@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 {410, title = {Impaired Amino Acid Transport at the Blood Brain Barrier Is a Cause of Autism Spectrum Disorder.}, journal = {Cell}, volume = {167}, year = {2016}, month = {2016 Dec 01}, pages = {1481-1494.e18}, abstract = {

Autism spectrum disorders (ASD) are a group of genetic disorders often overlapping with other neurological conditions. We previously described abnormalities in the branched-chain amino acid (BCAA) catabolic pathway as a cause of ASD. Here, we show that the solute carrier transporter 7a5 (SLC7A5), a large neutral amino acid transporter localized at the blood brain barrier (BBB), has an essential role in maintaining normal levels of brain BCAAs. In mice, deletion of Slc7a5 from the endothelial cells of the BBB leads to atypical brain amino acid profile, abnormal mRNA translation, and severe neurological abnormalities. Furthermore, we identified several patients with autistic traits and motor delay carrying deleterious homozygous mutations in the SLC7A5 gene. Finally, we demonstrate that BCAA intracerebroventricular administration ameliorates abnormal behaviors in adult mutant mice. Our data elucidate a neurological syndrome defined by SLC7A5 mutations and support an essential role for the BCAA in human brain function.

}, keywords = {Amino Acids, Animals, Autism Spectrum Disorder, Blood-Brain Barrier, Brain, Female, Humans, Infant, Infant, Newborn, Large Neutral Amino Acid-Transporter 1, Male, Mice, Mice, Knockout, Mutation, Pedigree, Protein Biosynthesis, Receptor, TIE-2}, issn = {1097-4172}, doi = {10.1016/j.cell.2016.11.013}, author = {T{\u a}rlungeanu, Dora C and Deliu, Elena and Dotter, Christoph P and Kara, Majdi and Janiesch, Philipp Christoph and Scalise, Mariafrancesca and Galluccio, Michele and Tesulov, Mateja and Morelli, Emanuela and Sonmez, Fatma Mujgan and Bilguvar, Kaya and Ohgaki, Ryuichi and Kanai, Yoshikatsu and Johansen, Anide and Esharif, Seham and Ben-Omran, Tawfeg and Topcu, Meral and Schlessinger, Avner and Indiveri, Cesare and Duncan, Kent E and {\c C}a{\u g}layan, Ahmet Okay and G{\"u}nel, Murat and Gleeson, Joseph G and Novarino, Gaia} } @article {161, title = {Inactivating mutations in MFSD2A, required for omega-3 fatty acid transport in brain, cause a lethal microcephaly syndrome.}, journal = {Nat Genet}, volume = {47}, year = {2015}, month = {2015 Jul}, pages = {809-13}, abstract = {

Docosahexanoic acid (DHA) is the most abundant omega-3 fatty acid in brain, and, although it is considered essential, deficiency has not been linked to disease. Despite the large mass of DHA in phospholipids, the brain does not synthesize it. DHA is imported across the blood-brain barrier (BBB) through the major facilitator superfamily domain-containing 2a (MFSD2A) protein. MFSD2A transports DHA as well as other fatty acids in the form of lysophosphatidylcholine (LPC). We identify two families displaying MFSD2A mutations in conserved residues. Affected individuals exhibited a lethal microcephaly syndrome linked to inadequate uptake of LPC lipids. The MFSD2A mutations impaired transport activity in a cell-based assay. Moreover, when expressed in mfsd2aa-morphant zebrafish, mutants failed to rescue microcephaly, BBB breakdown and lethality. Our results establish a link between transport of DHA and LPCs by MFSD2A and human brain growth and function, presenting the first evidence of monogenic disease related to transport of DHA in humans.

}, keywords = {Adolescent, Animals, Biological Transport, Blood-Brain Barrier, Brain, Case-Control Studies, Child, Child, Preschool, Consanguinity, Fatty Acids, Omega-3, Female, Genes, Lethal, Genetic Association Studies, HEK293 Cells, Humans, Infant, Male, Mice, Knockout, Microcephaly, Mutation, Missense, Syndrome, Tumor Suppressor Proteins, Zebrafish}, issn = {1546-1718}, doi = {10.1038/ng.3311}, author = {Guemez-Gamboa, Alicia and Nguyen, Long N and Yang, Hongbo and Zaki, Maha S and Kara, Majdi and Ben-Omran, Tawfeg and Akizu, Naiara and Rosti, Rasim Ozgur and Rosti, Basak and Scott, Eric and Schroth, Jana and Copeland, Brett and Vaux, Keith K and Cazenave-Gassiot, Amaury and Quek, Debra Q Y and Wong, Bernice H and Tan, Bryan C and Wenk, Markus R and G{\"u}nel, Murat and Gabriel, Stacey and Chi, Neil C and Silver, David L 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 {278, title = {Mutations in CSPP1 lead to classical Joubert syndrome.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 Jan 02}, pages = {80-6}, abstract = {

Joubert syndrome and related disorders (JSRDs) are genetically heterogeneous and characterized by a distinctive mid-hindbrain malformation. Causative mutations lead to primary cilia dysfunction, which often results in variable involvement of other organs such as the liver, retina, and kidney. We identified predicted null mutations in CSPP1 in six individuals affected by classical JSRDs. CSPP1 encodes a protein localized to centrosomes and spindle poles, as well as to the primary cilium. Despite the known interaction between CSPP1 and nephronophthisis-associated proteins, none of the affected individuals in our cohort presented with kidney disease, and further, screening of a large cohort of individuals with nephronophthisis demonstrated no mutations. CSPP1 is broadly expressed in neural tissue, and its encoded protein localizes to the primary cilium in an in~vitro model of human neurogenesis. Here, we show abrogated protein levels and ciliogenesis in affected fibroblasts. Our data thus suggest that CSPP1 is involved in neural-specific functions of primary cilia.

}, keywords = {Abnormalities, Multiple, Brain, Cell Cycle Proteins, Centrosome, Cerebellar Diseases, Cerebellum, Cilia, Cohort Studies, Eye Abnormalities, Fibroblasts, Gene Deletion, Humans, Image Processing, Computer-Assisted, Kidney Diseases, Cystic, Microtubule-Associated Proteins, Polymorphism, Single Nucleotide, Retina}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.11.015}, author = {Akizu, Naiara and Silhavy, Jennifer L and Rosti, Rasim Ozgur and Scott, Eric and Fenstermaker, Ali G and Schroth, Jana and Zaki, Maha S and Sanchez, Henry and Gupta, Neerja and Kabra, Madhulika and Kara, Majdi and Ben-Omran, Tawfeg and Rosti, Basak and Guemez-Gamboa, Alicia and Spencer, Emily and Pan, Roger and Cai, Na and Abdellateef, Mostafa and Gabriel, Stacey and Halbritter, Jan and Hildebrandt, Friedhelm and van Bokhoven, Hans and G{\"u}nel, Murat and Gleeson, Joseph G} }