@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 {355, title = {PRUNE is crucial for normal brain development and mutated in microcephaly with neurodevelopmental impairment.}, journal = {Brain}, volume = {140}, year = {2017}, month = {2017 Apr 01}, pages = {940-952}, abstract = {

PRUNE is a member of the DHH (Asp-His-His) phosphoesterase protein superfamily of molecules important for cell motility, and implicated in cancer progression. Here we investigated multiple families from Oman, India, Iran and Italy with individuals affected by a new autosomal recessive neurodevelopmental and degenerative disorder in which the cardinal features include primary microcephaly and profound global developmental delay. Our genetic studies identified biallelic mutations of PRUNE1 as responsible. Our functional assays of disease-associated variant alleles revealed impaired microtubule polymerization, as well as cell migration and proliferation properties, of mutant PRUNE. Additionally, our studies also highlight a potential new role for PRUNE during microtubule polymerization, which is essential for the cytoskeletal rearrangements that occur during cellular division and proliferation. Together these studies define PRUNE as a molecule fundamental for normal human cortical development and define cellular and clinical consequences associated with PRUNE mutation.

}, keywords = {Adolescent, Brain, Carrier Proteins, Cell Differentiation, Cell Movement, Cerebral Cortex, Child, Child, Preschool, Cytoskeleton, Developmental Disabilities, Female, Genes, Recessive, Heredodegenerative Disorders, Nervous System, Humans, Infant, Male, Microcephaly, Microtubules, Mutation, Pedigree, Young Adult}, issn = {1460-2156}, doi = {10.1093/brain/awx014}, author = {Zollo, Massimo and Ahmed, Mustafa and Ferrucci, Veronica and Salpietro, Vincenzo and Asadzadeh, Fatemeh and Carotenuto, Marianeve and Maroofian, Reza and Al-Amri, Ahmed and Singh, Royana and Scognamiglio, Iolanda and Mojarrad, Majid and Musella, Luca and Duilio, Angela and Di Somma, Angela and Karaca, Ender and Rajab, Anna and Al-Khayat, Aisha and Mohan Mohapatra, Tribhuvan and Eslahi, Atieh and Ashrafzadeh, Farah and Rawlins, Lettie E and Prasad, Rajniti and Gupta, Rashmi and Kumari, Preeti and Srivastava, Mona and Cozzolino, Flora and Kumar Rai, Sunil and Monti, Maria and Harlalka, Gaurav V and Simpson, Michael A and Rich, Philip and Al-Salmi, Fatema and Patton, Michael A and Chioza, Barry A and Efthymiou, Stephanie and Granata, Francesca and Di Rosa, Gabriella and Wiethoff, Sarah and Borgione, Eugenia and Scuderi, Carmela and Mankad, Kshitij and Hanna, Michael G and Pucci, Piero and Houlden, Henry and Lupski, James R and Crosby, Andrew H and Baple, Emma L} }