Biallelic mutations in nucleoporin NUP88 cause lethal fetal akinesia deformation sequence

• Published in: PLoS genetics Vol. 14; no. 12; p. e1007845
• Main Authors: Bonnin, Edith, Cabochette, Pauline, Filosa, Alessandro, Jühlen, Ramona, Komatsuzaki, Shoko, Hezwani, Mohammed, Dickmanns, Achim, Martinelli, Valérie, Vermeersch, Marjorie, Supply, Lynn, Martins, Nuno, Pirenne, Laurence, Ravenscroft, Gianina, Lombard, Marcus, Port, Sarah, Spillner, Christiane, Janssens, Sandra, Roets, Ellen, Van Dorpe, Jo, Lammens, Martin, Kehlenbach, Ralph H, Ficner, Ralf, Laing, Nigel G, Hoffmann, Katrin, Vanhollebeke, Benoit, Fahrenkrog, Birthe
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 13.12.2018; Public Library of Science (PLoS)
• Subjects: Akinesia; Alleles; Amino Acid Sequence; Animals; Animals, Genetically Modified; Arthrogryposis - embryology; Arthrogryposis - genetics; Arthrogryposis - physiopathology; Bioinformatics; Biology and Life Sciences; Congenital defects; Consanguinity; Danio rerio; Developmental disabilities; Developmental stages; Disease Models, Animal; Female; Fetal movements; Fetuses; Funding; Gene expression; Gene mutation; Genes, Lethal; Humans; Immunohistochemistry; Laboratories; Male; Medical research; Medicine; Medicine and Health Sciences; Mice; Models, Molecular; Molecular biology; Muscle Proteins - metabolism; Mutation; Neurodegenerative diseases; Neuromuscular Junction - physiopathology; Neuromuscular junctions; Neurosciences; Nuclear Pore Complex Proteins - chemistry; Nuclear Pore Complex Proteins - deficiency; Nuclear Pore Complex Proteins - genetics; Nucleoporins; Pathology; Pedigree; Phenotypes; Pregnancy; Protein Conformation; Proteins; Rapsyn; Receptors, Nicotinic - metabolism; Research and Analysis Methods; Sequence Homology, Amino Acid; Supervision; Zebrafish - abnormalities; Zebrafish - genetics; Zebrafish - physiology; Zebrafish Proteins - deficiency; Zebrafish Proteins - genetics; Belgium; Australia; Western Australia Australia; Germany
• ISSN: 1553-7404; 1553-7390; 1553-7404
• DOI: 10.1371/journal.pgen.1007845

Nucleoporins build the nuclear pore complex (NPC), which, as sole gate for nuclear-cytoplasmic exchange, is of outmost importance for normal cell function. Defects in the process of nucleocytoplasmic transport or in its machinery have been frequently described in human diseases, such as cancer and neurodegenerative disorders, but only in a few cases of developmental disorders. Here we report biallelic mutations in the nucleoporin NUP88 as a novel cause of lethal fetal akinesia deformation sequence (FADS) in two families. FADS comprises a spectrum of clinically and genetically heterogeneous disorders with congenital malformations related to impaired fetal movement. We show that genetic disruption of nup88 in zebrafish results in pleiotropic developmental defects reminiscent of those seen in affected human fetuses, including locomotor defects as well as defects at neuromuscular junctions. Phenotypic alterations become visible at distinct developmental stages, both in affected human fetuses and in zebrafish, whereas early stages of development are apparently normal. The zebrafish phenotypes caused by nup88 deficiency are rescued by expressing wild-type Nup88 but not the disease-linked mutant forms of Nup88. Furthermore, using human and mouse cell lines as well as immunohistochemistry on fetal muscle tissue, we demonstrate that NUP88 depletion affects rapsyn, a key regulator of the muscle nicotinic acetylcholine receptor at the neuromuscular junction. Together, our studies provide the first characterization of NUP88 in vertebrate development, expand our understanding of the molecular events causing FADS, and suggest that variants in NUP88 should be investigated in cases of FADS.