@article {930, title = {Posterior Neocortex-Specific Regulation of Neuronal Migration by CEP85L Identifies Maternal Centriole-Dependent Activation of CDK5.}, journal = {Neuron}, volume = {106}, year = {2020}, month = {2020 04 22}, pages = {246-255.e6}, abstract = {

Genes mutated in human neuronal migration disorders encode tubulin proteins and a variety of tubulin-binding and -regulating proteins, but it is very poorly understood how these proteins function together to coordinate migration. Additionally, the way in which regional differences in neocortical migration are controlled is completely unknown. Here we describe a new syndrome with remarkably region-specific effects on neuronal migration in the posterior cortex, reflecting de novo variants in CEP85L. We show that CEP85L is required cell autonomously in~vivo and in~vitro for migration, that it localizes to the maternal centriole, and that it forms a complex with many other proteins required for migration, including CDK5, LIS1, NDE1, KIF2A, and DYNC1H1. Loss of CEP85L disrupts CDK5 localization and activation, leading to centrosome disorganization and disrupted microtubule cytoskeleton organization. Together, our findings suggest that CEP85L highlights a complex that controls CDK5 activity to promote neuronal migration.

}, keywords = {Cell Movement, Centrioles, Child, Child, Preschool, Cyclin-Dependent Kinase 5, Cytoskeletal Proteins, Female, Humans, Lissencephaly, Male, Microtubules, Neocortex, Nerve Tissue Proteins, Neurons, Oncogene Proteins, Fusion, Young Adult}, issn = {1097-4199}, doi = {10.1016/j.neuron.2020.01.030}, author = {Kodani, Andrew and Kenny, Connor and Lai, Abbe and Gonzalez, Dilenny M and Stronge, Edward and Sejourne, Gabrielle M and Isacco, Laura and Partlow, Jennifer N and O{\textquoteright}Donnell, Anne and McWalter, Kirsty and Byrne, Alicia B and Barkovich, A James and Yang, Edward and Hill, R Sean and Gawlinski, Pawel and Wiszniewski, Wojciech and Cohen, Julie S and Fatemi, S Ali and Baranano, Kristin W and Sahin, Mustafa and Vossler, David G and Yuskaitis, Christopher J and Walsh, Christopher A} } @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} }