@article {804, title = {Loss of NARS1 impairs progenitor proliferation in cortical brain organoids and leads to microcephaly.}, journal = {Nat Commun}, volume = {11}, year = {2020}, month = {2020 08 12}, pages = {4038}, abstract = {

Asparaginyl-tRNA synthetase1 (NARS1) is a member of the ubiquitously expressed cytoplasmic Class IIa family of tRNA synthetases required for protein translation. Here, we identify biallelic missense and frameshift mutations in NARS1 in seven patients from three unrelated families with microcephaly and neurodevelopmental delay. Patient cells show reduced NARS1 protein, impaired NARS1 activity and impaired global protein synthesis. Cortical brain organoid modeling shows reduced proliferation of radial glial cells (RGCs), leading to smaller organoids characteristic of microcephaly. Single-cell analysis reveals altered constituents of both astrocytic and RGC lineages, suggesting a requirement for NARS1 in RGC proliferation. Our findings demonstrate that NARS1 is required to meet protein synthetic needs and to support RGC proliferation in human brain development.

}, keywords = {Adolescent, Adult, Aspartate-tRNA Ligase, Base Sequence, Cell Differentiation, Cell Proliferation, Cell Size, Cell Survival, Cerebral Cortex, Child, Family, Female, Fibroblasts, HEK293 Cells, Humans, Induced Pluripotent Stem Cells, Ki-67 Antigen, Male, Microcephaly, Mutation, Neural Stem Cells, Neuroglia, Organoids, Pedigree, RNA, Transfer, Amino Acyl, Young Adult}, issn = {2041-1723}, doi = {10.1038/s41467-020-17454-4}, author = {Wang, Lu and Li, Zhen and Sievert, David and Smith, Desir{\'e}e E C and Mendes, Marisa I and Chen, Dillon Y and Stanley, Valentina and Ghosh, Shereen and Wang, Yulu and Kara, Majdi and Aslanger, Ayca Dilruba and Rosti, Rasim O and Houlden, Henry and Salomons, Gajja S and Gleeson, Joseph G} } @article {494, title = {A homozygous founder mutation in associates with a neurodevelopmental disorder characterised by microcephaly, epilepsy and autistic features.}, journal = {J Med Genet}, volume = {55}, year = {2018}, month = {2018 01}, pages = {48-54}, abstract = {

BACKGROUND: Transport protein particle (TRAPP) is a multisubunit complex that regulates membrane trafficking through the Golgi apparatus. The clinical phenotype associated with mutations in various TRAPP subunits has allowed elucidation of their functions in specific tissues. The role of some subunits in human disease, however, has not been fully established, and their functions remain uncertain.

OBJECTIVE: We aimed to expand the range of neurodevelopmental disorders associated with mutations in TRAPP subunits by exome sequencing of consanguineous families.

METHODS: Linkage and homozygosity mapping and candidate gene analysis were used to identify homozygous mutations in families. Patient fibroblasts were used to study splicing defect and zebrafish to model the disease.

RESULTS: We identified six individuals from three unrelated families with a founder homozygous splice mutation in , encoding a core subunit of the complex TRAPP I. Patients manifested a neurodevelopmental disorder characterised by microcephaly, epilepsy and autistic features, and showed splicing defect. Zebrafish morphants replicated the human phenotype, displaying decreased head size and neuronal hyperexcitability, leading to a lower seizure threshold.

CONCLUSION: This study provides clinical and functional evidence of the role of in brain development and function.

}, keywords = {Animals, Autistic Disorder, Epilepsy, Founder Effect, Genetic Association Studies, Homozygote, Humans, Microcephaly, Mutation, Neurodevelopmental Disorders, Phenotype, Vesicular Transport Proteins, Zebrafish}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2017-104627}, author = {Marin-Valencia, Isaac and Novarino, Gaia and Johansen, Anide and Rosti, Basak and Issa, Mahmoud Y and Musaev, Damir and Bhat, Gifty and Scott, Eric and Silhavy, Jennifer L and Stanley, Valentina and Rosti, Rasim O and Gleeson, Jeremy W and Imam, Farhad B and Zaki, Maha S and Gleeson, Joseph G} } @article {37, title = {Biallelic Mutations in Citron Kinase Link Mitotic Cytokinesis to Human Primary Microcephaly.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Aug 04}, pages = {501-10}, abstract = {

Cell division terminates with cytokinesis and cellular separation. Autosomal-recessive primary microcephaly (MCPH) is a neurodevelopmental disorder characterized by a reduction in brain and head size at birth in addition to non-progressive intellectual disability. MCPH is genetically heterogeneous, and 16 loci are known to be associated with loss-of-function mutations predominantly affecting centrosomal-associated proteins, but the multiple roles of centrosomes in cellular function has left questions about etiology. Here, we identified three families affected by homozygous missense mutations in CIT, encoding citron rho-interacting kinase (CIT), which has established roles in cytokinesis. All mutations caused substitution of conserved amino acid residues in the kinase domain and impaired kinase activity. Neural progenitors that were differentiated from induced pluripotent stem cells (iPSCs) derived from individuals with these mutations exhibited abnormal cytokinesis with delayed mitosis, multipolar spindles, and increased apoptosis, rescued by CRISPR/Cas9 genome editing. Our results highlight the importance of cytokinesis in the pathology of primary microcephaly.

}, keywords = {Alleles, Apoptosis, Centrosome, Child, Child, Preschool, Cytokinesis, Female, Genes, Recessive, Humans, Infant, Newborn, Intracellular Signaling Peptides and Proteins, Male, Microcephaly, Mitosis, Mutation, Missense, Pedigree, Protein Serine-Threonine Kinases}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.07.004}, author = {Li, Hongda and Bielas, Stephanie L and Zaki, Maha S and Ismail, Samira and Farfara, Dorit and Um, Kyongmi and Rosti, Rasim O and Scott, Eric C and Tu, Shu and Chi, Neil C and Gabriel, Stacey and Erson-Omay, Emine Z and Ercan-Sencicek, A Gulhan and Yasuno, Katsuhito and {\c C}a{\u g}layan, Ahmet Okay and Kaymak{\c c}alan, Hande and Ekici, Bar{\i}{\c s} and Bilguvar, Kaya and G{\"u}nel, Murat and Gleeson, Joseph G} } @article {23, title = {Mutations in MBOAT7, Encoding Lysophosphatidylinositol Acyltransferase I, Lead to Intellectual Disability Accompanied by Epilepsy and Autistic Features.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Oct 06}, pages = {912-916}, abstract = {

The risk of epilepsy among individuals with intellectual disability (ID) is approximately ten times that of the general population. From a cohort of >5,000 families affected by neurodevelopmental disorders, we identified six consanguineous families harboring homozygous inactivating variants in MBOAT7, encoding lysophosphatidylinositol acyltransferase (LPIAT1). Subjects presented with ID frequently accompanied by epilepsy and autistic features. LPIAT1 is a membrane-bound phospholipid-remodeling enzyme that transfers arachidonic acid (AA) to lysophosphatidylinositol to produce AA-containing phosphatidylinositol. This study suggests a role for AA-containing phosphatidylinositols in the development of ID accompanied by epilepsy and autistic features.

}, keywords = {Acyltransferases, Arachidonic Acid, Autistic Disorder, Child, Child, Preschool, Consanguinity, Epilepsy, Female, Homozygote, Humans, Infant, Intellectual Disability, Lysophospholipids, Male, Membrane Proteins, Mutation, Pedigree, Phosphatidylinositols}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.07.019}, author = {Johansen, Anide and Rosti, Rasim O and Musaev, Damir and Sticca, Evan and Harripaul, Ricardo and Zaki, Maha and {\c C}a{\u g}layan, Ahmet Okay and Azam, Matloob and Sultan, Tipu and Froukh, Tawfiq and Reis, Andr{\'e} and Popp, Bernt and Ahmed, Iltaf and John, Peter and Ayub, Muhammad and Ben-Omran, Tawfeg and Vincent, John B and Gleeson, Joseph G and Abou Jamra, Rami} } @article {159, title = {Functional genome-wide siRNA screen identifies KIAA0586 as mutated in Joubert syndrome.}, journal = {Elife}, volume = {4}, year = {2015}, month = {2015 May 30}, pages = {e06602}, abstract = {

Defective primary ciliogenesis or cilium stability forms the basis of human ciliopathies, including Joubert syndrome (JS), with defective cerebellar vermis development. We performed a high-content genome-wide small interfering RNA (siRNA) screen to identify genes regulating ciliogenesis as candidates for JS. We analyzed results with a supervised-learning approach, using SYSCILIA gold standard, Cildb3.0, a centriole siRNA screen and the GTex project, identifying 591 likely candidates. Intersection of this data with whole exome results from 145 individuals with unexplained JS identified six families with predominantly compound heterozygous mutations in KIAA0586. A c.428del base deletion in 0.1\% of the general population was found in trans with a second mutation in an additional set of 9 of 163 unexplained JS patients. KIAA0586 is an orthologue of chick Talpid3, required for ciliogenesis and Sonic hedgehog signaling. Our results uncover a relatively high frequency cause for JS and contribute a list of candidates for future gene discoveries in ciliopathies.

}, keywords = {Abnormalities, Multiple, Cell Cycle Proteins, Cerebellum, Eye Abnormalities, Gene Frequency, Genetic Predisposition to Disease, Genetic Testing, Genome-Wide Association Study, Heterozygote, Humans, Kidney Diseases, Cystic, Mutant Proteins, Retina, RNA, Small Interfering}, issn = {2050-084X}, doi = {10.7554/eLife.06602}, author = {Roosing, Susanne and Hofree, Matan and Kim, Sehyun and Scott, Eric and Copeland, Brett and Romani, Marta and Silhavy, Jennifer L and Rosti, Rasim O and Schroth, Jana and Mazza, Tommaso and Miccinilli, Elide and Zaki, Maha S and Swoboda, Kathryn J and Milisa-Drautz, Joanne and Dobyns, William B and Mikati, Mohamed A and {\.I}ncecik, Faruk and Azam, Matloob and Borgatti, Renato and Romaniello, Romina and Boustany, Rose-Mary and Clericuzio, Carol L and D{\textquoteright}Arrigo, Stefano and Str{\o}mme, Petter and Boltshauser, Eugen and Stanzial, Franco and Mirabelli-Badenier, Marisol and Moroni, Isabella and Bertini, Enrico and Emma, Francesco and Steinlin, Maja and Hildebrandt, Friedhelm and Johnson, Colin A and Freilinger, Michael and Vaux, Keith K and Gabriel, Stacey B and Aza-Blanc, Pedro and Heynen-Genel, Susanne and Ideker, Trey and Dynlacht, Brian D and Lee, Ji Eun and Valente, Enza Maria and Kim, Joon and Gleeson, Joseph G} } @article {268, title = {Exome sequencing links corticospinal motor neuron disease to common neurodegenerative disorders.}, journal = {Science}, volume = {343}, year = {2014}, month = {2014 Jan 31}, pages = {506-511}, abstract = {

Hereditary spastic paraplegias (HSPs) are neurodegenerative motor neuron diseases characterized by progressive age-dependent loss of corticospinal motor tract function. Although the genetic basis is partly understood, only a fraction of cases can receive a genetic diagnosis, and a global view of HSP is lacking. By using whole-exome sequencing in combination with network analysis, we identified 18 previously unknown putative HSP genes and validated nearly all of these genes functionally or genetically. The pathways highlighted by these mutations link HSP to cellular transport, nucleotide metabolism, and synapse and axon development. Network analysis revealed a host of further candidate genes, of which three were mutated in our cohort. Our analysis links HSP to other neurodegenerative disorders and can facilitate gene discovery and mechanistic understanding of disease.

}, keywords = {Animals, Axons, Biological Transport, Cohort Studies, Exome, Gene Regulatory Networks, Genetic Association Studies, Humans, Motor Neuron Disease, Mutation, Neurons, Nucleotides, Pyramidal Tracts, Sequence Analysis, DNA, Spastic Paraplegia, Hereditary, Synapses, Transcriptome, Zebrafish}, issn = {1095-9203}, doi = {10.1126/science.1247363}, author = {Novarino, Gaia and Fenstermaker, Ali G and Zaki, Maha S and Hofree, Matan and Silhavy, Jennifer L and Heiberg, Andrew D and Abdellateef, Mostafa and Rosti, Basak and Scott, Eric and Mansour, Lobna and Masri, Amira and Kayserili, H{\"u}lya and Al-Aama, Jumana Y and Abdel-Salam, Ghada M H and Karminejad, Ariana and Kara, Majdi and Kara, Bulent and Bozorgmehri, Bita and Ben-Omran, Tawfeg and Mojahedi, Faezeh and El Din Mahmoud, Iman Gamal and Bouslam, Naima and Bouhouche, Ahmed and Benomar, Ali and Hanein, Sylvain and Raymond, Laure and Forlani, Sylvie and Mascaro, Massimo and Selim, Laila and Shehata, Nabil and Al-Allawi, Nasir and Bindu, P S and Azam, Matloob and G{\"u}nel, Murat and Caglayan, Ahmet and Bilguvar, Kaya and Tolun, Aslihan and Issa, Mahmoud Y and Schroth, Jana and Spencer, Emily G and Rosti, Rasim O and Akizu, Naiara and Vaux, Keith K and Johansen, Anide and Koh, Alice A and Megahed, Hisham and Durr, Alexandra and Brice, Alexis and Stevanin, Giovanni and Gabriel, Stacy B and Ideker, Trey and Gleeson, Joseph G} } @article {203, title = {Mutations in KATNB1 cause complex cerebral malformations by disrupting asymmetrically dividing neural progenitors.}, journal = {Neuron}, volume = {84}, year = {2014}, month = {2014 Dec 17}, pages = {1226-39}, abstract = {

Exome sequencing analysis of over 2,000 children with complex malformations of cortical development identified five independent (four homozygous and one compound heterozygous) deleterious mutations in KATNB1, encoding the regulatory subunit of the microtubule-severing enzyme Katanin. Mitotic spindle formation is defective in patient-derived fibroblasts, a consequence of disrupted interactions of mutant KATNB1 with KATNA1, the catalytic subunit of Katanin, and other microtubule-associated proteins. Loss of KATNB1 orthologs in zebrafish (katnb1) and flies (kat80) results in microcephaly, recapitulating the human phenotype. In the developing Drosophila optic lobe, kat80 loss specifically affects the asymmetrically dividing neuroblasts, which display supernumerary centrosomes and spindle abnormalities during mitosis, leading to cell cycle progression delays and reduced cell numbers. Furthermore, kat80 depletion results in dendritic arborization defects in sensory and motor neurons, affecting neural architecture. Taken together, we provide insight into the mechanisms by which KATNB1 mutations cause human cerebral cortical malformations, demonstrating its fundamental role during brain development.

}, keywords = {Adenosine Triphosphatases, Animals, Brain, Cell Count, Cell Division, Dendrites, Drosophila, Drosophila Proteins, Humans, Katanin, Mice, Microcephaly, Microtubule-Associated Proteins, Mutation, Neural Stem Cells, Neurogenesis, Optic Lobe, Nonmammalian, Spindle Apparatus, Zebrafish}, issn = {1097-4199}, doi = {10.1016/j.neuron.2014.12.014}, author = {Mishra-Gorur, Ketu and {\c C}a{\u g}layan, Ahmet Okay and Schaffer, Ashleigh E and Chabu, Chiswili and Henegariu, Octavian and Vonhoff, Fernando and Akg{\"u}m{\"u}{\c s}, G{\"o}zde Tu{\u g}ce and Nishimura, Sayoko and Han, Wenqi and Tu, Shu and Baran, Bur{\c c}in and G{\"u}m{\"u}{\c s}, Hakan and Dilber, Cengiz and Zaki, Maha S and Hossni, Heba A A and Rivi{\`e}re, Jean-Baptiste and Kayserili, H{\"u}lya and Spencer, Emily G and Rosti, Rasim O and Schroth, Jana and Per, H{\"u}seyin and Caglar, Caner and {\c C}a{\u g}lar, {\c C}a{\u g}ri and D{\"o}len, Duygu and Baranoski, Jacob F and Kumanda{\c s}, Sefer and Minja, Frank J and Erson-Omay, E Zeynep and Mane, Shrikant M and Lifton, Richard P and Xu, Tian and Keshishian, Haig and Dobyns, William B and Chi, Neil C and {\v S}estan, Nenad and Louvi, Angeliki and Bilguvar, Kaya and Yasuno, Katsuhito and Gleeson, Joseph G and G{\"u}nel, Murat} }