The Experts below are selected from a list of 7788 Experts worldwide ranked by ideXlab platform
Orly Reiner - One of the best experts on this subject based on the ideXlab platform.
-
VERIFYING INTEGRATION IN YOUR FAVORITE GENE
2015Co-Authors: Short Communication, Tamar Sapir, Anna Gorelik, Orly ReinerAbstract:Abbreviations used: β-geo – fusion of β-galactosidase and neomycin transferase; DCLK2 – Doublecortin-like-kinase 2; DCX – doublcortin; DsRed – Discosoma sp. reef coral red fluorescent protein; ES – embryonic stem; HEK293 – human embryonic kidney cell line; IGTC – International Gene Trap Consortium; IP – immunoprecipitation; LacZ – beta galactosidase reporter gene; PCR – polymerase chain reaction; 5’-RACE – Rapid amplification of 5 ’ complementary DNA ends; X-gal – 5-bromo-4-chloro-3-indolyl-β-D-galactosid
-
Use of RNA Interference by In Utero Electroporation to Study Cortical Development: The Example of the Doublecortin Superfamily
Genes, 2012Co-Authors: Orly Reiner, Anna Gorelik, Raanan GreenmanAbstract:The way we study cortical development has undergone a revolution in the last few years following the ability to use shRNA in the developing brain of the rodent embryo. The first gene to be knocked-down in the developing brain was Doublecortin (Dcx). Here we will review knockdown experiments in the developing brain and compare them with knockout experiments, thus highlighting the advantages and disadvantages using the different systems. Our review will focus on experiments relating to the Doublecortin superfamily of proteins.
-
linking cytoplasmic dynein and transport of rab8 vesicles to the midbody during cytokinesis by the Doublecortin domain containing 5 protein
Journal of Cell Science, 2011Co-Authors: Anna Kaplan, Orly ReinerAbstract:Completion of mitosis requires microtubule-dependent transport of membranes to the midbody. Here, we identified a role in cytokinesis for Doublecortin domain-containing protein 5 (DCDC5), a member of the Doublecortin protein superfamily. DCDC5 is a microtubule-associated protein expressed in both specific and dynamic fashions during mitosis. We show that DCDC5 interacts with cytoplasmic dynein and Rab8 (also known as Ras-related protein Rab-8A), as well as with the Rab8 nucleotide exchange factor Rabin8 (also known as Rab-3A-interacting protein). Following DCDC5 knockdown, the durations of the metaphase to anaphase transition and cytokinesis, and the proportion of multinucleated cells increases, whereas cell viability decreases. Furthermore, knockdown of DCDC5 or addition of a dynein inhibitor impairs the entry of Golgi-complex-derived Rab8-positive vesicles to the midbody. These findings suggest that DCDC5 plays an important role in mediating dynein-dependent transport of Rab8-positive vesicles and in coordinating late cytokinesis.
-
Doublecortin supports the development of dendritic arbors in primary hippocampal neurons.
Developmental neuroscience, 2007Co-Authors: Dror Cohen, Menahem Segal, Orly ReinerAbstract:Doublecortin (DCX) is a microtubule-associated protein necessary for neuronal migration. In spite of its ubiquitous distribution in dendrites, its possible role in dendrite development has not yet bee
-
the evolving Doublecortin dcx superfamily
BMC Genomics, 2006Co-Authors: Orly Reiner, Frederic M Coquelle, Irit Orr, Bastian Peter, Anna Kaplan, Talia Levy, Tamar Sapir, Naama Barkai, Gregor EicheleAbstract:Background Doublecortin (DCX) domains serve as protein-interaction platforms. Mutations in members of this protein superfamily are linked to several genetic diseases. Mutations in the human DCX gene result in abnormal neuronal migration, epilepsy, and mental retardation; mutations in RP1 are associated with a form of inherited blindness, and DCDC2 has been associated with dyslectic reading disabilities.
Joseph G Gleeson - One of the best experts on this subject based on the ideXlab platform.
-
Doublecortin-like kinase enhances dendritic remodelling and negatively regulates synapse maturation
Nature communications, 2013Co-Authors: Euikyung Shin, Joseph G Gleeson, Yutaro Kashiwagi, Toshihiko Kuriu, Hirohide Iwasaki, Teruyuki Tanaka, Hiroyuki Koizumi, Shigeo OkabeAbstract:Dendritic morphogenesis and formation of synapses at appropriate dendritic locations are essential for the establishment of proper neuronal connectivity. Recent imaging studies provide evidence for stabilization of dynamic distal branches of dendrites by the addition of new synapses. However, molecules involved in both dendritic growth and suppression of synapse maturation remain to be identified. Here we report two distinct functions of Doublecortin-like kinases, chimeric proteins containing both a microtubule-binding domain and a kinase domain in postmitotic neurons. First, Doublecortin-like kinases localize to the distal dendrites and promote their growth by enhancing microtubule bundling. Second, Doublecortin-like kinases suppress maturation of synapses through multiple pathways, including reduction of PSD-95 by the kinase domain and suppression of spine structural maturation by the microtubule-binding domain. Thus, Doublecortin-like kinases are critical regulators of dendritic development by means of their specific targeting to the distal dendrites, and their local control of dendritic growth and synapse maturation.
-
Mice lacking Doublecortin and Doublecortin-like kinase 2 display altered hippocampal neuronal maturation and spontaneous seizures
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: Geraldine Kerjan, Hiroyuki Koizumi, Edward B. Han, Céline Dubé, Stevan Djakovic, Gentry N. Patrick, Tallie Z. Baram, Stephen F. Heinemann, Joseph G GleesonAbstract:Mutations in Doublecortin (DCX) are associated with intractable epilepsy in humans, due to a severe disorganization of the neocortex and hippocampus known as classical lissencephaly. However, the basis of the epilepsy in lissencephaly remains unclear. To address potential functional redundancy with murin Dcx, we targeted one of the closest homologues, Doublecortin-like kinase 2 (Dclk2). Here, we report that Dcx; Dclk2-null mice display frequent spontaneous seizures that originate in the hippocampus, with most animals dying in the first few months of life. Elevated hippocampal expression of c-fos and loss of somatostatin-positive interneurons were identified, both known to correlate with epilepsy. Dcx and Dclk2 are coexpressed in developing hippocampus, and, in their absence, there is dosage-dependent disrupted hippocampal lamination associated with a cell-autonomous simplification of pyramidal dendritic arborizations leading to reduced inhibitory synaptic tone. These data suggest that hippocampal dysmaturation and insufficient receptive field for inhibitory input may underlie the epilepsy in lissencephaly, and suggest potential therapeutic strategies for controlling epilepsy in these patients.
-
Doublecortin-like kinase Functions with Doublecortin to Mediate Fiber Tract Decussation and Neuronal Migration
Neuron, 2006Co-Authors: Hiroyuki Koizumi, Teruyuki Tanaka, Joseph G GleesonAbstract:The potential role of Doublecortin (Dcx), encoding a microtubule-associated protein, in brain development has remained controversial. Humans with mutations show profound alterations in cortical lamination, whereas in mouse, RNAi-mediated knockdown but not germline knockout shows abnormal positioning of cortical neurons. Here, we report that the Doublecortin-like kinase (Dclk) gene functions in a partially redundant pathway with Dcx in the formation of axonal projections across the midline and migration of cortical neurons. Dosage-dependent genetic effects were observed in both interhemispheric connectivity and migration of cortically and subcortically derived neurons. Surprisingly, RNAi-mediated knockdown of either gene results in similar migration defects. These results indicate the Dcx microtubule-associated protein family is required for proper neuronal migration and axonal wiring.
-
The Doublecortin and Doublecortin-like kinase 1 genes cooperate in murine hippocampal development.
Cerebral cortex (New York N.Y. : 1991), 2006Co-Authors: Teruyuki Tanaka, Hiroyuki Koizumi, Joseph G GleesonAbstract:The Doublecortin (Dcx) and Doublecortin-like kinase 1 (Dclk) genes are developmentally expressed neuronal microtubule-associated proteins. Humans with DCX mutations show a severe defect in hippocampal development, but targeted deletion in mouse shows only a defect in pyramidal neuron lamination. There is significant sequence overlap between Dcx and Dclk, suggesting functional redundancy. Here we show that the two genes display overlapping expression patterns in developing mouse hippocampus. Targeted deletion of Dclk shows no appreciable developmental defect in the hippocampus, but removal of both genes shows severe hippocampal lamination defects involving the entire cornu ammonis and dentate gyrus fields that mimic the human phenotype. These results suggest these genes are partially functionally redundant in the formation of the murine hippocampus.
-
Another double trouble. Silent carriers of Doublecortin mutations.
Neurology, 2003Co-Authors: Joseph G GleesonAbstract:The article “Somatic mosaicism and variable penetrance in Doublecortin -associated migration disorders” by Aigner et al. in this issue of Neurology indicates that many mutations are “silent” in the form of somatic mutations, changing the recommendations for genetic screening and counseling. Mutations in the X-linked gene Doublecortin ( DCX ) are the cause of X-linked lissencephaly in males and X-linked subcortical band heterotopia in females. Because females have two X chromosomes and randomly inactivate one in every cell, females are normally mosaics for two populations of cells. Following random X-inactivation in females with a DCX mutation, approximately half of cells express the mutation, suggesting the hypothesis that mutant cells constitute the heterotopic band in the brain. Recent data support this suggestion.1 Genetic conditions inherited in a dominant fashion, whether X-linked or autosomal, are typically fully penetrant: …
Irmgard Amrein - One of the best experts on this subject based on the ideXlab platform.
-
different regulation of adult hippocampal neurogenesis in western house mice mus musculus domesticus and c57bl 6 mice
Behavioural Brain Research, 2012Co-Authors: Fabienne Klaus, Thomas Hauser, Anna K Lindholm, Heather A Cameron, Lutz Slomianka, Hanspeter Lipp, Irmgard AmreinAbstract:Adult hippocampal neurogenesis (AHN) of laboratory rodents is enhanced by physical exercise in a running wheel. However, little is known about modulation of AHN in wild-living rodent species. The finding that AHN cannot be modulated by voluntary exercise in wild wood mice suggests that AHN may be regulated differently under natural conditions than in laboratory adapted animals. In order to minimize genetic influences, we aimed to investigate the genetically closest wild-living relatives of laboratory mice. Here, C57BL/6 mice and F1 offspring of wild house mice (Mus musculus domesticus) were tested in two different running paradigms: voluntary running and running-for-food - a condition in which mice had to run for their daily allowance of food. In house mice, we found a non-significant trend towards increased numbers of proliferating cells and Doublecortin-positive immature neurons in both voluntary runners and runners-for-food. Voluntary running in C57BL/6 mice resulted in a 30% increase in cell proliferation and a pronounced 70% increase in Doublecortin-positive cells. C57BL/6 runners-for-food ran as much as voluntary runners, but they showed no enhancement of cell proliferation, a small increase in the number of Doublecortin-positive cells and more pyknotic cells compared to controls. Taken together, these findings suggest that motivational aspects of running are critical determinants of the increased cell proliferation in C57BL/6 mice. In contrast, running has smaller and context-independent effects in house mice. The findings imply a difference in the regulation of AHN in C57BL/6 mice and their wild-derived conspecifics.
-
Different regulation of adult hippocampal neurogenesis in Western house mice (Mus musculus domesticus) and C57BL/6 mice.
Behavioural brain research, 2011Co-Authors: Fabienne Klaus, Thomas Hauser, Anna K Lindholm, Heather A Cameron, Lutz Slomianka, Hanspeter Lipp, Irmgard AmreinAbstract:Adult hippocampal neurogenesis (AHN) of laboratory rodents is enhanced by physical exercise in a running wheel. However, little is known about modulation of AHN in wild-living rodent species. The finding that AHN cannot be modulated by voluntary exercise in wild wood mice suggests that AHN may be regulated differently under natural conditions than in laboratory adapted animals. In order to minimize genetic influences, we aimed to investigate the genetically closest wild-living relatives of laboratory mice. Here, C57BL/6 mice and F1 offspring of wild house mice (Mus musculus domesticus) were tested in two different running paradigms: voluntary running and running-for-food - a condition in which mice had to run for their daily allowance of food. In house mice, we found a non-significant trend towards increased numbers of proliferating cells and Doublecortin-positive immature neurons in both voluntary runners and runners-for-food. Voluntary running in C57BL/6 mice resulted in a 30% increase in cell proliferation and a pronounced 70% increase in Doublecortin-positive cells. C57BL/6 runners-for-food ran as much as voluntary runners, but they showed no enhancement of cell proliferation, a small increase in the number of Doublecortin-positive cells and more pyknotic cells compared to controls. Taken together, these findings suggest that motivational aspects of running are critical determinants of the increased cell proliferation in C57BL/6 mice. In contrast, running has smaller and context-independent effects in house mice. The findings imply a difference in the regulation of AHN in C57BL/6 mice and their wild-derived conspecifics.
Jean-michel Bellanger - One of the best experts on this subject based on the ideXlab platform.
-
The Doublecortin-related Gene zyg-8 is a Microtubule Organizer in Caenorhabditis elegans Neurons
Journal of Cell Science, 2012Co-Authors: Jean-michel Bellanger, Juan G. Cueva, Renee Baran, Garland Tang, Miriam B. Goodman, Anne DebantAbstract:Doublecortin-domain containing (DCDC) genes play key roles in the normal and pathological development of the human brain cortex. The origin of the cellular specialisation and the functional redundancy of these microtubule (MT)-associated proteins (MAPs), especially those of Doublecortin (DCX) and Doublecortin-like kinase (DCLKs) genes, is still unclear. The DCX domain has the ability to control MT architecture and bundling. However, the physiological significance of such properties is not fully understood. To address these issues, we sought post-mitotic roles for zyg-8, the sole representative of the DCX-DCLK subfamily of genes in C. elegans. Previously, zyg-8 has been shown to control anaphase-spindle positioning in one-cell stage embryos, but functions of the gene later in development have not been investigated. Here we show that wild-type zyg-8 is required beyond early embryonic divisions for proper development, spontaneous locomotion and touch sensitivity of adult worms. Consistently, we find zyg-8 expression in the six touch receptor neurons (TRNs), as well as in a subset of other neuronal and non-neuronal cells. In TRNs and motoneurons, zyg-8 controls cell body shape/polarity and process outgrowth and morphology. Ultrastructural analysis of mutant animals reveals that zyg-8 promotes structural integrity, length and number of individual MTs, as well as their bundled organisation in TRNs, with no impact on MT architecture.
-
zyg-8, a gene required for spindle positioning in C. elegans, encodes a Doublecortin-related kinase that promotes microtubule assembly.
Developmental cell, 2001Co-Authors: Pierre Gönczy, Jean-michel Bellanger, Matthew Kirkham, Andrei Pozniakowski, Karine Baumer, Jennifer B. Phillips, Anthony A. HymanAbstract:Proper spindle positioning is essential for spatial control of cell division. Here, we show that zyg-8 plays a key role in spindle positioning during asymmetric division of one-cell stage C. elegans embryos by promoting microtubule assembly during anaphase. ZYG-8 harbors a kinase domain and a domain related to Doublecortin, a microtubule-associated protein (MAP) affected in patients with neuronal migration disorders. Sequencing of zyg-8 mutant alleles demonstrates that both domains are essential for function. ZYG-8 binds to microtubules in vitro, colocalizes with microtubules in vivo, and promotes stabilization of microtubules to drug or cold depolymerization in COS-7 cells. Our findings demonstrate that ZYG-8 is a MAP crucial for proper spindle positioning in C. elegans, and indicate that the function of the Doublecortin domain in modulating microtubule dynamics is conserved across metazoan evolution.
Christopher A. Walsh - One of the best experts on this subject based on the ideXlab platform.
-
Molecular Basis for Specific Regulation of Neuronal Kinesin-3 Motors by Doublecortin Family Proteins
Molecular cell, 2012Co-Authors: Judy S. Liu, Christian Schubert, Franck J. Fourniol, Jyoti K. Jaiswal, Anne Houdusse, Collin M. Stultz, Carolyn A. Moores, Christopher A. WalshAbstract:Doublecortin (Dcx) defines a growing family of microtubule (MT)-associated proteins (MAPs) involved in neuronal migration and process outgrowth. We show that Dcx is essential for the function of Kif1a, a kinesin-3 motor protein that traffics synaptic vesicles. Neurons lacking Dcx and/or its structurally conserved paralogue, Doublecortin-like kinase 1 (Dclk1), show impaired Kif1a-mediated transport of Vamp2, a cargo of Kif1a, with decreased run length. Human disease-associated mutations in Dcx's linker sequence (e.g., W146C, K174E) alter Kif1a/Vamp2 transport by disrupting Dcx/Kif1a interactions without affecting Dcx MT binding. Dcx specifically enhances binding of the ADP-bound Kif1a motor domain to MTs. Cryo-electron microscopy and subnanometer-resolution image reconstruction reveal the kinesin-dependent conformational variability of MT-bound Dcx and suggest a model for MAP-motor crosstalk on MTs. Alteration of kinesin run length by MAPs represents a previously undiscovered mode of control of kinesin transport and provides a mechanism for regulation of MT-based transport by local signals.
-
Doublecortin is expressed in articular chondrocytes
Biochemical and Biophysical Research Communications, 2007Co-Authors: James A. Ryan, Paul E. Di Cesare, Christopher A. WalshAbstract:Articular cartilage and cartilage in the embryonic cartilaginous anlagen and growth plates are both hyaline cartilages. In this study, we found that Doublecortin (DCX) was expressed in articular chondrocytes but not in chondrocytes from the cartilaginous anlagen or growth plates. DCX was expressed by the cells in the chondrogenous layers but not intermediate layer of joint interzone. Furthermore, the synovium and cruciate ligaments were DCX-negative. DCX-positive chondrocytes were very rare in tissue engineered cartilage derived from in vitro pellet culture of rat chondrosarcoma, ATDC5, and C3H10T1/2 cells. However, the new hyaline cartilage formed in rabbit knee defect contained mostly DCX-positive chondrocytes. Our results demonstrate that DCX can be used as a marker to distinguish articular chondrocytes from other chondrocytes and to evaluate the quality of tissue engineered or regenerated cartilage in terms of their ‘‘articular’’ or ‘‘non-articular’’ nature.
-
genetic interactions between Doublecortin and Doublecortin like kinase in neuronal migration and axon outgrowth
Neuron, 2006Co-Authors: Thomas A S Deuel, Judy S. Liu, Joseph C Corbo, Seungyun Yoo, Lucy B Rorkeadams, Christopher A. WalshAbstract:Summary Although mutations in the human Doublecortin gene ( DCX ) cause profound defects in cortical neuronal migration, a genetic deletion of Dcx in mice produces a milder defect. A second locus, Doublecortin-like kinase ( Dclk ), encodes a protein with similar "Doublecortin domains" and microtubule stabilization properties that may compensate for Dcx. Here, we generate a mouse with a Dclk mutation that causes no obvious migrational abnormalities but show that mice mutant for both Dcx and Dclk demonstrate perinatal lethality, disorganized neocortical layering, and profound hippocampal cytoarchitectural disorganization. Surprisingly, Dcx −/y ;Dclk − / − mutants have widespread axonal defects, affecting the corpus callosum, anterior commissure, subcortical fiber tracts, and internal capsule. Dcx/Dclk-deficient dissociated neurons show abnormal axon outgrowth and dendritic structure, with defects in axonal transport of synaptic vesicle proteins. Dcx and Dclk may directly or indirectly regulate microtubule-based vesicle transport, a process critical to both neuronal migration and axon outgrowth.
-
the dcx domain tandems of Doublecortin and Doublecortin like kinase
Nature Structural & Molecular Biology, 2003Co-Authors: Myunghee Kim, Daniel Krowarsch, Yuanyi Feng, Yancho Devedjiev, Tomasz Cierpicki, Zbigniew Dauter, U Derewenda, Christopher A. Walsh, Jacek OtlewskiAbstract:The Doublecortin-like domains (DCX), which typically occur in tandem, are novel microtubule-binding modules. DCX tandems are found in Doublecortin, a 360-residue protein expressed in migrating neurons; the Doublecortin-like kinase (DCLK); the product of the RP1 gene that is responsible for a form of inherited blindness; and several other proteins. Mutations in the gene encoding Doublecortin cause lissencephaly in males and the 'double-cortex syndrome' in females. We here report a solution structure of the N-terminal DCX domain of human Doublecortin and a 1.5 A resolution crystal structure of the equivalent domain from human DCLK. Both show a stable, ubiquitin-like tertiary fold with distinct structural similarities to GTPase-binding domains. We also show that the C-terminal DCX domains of both proteins are only partially folded. In functional assays, the N-terminal DCX domain of Doublecortin binds only to assembled microtubules, whereas the C-terminal domain binds to both microtubules and unpolymerized tubulin.
-
Somatic and germline mosaic mutations in the Doublecortin gene are associated with variable phenotypes.
American Journal of Human Genetics, 2000Co-Authors: Joseph G Gleeson, William B Dobyns, Sharon Minnerath, Ruben Kuzniecky, Ian D. Young, M. Elizabeth Ross, Christopher A. WalshAbstract:Mutations in the X-linked gene Doublecortin lead to “double cortex” syndrome (DC) in females and to X-linked lissencephaly (XLIS) in males. Because most patients with DC and XLIS are sporadic, representing de novo Doublecortin mutations, we considered that some of these patients could be somatic or germline mosaics. Among a population of 20 patients and their families, we found evidence for mosaic Doublecortin mutations in 6 individuals. Germline mosaicism was identified in two unaffected women, each with two affected children. Additionally, one affected male with DC was found to be a somatic mosaic, which presumably spared him from the more severe phenotype of lissencephaly. The high rate of mosaicism indicates that there may be a significant recurrence risk for DC/XLIS in families at risk, even when the mother is unaffected.