@article {963, title = {Absent B cells, agammaglobulinemia, and hypertrophic cardiomyopathy in folliculin-interacting protein 1 deficiency.}, journal = {Blood}, volume = {137}, year = {2021}, month = {2021 01 28}, pages = {493-499}, abstract = {

Agammaglobulinemia is the most profound primary antibody deficiency that can occur due to an early termination of B-cell development. We here investigated 3 novel patients, including the first known adult, from unrelated families with agammaglobulinemia, recurrent infections, and hypertrophic cardiomyopathy (HCM). Two of them also presented with intermittent or severe chronic neutropenia. We identified homozygous or compound-heterozygous variants in the gene for folliculin interacting protein 1 (FNIP1), leading to loss of the FNIP1 protein. B-cell metabolism, including mitochondrial numbers and activity and phosphatidylinositol 3-kinase/AKT pathway, was impaired. These defects recapitulated the Fnip1-/- animal model. Moreover, we identified either uniparental disomy or copy-number variants (CNVs) in 2 patients, expanding the variant spectrum of this novel inborn error of immunity. The results indicate that FNIP1 deficiency can be caused by complex genetic mechanisms and support the clinical utility of exome sequencing and CNV analysis in patients with broad phenotypes, including agammaglobulinemia and HCM. FNIP1 deficiency is a novel inborn error of immunity characterized by early and severe B-cell development defect, agammaglobulinemia, variable neutropenia, and HCM. Our findings elucidate a functional and relevant role of FNIP1 in B-cell development and metabolism and potentially neutrophil activity.

}, keywords = {Adult, Agammaglobulinemia, Animals, B-Lymphocytes, Cardiomyopathy, Hypertrophic, Carrier Proteins, Child, Child, Preschool, Chromosomes, Human, Pair 5, Codon, Nonsense, Consanguinity, Crohn Disease, Developmental Disabilities, Disease Models, Animal, Disease Susceptibility, DNA Copy Number Variations, Female, Heart Defects, Congenital, Humans, Immunologic Deficiency Syndromes, Infections, Loss of Function Mutation, Lymphopenia, Male, Mice, Neutropenia, Pedigree, Uniparental Disomy, Whole Exome Sequencing}, issn = {1528-0020}, doi = {10.1182/blood.2020006441}, author = {Saettini, Francesco and Poli, Cecilia and Vengoechea, Jaime and Bonanomi, Sonia and Orellana, Julio C and Fazio, Grazia and Rodriguez, Fred H and Noguera, Loreani P and Booth, Claire and Jarur-Chamy, Valentina and Shams, Marissa and Iascone, Maria and Vukic, Maja and Gasperini, Serena and Quadri, Manuel and Barroeta Seijas, Amairelys and Rivers, Elizabeth and Mauri, Mario and Badolato, Raffaele and Cazzaniga, Gianni and Bugarin, Cristina and Gaipa, Giuseppe and Kroes, Wilma G M and Moratto, Daniele and van Oostaijen-Ten Dam, Monique M and Baas, Frank and van der Maarel, Silv{\`e}re and Piazza, Rocco and Coban-Akdemir, Zeynep H and Lupski, James R and Yuan, Bo and Chinn, Ivan K and Daxinger, Lucia and Biondi, Andrea} } @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 {613, title = {A novel NAA10 variant with impaired acetyltransferase activity causes developmental delay, intellectual disability, and hypertrophic cardiomyopathy.}, journal = {Eur J Hum Genet}, volume = {26}, year = {2018}, month = {2018 09}, pages = {1294-1305}, abstract = {

The NAA10-NAA15 complex (NatA) is an N-terminal acetyltransferase that catalyzes N-terminal acetylation of ~40\% of all human proteins. N-terminal acetylation has several different roles in the cell, including altering protein stability and degradation, protein localization and protein-protein interactions. In recent years several X-linked NAA10 variants have been associated with genetic disorders. We have identified a previously undescribed NAA10 c.215T>C p.(Ile72Thr) variant in three boys from two unrelated families with a milder phenotypic spectrum in comparison to most of the previously described patients with NAA10 variants. These boys have development delay, intellectual disability, and cardiac abnormalities as overlapping phenotypes. Functional studies reveal that NAA10 Ile72Thr is destabilized, while binding to NAA15 most likely is intact. Surprisingly, the NatA activity of NAA10 Ile72Thr appears normal while its monomeric activity is decreased. This study further broadens the phenotypic spectrum associated with NAA10 deficiency, and adds to the evidence that genotype-phenotype correlations for NAA10 variants are much more complex than initially anticipated.

}, keywords = {Cardiomyopathy, Hypertrophic, Child, Preschool, Developmental Disabilities, Enzyme Stability, HeLa Cells, Humans, Infant, Intellectual Disability, Male, Mutation, N-Terminal Acetyltransferase A, N-Terminal Acetyltransferase E, Phenotype, Protein Binding, Syndrome}, issn = {1476-5438}, doi = {10.1038/s41431-018-0136-0}, author = {St{\o}ve, Svein Isungset and Blenski, Marina and Stray-Pedersen, Asbj{\o}rg and Wierenga, Klaas J and Jhangiani, Shalini N and Akdemir, Zeynep Coban and Crawford, David and McTiernan, Nina and Myklebust, Line M and Purcarin, Gabriela and McNall-Knapp, Rene and Wadley, Alexandrea and Belmont, John W and Kim, Jeffrey J and Lupski, James R and Arnesen, Thomas} }