@article {818, title = {HEM1 deficiency disrupts mTORC2 and F-actin control in inherited immunodysregulatory disease.}, journal = {Science}, volume = {369}, year = {2020}, month = {2020 07 10}, pages = {202-207}, abstract = {

Immunodeficiency often coincides with hyperactive immune disorders such as autoimmunity, lymphoproliferation, or atopy, but this coincidence is rarely understood on a molecular level. We describe five patients from four families with immunodeficiency coupled with atopy, lymphoproliferation, and cytokine overproduction harboring mutations in , which encodes the hematopoietic-specific HEM1 protein. These mutations cause the loss of the HEM1 protein and the WAVE regulatory complex (WRC) or disrupt binding to the WRC regulator, Arf1, thereby impairing actin polymerization, synapse formation, and immune cell migration. Diminished cortical actin networks caused by WRC loss led to uncontrolled cytokine release and immune hyperresponsiveness. HEM1 loss also blocked mechanistic target of rapamycin complex 2 (mTORC2)-dependent AKT phosphorylation, T cell proliferation, and selected effector functions, leading to immunodeficiency. Thus, the evolutionarily conserved HEM1 protein simultaneously regulates filamentous actin (F-actin) and mTORC2 signaling to achieve equipoise in immune responses.

}, keywords = {Actins, ADP-Ribosylation Factor 1, CD4-Positive T-Lymphocytes, Cell Proliferation, Cytokines, Humans, Immunologic Deficiency Syndromes, Lymphoproliferative Disorders, Mechanistic Target of Rapamycin Complex 2, Membrane Proteins, Pedigree, Phosphorylation, Wiskott-Aldrich Syndrome Protein Family}, issn = {1095-9203}, doi = {10.1126/science.aay5663}, author = {Cook, Sarah A and Comrie, William A and Poli, M Cecilia and Similuk, Morgan and Oler, Andrew J and Faruqi, Aiman J and Kuhns, Douglas B and Yang, Sheng and Vargas-Hernandez, Alexander and Carisey, Alexandre F and Fournier, Benjamin and Anderson, D Eric and Price, Susan and Smelkinson, Margery and Abou Chahla, Wadih and Forbes, Lisa R and Mace, Emily M and Cao, Tram N and Coban-Akdemir, Zeynep H and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Lupski, James R and Orange, Jordan S and Cuvelier, Geoffrey D E and Al Hassani, Moza and Al Kaabi, Nawal and Al Yafei, Zain and Jyonouchi, Soma and Raje, Nikita and Caldwell, Jason W and Huang, Yanping and Burkhardt, Janis K and Latour, Sylvain and Chen, Baoyu and ElGhazali, Gehad and Rao, V Koneti and Chinn, Ivan K and Lenardo, Michael J} } @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 {746, title = {Regulation of human cerebral cortical development by EXOC7 and EXOC8, components of the exocyst complex, and roles in neural progenitor cell proliferation and survival.}, journal = {Genet Med}, volume = {22}, year = {2020}, month = {2020 06}, pages = {1040-1050}, abstract = {

PURPOSE: The exocyst complex is a conserved protein complex that mediates fusion of intracellular vesicles to the plasma membrane and is implicated in processes including cell polarity, cell migration, ciliogenesis, cytokinesis, autophagy, and fusion of secretory vesicles. The essential role of these genes in human genetic disorders, however, is unknown.

METHODS: We performed homozygosity mapping and exome sequencing of consanguineous families with recessively inherited brain development disorders. We modeled an EXOC7 splice variant in vitro and examined EXOC7 messenger RNA (mRNA) expression in developing mouse and human cortex. We modeled exoc7 loss-of-function in a zebrafish knockout.

RESULTS: We report variants in exocyst complex members, EXOC7 and EXOC8, in a novel disorder of cerebral cortex development. In EXOC7, we identified four independent partial loss-of-function (LOF) variants in a recessively inherited disorder characterized by brain atrophy, seizures, and developmental delay, and in severe cases, microcephaly and infantile death. In EXOC8, we found a homozygous truncating variant in a family with a similar clinical disorder. We modeled exoc7 deficiency in zebrafish and found the absence of exoc7 causes microcephaly.

CONCLUSION: Our results highlight the essential role of the exocyst pathway in normal cortical development and how its perturbation causes complex brain disorders.

}, keywords = {Animals, Brain Diseases, Cell Proliferation, Homozygote, Humans, Mice, Microcephaly, Zebrafish}, issn = {1530-0366}, doi = {10.1038/s41436-020-0758-9}, author = {Coulter, Michael E and Musaev, Damir and DeGennaro, Ellen M and Zhang, Xiaochang and Henke, Katrin and James, Kiely N and Smith, Richard S and Hill, R Sean and Partlow, Jennifer N and Kamumbu, A Stacy and Hatem, Nicole and Barkovich, A James and Aziza, Jacqueline and Chassaing, Nicolas and Zaki, MAH S and Sultan, Tipu and Burglen, Lydie and Rajab, Anna and Al-Gazali, Lihadh and Mochida, Ganeshwaran H and Harris, Matthew P and Gleeson, Joseph G and Walsh, Christopher A} } @article {537, title = {Disruptions in asymmetric centrosome inheritance and WDR62-Aurora kinase B interactions in primary microcephaly.}, journal = {Sci Rep}, volume = {7}, year = {2017}, month = {2017 03 08}, pages = {43708}, abstract = {

Recessive mutations in WD repeat domain 62 (WDR62) cause microcephaly and a wide spectrum of severe brain malformations. Disruption of the mouse ortholog results in microcephaly underlain by reduced proliferation of neocortical progenitors during late neurogenesis, abnormalities in asymmetric centrosome inheritance leading to neuronal migration delays, and altered neuronal differentiation. Spindle pole localization of WDR62 and mitotic progression are defective in patient-derived fibroblasts, which, similar to mouse neocortical progenitors, transiently arrest at prometaphase. Expression of WDR62 is closely correlated with components of the chromosome passenger complex (CPC), a key regulator of mitosis. Wild type WDR62, but not disease-associated mutant forms, interacts with the CPC core enzyme Aurora kinase B and staining of CPC components at centromeres is altered in patient-derived fibroblasts. Our findings demonstrate critical and diverse functions of WDR62 in neocortical development and provide insight into the mechanisms by which its disruption leads to a plethora of structural abnormalities.

}, keywords = {Animals, Aurora Kinase B, Brain, Cell Cycle, Cell Differentiation, Cell Proliferation, Centrosome, Consanguinity, Disease Models, Animal, Epistasis, Genetic, Fluorescent Antibody Technique, Gene Expression, Humans, Inheritance Patterns, Male, Mice, Mice, Knockout, Microcephaly, Mutation, Nerve Tissue Proteins, Neural Stem Cells, Pedigree, Whole Genome Sequencing}, issn = {2045-2322}, doi = {10.1038/srep43708}, author = {Sgourdou, Paraskevi and Mishra-Gorur, Ketu and Saotome, Ichiko and Henagariu, Octavian and Tuysuz, Beyhan and Campos, Cynthia and Ishigame, Keiko and Giannikou, Krinio and Quon, Jennifer L and {\v S}estan, Nenad and {\c C}a{\u g}layan, Ahmet O and G{\"u}nel, Murat and Louvi, Angeliki} } @article {84, title = {Mutations in nuclear pore genes NUP93, NUP205 and XPO5 cause steroid-resistant nephrotic syndrome.}, journal = {Nat Genet}, volume = {48}, year = {2016}, month = {2016 Apr}, pages = {457-65}, abstract = {

Nucleoporins are essential components of the nuclear pore complex (NPC). Only a few diseases have been attributed to NPC dysfunction. Steroid-resistant nephrotic syndrome (SRNS), a frequent cause of chronic kidney disease, is caused by dysfunction of glomerular podocytes. Here we identify in eight families with SRNS mutations in NUP93, its interaction partner NUP205 or XPO5 (encoding exportin 5) as hitherto unrecognized monogenic causes of SRNS. NUP93 mutations caused disrupted NPC assembly. NUP93 knockdown reduced the presence of NUP205 in the NPC, and, reciprocally, a NUP205 alteration abrogated NUP93 interaction. We demonstrate that NUP93 and exportin 5 interact with the signaling protein SMAD4 and that NUP93 mutations abrogated interaction with SMAD4. Notably, NUP93 mutations interfered with BMP7-induced SMAD transcriptional reporter activity. We hereby demonstrate that mutations of NUP genes cause a distinct renal disease and identify aberrant SMAD signaling as a new disease mechanism of SRNS, opening a potential new avenue for treatment.

}, keywords = {Age of Onset, Amino Acid Sequence, Animals, Cell Movement, Cell Proliferation, Cells, Cultured, Child, Child, Preschool, Drug Resistance, Female, Genes, Recessive, Genetic Association Studies, Genetic Linkage, HEK293 Cells, Humans, Infant, Karyopherins, Male, Mice, Molecular Sequence Data, Mutation, Nephrotic Syndrome, Nuclear Pore Complex Proteins, Oxidative Stress, Podocytes, Sequence Analysis, DNA, Steroids, Xenopus laevis}, issn = {1546-1718}, doi = {10.1038/ng.3512}, author = {Braun, Daniela A and Sadowski, Carolin E and Kohl, Stefan and Lovric, Svjetlana and Astrinidis, Susanne A and Pabst, Werner L and Gee, Heon Yung and Ashraf, Shazia and Lawson, Jennifer A and Shril, Shirlee and Airik, Merlin and Tan, Weizhen and Schapiro, David and Rao, Jia and Choi, Won-Il and Hermle, Tobias and Kemper, Markus J and Pohl, Martin and Ozaltin, Fatih and Konrad, Martin and Bogdanovic, Radovan and B{\"u}scher, Rainer and Helmchen, Udo and Serdaroglu, Erkin and Lifton, Richard P and Antonin, Wolfram and Hildebrandt, Friedhelm} } @article {190, title = {Somatic Activating RAS Mutations Cause Vascular Tumors Including Pyogenic Granuloma.}, journal = {J Invest Dermatol}, volume = {135}, year = {2015}, month = {2015 Jun}, pages = {1698-1700}, keywords = {Adolescent, Cell Proliferation, Child, Child, Preschool, Female, Gene Expression Regulation, Neoplastic, Granuloma, Pyogenic, Humans, Infant, Infant, Newborn, Male, Mutation, ras Proteins, Vascular Neoplasms}, issn = {1523-1747}, doi = {10.1038/jid.2015.55}, author = {Lim, Young H and Douglas, Stephanie R and Ko, Christine J and Antaya, Richard J and McNiff, Jennifer M and Zhou, Jing and Choate, Keith A and Narayan, Deepak} } @article {255, title = {Recurrent activating mutation in PRKACA in cortisol-producing adrenal tumors.}, journal = {Nat Genet}, volume = {46}, year = {2014}, month = {2014 Jun}, pages = {613-7}, abstract = {

Adrenal tumors autonomously producing cortisol cause Cushing{\textquoteright}s syndrome. We performed exome sequencing of 25 tumor-normal pairs and identified 2 subgroups. Eight tumors (including three carcinomas) had many somatic copy number variants (CNVs) with frequent deletion of CDC42 and CDKN2A, amplification of 5q31.2 and protein-altering mutations in TP53 and RB1. Seventeen tumors (all adenomas) had no somatic CNVs or TP53 or RB1 mutations. Six of these had known gain-of-function mutations in CTNNB1 (β-catenin) or GNAS (Gαs). Six others had somatic mutations in PRKACA (protein kinase A (PKA) catalytic subunit) resulting in a p.Leu206Arg substitution. Further sequencing identified this mutation in 13 of 63 tumors (35\% of adenomas with overt Cushing{\textquoteright}s syndrome). PRKACA, GNAS and CTNNB1 mutations were mutually exclusive. Leu206 directly interacts with the regulatory subunit of PKA, PRKAR1A. Leu206Arg PRKACA loses PRKAR1A binding, increasing the phosphorylation of downstream targets. PKA activity induces cortisol production and cell proliferation, providing a mechanism for tumor development. These findings define distinct mechanisms underlying adrenal cortisol-producing tumors.

}, keywords = {Adolescent, Adrenal Gland Neoplasms, Adult, Aged, Amino Acid Sequence, Base Sequence, cdc42 GTP-Binding Protein, Cell Proliferation, Cyclic AMP-Dependent Protein Kinase Catalytic Subunits, Cyclin-Dependent Kinase Inhibitor p16, DNA Copy Number Variations, Exome, Female, Gene Deletion, Gene Dosage, HEK293 Cells, Humans, Hydrocortisone, Male, Middle Aged, Molecular Sequence Data, Mutation, Phosphorylation, Sequence Analysis, DNA, Sequence Homology, Amino Acid}, issn = {1546-1718}, doi = {10.1038/ng.2956}, author = {Goh, Gerald and Scholl, Ute I and Healy, James M and Choi, Murim and Prasad, Manju L and Nelson-Williams, Carol and Kunstman, John W and Kuntsman, John W and Korah, Reju and Suttorp, Anna-Carinna and Dietrich, Dimo and Haase, Matthias and Willenberg, Holger S and St{\r a}lberg, Peter and Hellman, Per and Akerstr{\"o}m, G{\"o}ran and Bj{\"o}rklund, Peyman and Carling, Tobias and Lifton, Richard P} }