journal = {Gastroenterology}, volume = {148}, year = {2015}, month = {2015 Apr}, pages = {771-782.e11}, abstract = {

BACKGROUND \& AIMS: Chronic intestinal pseudo-obstruction (CIPO) is characterized by severe intestinal dysmotility that mimics a mechanical subocclusion with no~evidence of gut obstruction. We searched for genetic variants associated with CIPO to increase our understanding of its pathogenesis and to identify potential biomarkers.

METHODS: We performed whole-exome sequencing of genomic DNA from patients with familial CIPO syndrome. Blood and lymphoblastoid cells were collected from patients and controls (individuals without CIPO); levels of messenger RNA (mRNA) and proteins were analyzed by quantitative reverse-transcription polymerase chain reaction, immunoblot, and mobility shift assays. Complementary DNAs were transfected into HEK293 cells. Expression of rad21 was suppressed in zebrafish embryos using a splice-blocking morpholino (rad21a). Gut tissues were collected and analyzed.

RESULTS: We identified a homozygous mutation (p.622, encodes Ala>Thr) in RAD21 in patients from a consanguineous family with CIPO. Expression of RUNX1, a target of RAD21, was reduced in cells from patients with CIPO compared with controls. In zebrafish, suppression of rad21a reduced expression of runx1; this phenotype was corrected by injection of human RAD21 mRNA, but not with the mRNA from the mutated p.622 allele. rad21a Morpholino zebrafish had delayed intestinal transit and greatly reduced numbers of enteric neurons, similar to patients with CIPO. This defect was greater in zebrafish with suppressed expression of ret and rad21, indicating their interaction in the regulation of gut neurogenesis. The promoter region of APOB bound RAD21 but not RAD21 p.622 Ala>Thr; expression of wild-type RAD21 in HEK293 cells repressed expression of APOB, compared with control vector. The gut-specific isoform of APOB (APOB48) is overexpressed in sera from patients with CIPO who carry the RAD21 mutation. APOB48 also is overexpressed in sporadic CIPO in sera and gut biopsy specimens.

CONCLUSIONS: Some patients with CIPO carry mutations in RAD21 that disrupt the ability of its product to regulate genes such as RUNX1 and APOB. Reduced expression of rad21 in zebrafish, and dysregulation of these target genes, disrupts intestinal transit and the development of enteric neurons.

}, keywords = {Adult, Animals, Apolipoprotein B-100, Case-Control Studies, Cell Cycle Proteins, Chronic Disease, Core Binding Factor Alpha 2 Subunit, Enteric Nervous System, Female, Gastrointestinal Motility, Gene Expression Profiling, Gene Knockdown Techniques, HEK293 Cells, Humans, Intestinal Pseudo-Obstruction, Male, Middle Aged, Nuclear Proteins, Phosphoproteins, RNA, Messenger, Sequence Analysis, DNA, Young Adult, Zebrafish, Zebrafish Proteins}, issn = {1528-0012}, doi = {10.1053/j.gastro.2014.12.034}, author = {Bonora, Elena and Bianco, Francesca and Cordeddu, Lina and Bamshad, Michael and Francescatto, Ludmila and Dowless, Dustin and Stanghellini, Vincenzo and Cogliandro, Rosanna F and Lindberg, Greger and Mungan, Zeynel and Cefle, Kivanc and Ozcelik, Tayfun and Palanduz, Sukru and Ozturk, Sukru and Gedikbasi, Asuman and Gori, Alessandra and Pippucci, Tommaso and Graziano, Claudio and Volta, Umberto and Caio, Giacomo and Barbara, Giovanni and D{\textquoteright}Amato, Mauro and Seri, Marco and Katsanis, Nicholas and Romeo, Giovanni and De Giorgio, Roberto} } @article {209, title = {Dosage changes of a segment at 17p13.1 lead to intellectual disability and microcephaly as a result of complex genetic interaction of multiple genes.}, journal = {Am J Hum Genet}, volume = {95}, year = {2014}, month = {2014 Nov 06}, pages = {565-78}, abstract = {

The 17p13.1 microdeletion syndrome is a recently described genomic disorder with a core clinical phenotype of intellectual disability, poor to absent speech, dysmorphic features, and a constellation of more variable clinical features, most prominently microcephaly. We identified five subjects with copy-number variants (CNVs) on 17p13.1 for whom we performed detailed clinical and molecular studies. Breakpoint mapping and retrospective analysis of published cases refined the smallest region of overlap (SRO) for microcephaly to a genomic interval containing nine genes. Dissection of this phenotype in zebrafish embryos revealed a complex genetic architecture: dosage perturbation of four genes (ASGR1, ACADVL, DVL2, and GABARAP) impeded neurodevelopment and decreased dosage of the same loci caused a reduced mitotic index in~vitro. Moreover, epistatic analyses in~vivo showed that dosage perturbations of discrete gene pairings induce microcephaly. Taken together, these studies support a model in which concomitant dosage perturbation of multiple genes within the CNV drive the microcephaly and possibly other neurodevelopmental phenotypes associated with rearrangements in the 17p13.1 SRO.

}, keywords = {Abnormalities, Multiple, Acyl-CoA Dehydrogenase, Long-Chain, Adaptor Proteins, Signal Transducing, Animals, Asialoglycoprotein Receptor, Base Sequence, Cell Line, Chromosome Breakpoints, Chromosome Deletion, Chromosomes, Human, Pair 17, Dishevelled Proteins, Flow Cytometry, Gene Dosage, Humans, Immunohistochemistry, Intellectual Disability, Microcephaly, Microtubule-Associated Proteins, Molecular Sequence Data, Phosphoproteins, Retrospective Studies, Sequence Analysis, DNA, Smith-Magenis Syndrome, Syndrome, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.10.006}, author = {Carvalho, Claudia M B and Vasanth, Shivakumar and Shinawi, Marwan and Russell, Chad and Ramocki, Melissa B and Brown, Chester W and Graakjaer, Jesper and Skytte, Anne-Bine and Vianna-Morgante, Angela M and Krepischi, Ana C V and Patel, Gayle S and Immken, LaDonna and Aleck, Kyrieckos and Lim, Cynthia and Cheung, Sau Wai and Rosenberg, Carla and Katsanis, Nicholas and Lupski, James R} }