@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 {351, title = {Biallelic mutations in the 3{\textquoteright} exonuclease TOE1 cause pontocerebellar hypoplasia and uncover a role in snRNA processing.}, journal = {Nat Genet}, volume = {49}, year = {2017}, month = {2017 Mar}, pages = {457-464}, abstract = {

Deadenylases are best known for degrading the poly(A) tail during mRNA decay. The deadenylase family has expanded throughout evolution and, in mammals, consists of 12 Mg-dependent 3{\textquoteright}-end RNases with substrate specificity that is mostly unknown. Pontocerebellar hypoplasia type 7 (PCH7) is a unique recessive syndrome characterized by neurodegeneration and ambiguous genitalia. We studied 12 human families with PCH7, uncovering biallelic, loss-of-function mutations in TOE1, which encodes an unconventional deadenylase. toe1-morphant zebrafish displayed midbrain and hindbrain degeneration, modeling PCH-like structural defects in vivo. Surprisingly, we found that TOE1 associated with small nuclear RNAs (snRNAs) incompletely processed spliceosomal. These pre-snRNAs contained 3{\textquoteright} genome-encoded tails often followed by post-transcriptionally added adenosines. Human cells with reduced levels of TOE1 accumulated 3{\textquoteright}-end-extended pre-snRNAs, and the immunoisolated TOE1 complex was sufficient for 3{\textquoteright}-end maturation of snRNAs. Our findings identify the cause of a neurodegenerative syndrome linked to snRNA maturation and uncover a key factor involved in the processing of snRNA 3{\textquoteright} ends.

}, keywords = {Alleles, Animals, Cerebellar Diseases, Exonucleases, Female, Humans, Male, Mice, Mutation, Neurodegenerative Diseases, Nuclear Proteins, RNA, Messenger, RNA, Small Nuclear, Spliceosomes, Zebrafish}, issn = {1546-1718}, doi = {10.1038/ng.3762}, author = {Lardelli, Rea M and Schaffer, Ashleigh E and Eggens, Veerle R C and Zaki, Maha S and Grainger, Stephanie and Sathe, Shashank and Van Nostrand, Eric L and Schlachetzki, Zinayida and Rosti, Basak and Akizu, Naiara and Scott, Eric and Silhavy, Jennifer L and Heckman, Laura Dean and Rosti, Rasim Ozgur and Dikoglu, Esra and Gregor, Anne and Guemez-Gamboa, Alicia and Musaev, Damir and Mande, Rohit and Widjaja, Ari and Shaw, Tim L and Markmiller, Sebastian and Marin-Valencia, Isaac and Davies, Justin H and de Meirleir, Linda and Kayserili, H{\"u}lya and Altunoglu, Umut and Freckmann, Mary Louise and Warwick, Linda and Chitayat, David and Blaser, Susan and {\c C}a{\u g}layan, Ahmet Okay and Bilguvar, Kaya and Per, H{\"u}seyin and Fagerberg, Christina and Christesen, Henrik T and Kibaek, Maria and Aldinger, Kimberly A and Manchester, David and Matsumoto, Naomichi and Muramatsu, Kazuhiro and Saitsu, Hirotomo and Shiina, Masaaki and Ogata, Kazuhiro and Foulds, Nicola and Dobyns, William B and Chi, Neil C and Traver, David and Spaccini, Luigina and Bova, Stefania Maria and Gabriel, Stacey B and G{\"u}nel, Murat and Valente, Enza Maria and Nassogne, Marie-Cecile and Bennett, Eric J and Yeo, Gene W and Baas, Frank and Lykke-Andersen, Jens and Gleeson, Joseph G} } @article {382, title = {Homozygous Mutations in TBC1D23 Lead to a Non-degenerative Form of Pontocerebellar Hypoplasia.}, journal = {Am J Hum Genet}, volume = {101}, year = {2017}, month = {2017 Sep 07}, pages = {441-450}, abstract = {

Pontocerebellar hypoplasia (PCH) represents a group of recessive developmental disorders characterized by impaired growth of the pons and cerebellum, which frequently follows a degenerative course. Currently, there are 10 partially overlapping clinical subtypes and 13 genes known mutated in PCH. Here, we report biallelic TBC1D23 mutations in six individuals from four unrelated families manifesting a non-degenerative form of PCH. In addition to reduced volume of pons and cerebellum, affected individuals had microcephaly, psychomotor delay, and ataxia. In zebrafish, tbc1d23 morphants replicated the human phenotype showing hindbrain volume loss. TBC1D23 localized at the trans-Golgi and was regulated by the small GTPases Arl1 and Arl8, suggesting a role in trans-Golgi membrane trafficking. Altogether, this study provides a causative link between TBC1D23 mutations and PCH and suggests a less severe clinical course than other PCH subtypes.

}, keywords = {Adolescent, Animals, Cerebellar Diseases, Child, Child, Preschool, Female, GTPase-Activating Proteins, HeLa Cells, Homozygote, Humans, Male, Microcephaly, Mutation, Pedigree, Phenotype, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2017.07.015}, author = {Marin-Valencia, Isaac and Gerondopoulos, Andreas and Zaki, Maha S and Ben-Omran, Tawfeg and Almureikhi, Mariam and Demir, Ercan and Guemez-Gamboa, Alicia and Gregor, Anne and Issa, Mahmoud Y and Appelhof, Bart and Roosing, Susanne and Musaev, Damir and Rosti, Basak and Wirth, Sara and Stanley, Valentina and Baas, Frank and Barr, Francis A and Gleeson, Joseph G} } @article {252, title = {CLP1 founder mutation links tRNA splicing and maturation to cerebellar development and neurodegeneration.}, journal = {Cell}, volume = {157}, year = {2014}, month = {2014 Apr 24}, pages = {651-63}, abstract = {

Neurodegenerative diseases can occur so early as to affect neurodevelopment. From a cohort of more than 2,000 consanguineous families with childhood neurological disease, we identified a founder mutation in four independent pedigrees in cleavage and polyadenylation factor I subunit 1 (CLP1). CLP1 is a multifunctional kinase implicated in tRNA, mRNA, and siRNA maturation. Kinase activity of the CLP1 mutant protein was defective, and the tRNA endonuclease complex (TSEN) was destabilized, resulting in impaired pre-tRNA cleavage. Germline clp1 null zebrafish showed cerebellar neurodegeneration that was rescued by wild-type, but not mutant, human CLP1 expression. Patient-derived induced neurons displayed both depletion of mature tRNAs and accumulation of unspliced pre-tRNAs. Transfection of partially processed tRNA fragments into patient cells exacerbated an oxidative stress-induced reduction in cell survival. Our data link tRNA maturation to neuronal development and neurodegeneration through defective CLP1 function in humans.

}, keywords = {Animals, Brain, Cerebellum, Cleavage And Polyadenylation Specificity Factor, Female, Humans, Male, Mice, Models, Molecular, Neurodegenerative Diseases, Nuclear Proteins, Pedigree, Phosphotransferases, RNA Splicing, RNA, Transfer, Saccharomyces cerevisiae, Transcription Factors, Zebrafish, Zebrafish Proteins}, issn = {1097-4172}, doi = {10.1016/j.cell.2014.03.049}, author = {Schaffer, Ashleigh E and Eggens, Veerle R C and {\c C}a{\u g}layan, Ahmet Okay and Reuter, Miriam S and Scott, Eric and Coufal, Nicole G and Silhavy, Jennifer L and Xue, Yuanchao and Kayserili, H{\"u}lya and Yasuno, Katsuhito and Rosti, Rasim Ozgur and Abdellateef, Mostafa and Caglar, Caner and Kasher, Paul R and Cazemier, J Leonie and Weterman, Marian A and Cantagrel, Vincent and Cai, Na and Zweier, Christiane and Altunoglu, Umut and Satkin, N Bilge and Aktar, Fesih and Tuysuz, Beyhan and Yalcinkaya, Cengiz and Caksen, Huseyin and Bilguvar, Kaya and Fu, Xiang-Dong and Trotta, Christopher R and Gabriel, Stacey and Reis, Andr{\'e} and G{\"u}nel, Murat and Baas, Frank and Gleeson, Joseph G} }