1
|
Huang J, Wang C, Ouyang J, Tang H, Zheng S, Xiong Y, Gao Y, Wu Y, Wang L, Yan X, Chen H. Identification of Key Candidate Genes for Beak Length Phenotype by Whole-Genome Resequencing in Geese. Front Vet Sci 2022; 9:847481. [PMID: 35372529 PMCID: PMC8964941 DOI: 10.3389/fvets.2022.847481] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 02/15/2022] [Indexed: 12/14/2022] Open
Abstract
The domestic goose is an important economic animal in agriculture and its beak, a trait with high heritability, plays an important role in promoting food intake and defending against attacks. In this study, we sequenced 772 420-day-old Xingguo gray geese (XGG) using a low-depth (~1 ×) whole-genome resequencing strategy. We detected 12,490,912 single nucleotide polymorphisms (SNPs) using the standard GATK and imputed with STITCH. We then performed a genome-wide association study on the beak length trait in XGG. The results indicated that 57 SNPs reached genome-wide significance levels for the beak length trait and were assigned to seven genes, including TAPT1, DHX15, CCDC149, LGI2, SEPSECS, ANAPC4, and Slc34a2. The different genotypes of the most significant SNP (top SNP), which was located upstream of LGI2 and explained 7.24% of the phenotypic variation in beak length, showed significant differences in beak length. Priority-based significance analysis concluded that CCDC149, LGI2, and SEPSECS genes in the most significant quantitative trait locus interval were the most plausible positional and functional candidate genes for beak length development in the XGG population. These findings not only enhance our understanding of the genetic mechanism of the beak length phenotype in geese, but also lay the foundation for further studies to facilitate the genetic selection of traits in geese.
Collapse
|
2
|
Gawel K, Langlois M, Martins T, van der Ent W, Tiraboschi E, Jacmin M, Crawford AD, Esguerra CV. Seizing the moment: Zebrafish epilepsy models. Neurosci Biobehav Rev 2020; 116:1-20. [PMID: 32544542 DOI: 10.1016/j.neubiorev.2020.06.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/20/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
Zebrafish are now widely accepted as a valuable animal model for a number of different central nervous system (CNS) diseases. They are suitable both for elucidating the origin of these disorders and the sequence of events culminating in their onset, and for use as a high-throughput in vivo drug screening platform. The availability of powerful and effective techniques for genome manipulation allows the rapid modelling of different genetic epilepsies and of conditions with seizures as a core symptom. With this review, we seek to summarize the current knowledge about existing epilepsy/seizures models in zebrafish (both pharmacological and genetic) and compare them with equivalent rodent and human studies. New findings obtained from the zebrafish models are highlighted. We believe that this comprehensive review will highlight the value of zebrafish as a model for investigating different aspects of epilepsy and will help researchers to use these models to their full extent.
Collapse
Affiliation(s)
- Kinga Gawel
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Department of Experimental and Clinical Pharmacology, Medical University of Lublin, Jaczewskiego St. 8b, 20-090, Lublin, Poland
| | | | - Teresa Martins
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Wietske van der Ent
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway
| | - Ettore Tiraboschi
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway; Neurophysics Group, Center for Mind/Brain Sciences, University of Trento, Piazza Manifattura 1, Building 14, 38068, Rovereto, TN, Italy
| | - Maxime Jacmin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg
| | - Alexander D Crawford
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Belval, Luxembourg; Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | - Camila V Esguerra
- Chemical Neuroscience Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo, Gaustadalléen 21, Forskningsparken, 0349, Oslo, Norway.
| |
Collapse
|
3
|
Gerhardt B, Leesman L, Burra K, Snowball J, Rosenzweig R, Guzman N, Ambalavanan M, Sinner D. Notum attenuates Wnt/β-catenin signaling to promote tracheal cartilage patterning. Dev Biol 2018; 436:14-27. [PMID: 29428562 DOI: 10.1016/j.ydbio.2018.02.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 12/20/2022]
Abstract
Tracheobronchomalacia (TBM) is a common congenital disorder in which the cartilaginous rings of the trachea are weakened or missing. Despite the high prevalence and clinical issues associated with TBM, the etiology is largely unknown. Our previous studies demonstrated that Wntless (Wls) and its associated Wnt pathways are critical for patterning of the upper airways. Deletion of Wls in respiratory endoderm caused TBM and ectopic trachealis muscle. To understand mechanisms by which Wls mediates tracheal patterning, we performed RNA sequencing in prechondrogenic tracheal tissue of Wlsf/f;ShhCre/wt embryos. Chondrogenic Bmp4, and Sox9 were decreased, while expression of myogenic genes was increased. We identified Notum, a deacylase that inactivates Wnt ligands, as a target of Wls induced Wnt signaling. Notum's mesenchymal ventral expression in prechondrogenic trachea overlaps with expression of Axin2, a Wnt/β-catenin target and inhibitor. Notum is induced by Wnt/β-catenin in developing trachea. Deletion of Notum activated mesenchymal Wnt/β-catenin and caused tracheal mispatterning of trachealis muscle and cartilage as well as tracheal stenosis. Notum is required for tracheal morphogenesis, influencing mesenchymal condensations critical for patterning of tracheal cartilage and muscle. We propose that Notum influences mesenchymal cell differentiation by generating a barrier for Wnt ligands produced and secreted by airway epithelial cells to attenuate Wnt signaling.
Collapse
Affiliation(s)
- Bradley Gerhardt
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Lauren Leesman
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Kaulini Burra
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - John Snowball
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Rachel Rosenzweig
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Natalie Guzman
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Manoj Ambalavanan
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Debora Sinner
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| |
Collapse
|
4
|
Kegel L, Jaegle M, Driegen S, Aunin E, Leslie K, Fukata Y, Watanabe M, Fukata M, Meijer D. Functional phylogenetic analysis of LGI proteins identifies an interaction motif crucial for myelination. Development 2014; 141:1749-56. [PMID: 24715463 DOI: 10.1242/dev.107995] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The cellular interactions that drive the formation and maintenance of the insulating myelin sheath around axons are only partially understood. Leucine-rich glioma-inactivated (LGI) proteins play important roles in nervous system development and mutations in their genes have been associated with epilepsy and amyelination. Their function involves interactions with ADAM22 and ADAM23 cell surface receptors, possibly in apposing membranes, thus attenuating cellular interactions. LGI4-ADAM22 interactions are required for axonal sorting and myelination in the developing peripheral nervous system (PNS). Functional analysis revealed that, despite their high homology and affinity for ADAM22, LGI proteins are functionally distinct. To dissect the key residues in LGI proteins required for coordinating axonal sorting and myelination in the developing PNS, we adopted a phylogenetic and computational approach and demonstrate that the mechanism of action of LGI4 depends on a cluster of three amino acids on the outer surface of the LGI4 protein, thus providing a structural basis for the mechanistic differences in LGI protein function in nervous system development and evolution.
Collapse
Affiliation(s)
- Linde Kegel
- Erasmus University Medical Center, Biomedical Sciences, Departments of Genetics and Cell Biology, Rotterdam 3015GE, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Abstract
Mutations in the LGI1 gene predispose to autosomal dominant lateral temporal lobe epilepsy, a rare hereditary form with incomplete penetrance and associated with acoustic auras. LGI1 is not a structural component of an ion channel like most epilepsy-related genes, but is a secreted protein. Mutant null mice exhibit early-onset seizures, and electrophysiological analysis shows abnormal synaptic transmission. LGI1 binds to ADAM23 on the presynaptic membrane and ADAM22 on the postsynaptic membrane, further implicating it in regulating the strength of synaptic transmission. Patients with limbic encephalitis show autoantibodies against LGI1 and develop seizures, supporting a role for LGI1 in synapse transmission in the post developmental brain. LGI1, however, also seems to be involved in aspects of neurite development and dendritic pruning, suggesting an additional role in corticogenesis. LGI1 is also involved in cell movement and suppression of dendritic outgrowth in in vitro systems, possibly involving actin cytoskeleton dynamics. Expression patterns in embryonic development correspond to areas of neuronal migration. Loss of LGI1 expression also impacts on myelination of the central and peripheral nervous systems. In zebrafish embryos, knockdown of lgi1a leads to a seizure-like behavior and abnormal brain development, providing a system to study its role in early embryogenesis. Despite being implicated in a role in both synapse transmission and neuronal development, how LGI1 predisposes to epilepsy is still largely unknown. It appears, however, that LGI1 may function differently in a cell context-specific manner, implying a complex involvement in brain development and function that remains to be defined.
Collapse
Affiliation(s)
- John K Cowell
- Georgia Regents University Cancer Center, Augusta, GA, USA.
| |
Collapse
|
6
|
Abstract
The development and function of the vertebrate nervous system depend on specific interactions between different cell types. Two examples of such interactions are synaptic transmission and myelination. LGI1-4 (leucine-rich glioma inactivated proteins) play important roles in these processes. They are secreted proteins consisting of an LRR (leucine-rich repeat) domain and a so-called epilepsy-associated or EPTP (epitempin) domain. Both domains are thought to function in protein–protein interactions. The first LGI gene to be identified, LGI1, was found at a chromosomal translocation breakpoint in a glioma cell line. It was subsequently found mutated in ADLTE (autosomal dominant lateral temporal (lobe) epilepsy) also referred to as ADPEAF (autosomal dominant partial epilepsy with auditory features). LGI1 protein appears to act at synapses and antibodies against LGI1 may cause the autoimmune disorder limbic encephalitis. A similar function in synaptic remodelling has been suggested for LGI2, which is mutated in canine Benign Familial Juvenile Epilepsy. LGI4 is required for proliferation of glia in the peripheral nervous system and binds to a neuronal receptor, ADAM22, to foster ensheathment and myelination of axons by Schwann cells. Thus, LGI proteins play crucial roles in nervous system development and function and their study is highly important, both to understand their biological functions and for their therapeutic potential. Here, we review our current knowledge about this important family of proteins, and the progress made towards understanding their functions.
Collapse
|
7
|
Teng Y, Xie X, Walker S, Saxena M, Kozlowski DJ, Mumm JS, Cowell JK. Loss of zebrafish lgi1b leads to hydrocephalus and sensitization to pentylenetetrazol induced seizure-like behavior. PLoS One 2011; 6:e24596. [PMID: 22053218 PMCID: PMC3203530 DOI: 10.1371/journal.pone.0024596] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 08/15/2011] [Indexed: 11/19/2022] Open
Abstract
Mutations in the LGI1 gene predispose to a hereditary epilepsy syndrome and is the first gene associated with this disease which does not encode an ion channel protein. In zebrafish, there are two paralogs of the LGI1 gene, lgi1a and lgi1b. Knockdown of lgi1a results in a seizure-like hyperactivity phenotype with associated developmental abnormalities characterized by cellular loss in the eyes and brain. We have now generated knockdown morphants for the lgi1b gene which also show developmental abnormalities but do not show a seizure-like behavior. Instead, the most striking phenotype involves significant enlargement of the ventricles (hydrocephalus). As shown for the lgi1a morphants, however, lgi1b morphants are also sensitized to PTZ-induced hyperactivity. The different phenotypes between the two lgi1 morphants support a subfunctionalization model for the two paralogs.
Collapse
Affiliation(s)
- Yong Teng
- GHSU Cancer Center, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Xiayang Xie
- Department of Cellular Biology and Anatomy, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
- Vision Discovery Institute, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Steven Walker
- Department of Cellular Biology and Anatomy, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
- Vision Discovery Institute, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Meera Saxena
- Luminomics Inc, Augusta, Georgia, United States of America
| | - David J. Kozlowski
- Department of Cellular Biology and Anatomy, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
- Program in Developmental Neurobiology, Institute of Molecular Medicine and Genetics, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - Jeff S. Mumm
- Department of Cellular Biology and Anatomy, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
- Vision Discovery Institute, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| | - John K. Cowell
- GHSU Cancer Center, School of Medicine, Georgia Health Sciences University, Augusta, Georgia, United States of America
| |
Collapse
|
8
|
Silva J, Wang G, Cowell JK. The temporal and spatial expression pattern of the LGI1 epilepsy predisposition gene during mouse embryonic cranial development. BMC Neurosci 2011; 12:43. [PMID: 21569517 PMCID: PMC3120723 DOI: 10.1186/1471-2202-12-43] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Accepted: 05/13/2011] [Indexed: 11/20/2022] Open
Abstract
Background Mutations in the LGI1 gene predispose to a rare, hereditary form of temporal epilepsy. Currently, little is known about the temporal and spatial expression pattern of Lgi1 during normal embryogenesis and so to define this more clearly we used a transgenic mouse line that expresses GFP under the control of Lgi1 cis-regulatory elements. Results During embryonic brain growth, high levels of Lgi1 expression were found in the surface ectoderm, the neuroepithelium, mesenchymal connective tissue, hippocampus, and sensory organs, such as eye, tongue, and the olfactory bulb. Lgi1 was also found in the cranial nerve nuclei and ganglia, such as vestibular, trigeminal, and dorsal ganglia. Expression of Lgi1 followed an orchestrated pattern during mouse development becoming more subdued in areas of the neocortex of the mid- and hind-brain in early postnatal animals, although high expression levels were retained in the choroid plexus and hippocampus. In late postnatal stages, Lgi1 expression continued to be detected in many areas in the brain including, hippocampus, paraventricular thalamic nuclei, inferior colliculus, and the cerebral aqueduct. We also showed that Lgi1-expressing cells co-express nestin, DCX, and beta-III tubulin suggesting that Lgi1-expressing cells are migratory neuroblasts. Conclusion These observations imply that Lgi1 may have a role in establishing normal brain architecture and neuronal functions during brain development suggesting that it may be involved in neurogenesis and neuronal plasticity, which become more specifically defined in the adult animal.
Collapse
Affiliation(s)
- Jeane Silva
- GHSU Cancer Center, School of Medicine, Georgia Health Sciences University, Augusta 30912, USA
| | | | | |
Collapse
|
9
|
Leonardi E, Andreazza S, Vanin S, Busolin G, Nobile C, Tosatto SCE. A computational model of the LGI1 protein suggests a common binding site for ADAM proteins. PLoS One 2011; 6:e18142. [PMID: 21479274 PMCID: PMC3066209 DOI: 10.1371/journal.pone.0018142] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 02/23/2011] [Indexed: 01/06/2023] Open
Abstract
Mutations of human leucine-rich glioma inactivated (LGI1) gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE), a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions.A three dimensional in silico model of the two epitempin domains was built to predict the structure-function relationship and propose a functional model integrating previous experimental findings. Conserved and electrostatic charged regions of the model surface suggest a possible arrangement between the two domains and identifies a possible ADAM protein binding site in the β-propeller domain and another protein binding site in the leucine-rich repeat domain. The functional model indicates that epitempin could mediate the interaction between proteins localized to different synaptic sides in a static way, by forming a dimer, or in a dynamic way, by binding proteins at different times.The model was also used to predict effects of known disease-causing missense mutations. Most of the variants are predicted to alter protein folding while several other map to functional surface regions. In agreement with experimental evidence, this suggests that non-secreted LGI1 mutants could be retained within the cell by quality control mechanisms or by altering interactions required for the secretion process.
Collapse
Affiliation(s)
| | | | - Stefano Vanin
- Department of Biology, University of Padova, Padova, Italy
- School of Applied Science, University of Huddersfield, Huddersfield, United Kingdom
| | - Giorgia Busolin
- Institute of Neurosciences, Consiglio Nazionale delle Ricerche (CNR), Padova, Italy
| | - Carlo Nobile
- Institute of Neurosciences, Consiglio Nazionale delle Ricerche (CNR), Padova, Italy
| | | |
Collapse
|
10
|
Silva J, Sharma S, Hughes B, Yu YE, Cowell JK. Homozygous inactivation of the LGI1 gene results in hypomyelination in the peripheral and central nervous systems. J Neurosci Res 2010; 88:3328-36. [PMID: 20857514 PMCID: PMC3885985 DOI: 10.1002/jnr.22496] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mutations in the LGI1 gene in humans predispose to the development of autosomal dominant partial epilepsy with auditory features (ADPEAF). Homozygous inactivation of the Lgi1 gene in mice results in an epilepsy phenotype characterized by clonic seizures within 2-3 weeks after birth. Before onset of seizures, the 2-3-week-old null mutant mice show poor locomotor activity and neuromuscular strength. EM analysis of the sciatic nerve demonstrates impaired myelination of axons in the peripheral nervous system. Although heterozygous mutant mice do not show any locomotor phenotypes, they also demonstrate an intermediate level of hypomyelination compared with the wild-type mice. Hypomyelination was also observed in the central nervous system, which, although relatively mild, was still significantly different from that of the wild-type mice. These data suggest a role for LGI1 in the myelination functions of Schwann cells and oligodendrocytes.
Collapse
Affiliation(s)
- Jeane Silva
- MCG Cancer Center, School of Medicine, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | |
Collapse
|
11
|
Limviphuvadh V, Chua LL, Rahim RAAB, Eisenhaber F, Maurer-Stroh S, Adhikari S. Similarity of molecular phenotype between known epilepsy gene LGI1 and disease candidate gene LGI2. BMC BIOCHEMISTRY 2010; 11:39. [PMID: 20863412 PMCID: PMC2949613 DOI: 10.1186/1471-2091-11-39] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Accepted: 09/24/2010] [Indexed: 11/20/2022]
Abstract
Background The LGI2 (leucine-rich, glioma inactivated 2) gene, a prime candidate for partial epilepsy with pericentral spikes, belongs to a family encoding secreted, beta-propeller domain proteins with EPTP/EAR epilepsy-associated repeats. In another family member, LGI1 (leucine-rich, glioma inactivated 1) mutations are responsible for autosomal dominant lateral temporal epilepsy (ADLTE). Because a few LGI1 disease mutations described in the literature cause secretion failure, we experimentally analyzed the secretion efficiency and subcellular localization of several LGI1 and LGI2 mutant proteins corresponding to observed non-synonymous single nucleotide polymorphisms (nsSNPs) affecting the signal peptide, the leucine-rich repeats and the EAR propeller. Results Mapping of disease-causing mutations in the EAR domain region onto a 3D-structure model shows that many of these mutations co-localize at an evolutionary conserved surface region of the propeller. We find that wild-type LGI2 is secreted to the extracellular medium in glycosylated form similarly to LGI1, whereas several mutant proteins tested in this study are secretion-deficient and accumulate in the endoplasmic reticulum. Interestingly, mutations at structurally homologous positions in the EAR domain have the same effect on secretion in LGI1 and LGI2. Conclusions This similarity of experimental mislocalization phenotypes for mutations at homologous positions of LGI2 and the established epilepsy gene LGI1 suggests that both genes share a potentially common molecular pathogenesis mechanism that might be the reason for genotypically distinct but phenotypically related forms of epilepsy.
Collapse
Affiliation(s)
- Vachiranee Limviphuvadh
- Bioinformatics Institute, Agency for Science, Technology and Research, 30 Biopolis Street, #07-01 Matrix, 138671 Singapore.
| | | | | | | | | | | |
Collapse
|
12
|
Teng Y, Xie X, Walker S, Rempala G, Kozlowski DJ, Mumm JS, Cowell JK. Knockdown of zebrafish Lgi1a results in abnormal development, brain defects and a seizure-like behavioral phenotype. Hum Mol Genet 2010; 19:4409-20. [PMID: 20819949 DOI: 10.1093/hmg/ddq364] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Epilepsy is a common disorder, typified by recurrent seizures with underlying neurological disorders or disease. Approximately one-third of patients are unresponsive to currently available therapies. Thus, a deeper understanding of the genetics and etiology of epilepsy is needed to advance the development of new therapies. Previously, treatment of zebrafish with epilepsy-inducing pharmacological agents was shown to result in a seizure-like phenotype, suggesting that fish provide a tractable model to understand the function of epilepsy-predisposing genes. Here, we report the first model of genetically linked epilepsy in zebrafish and provide an initial characterization of the behavioral and neurological phenotypes associated with morpholino (MO) knockdown of leucine-rich, glioma-inactivated 1a (lgi1a) expression. Mutations in the LGI1 gene in humans have been shown to predispose to a subtype of autosomal dominant epilepsy. Low-dose Lgi1a MO knockdown fish (morphants) appear morphologically normal but are sensitized to epilepsy-inducing drugs. High-dose Lgi1a morphants have morphological defects which persist into adult stages that are typified by smaller brains and eyes and abnormalities in tail shape, and display hyperactive swimming behaviors. Increased apoptosis was observed throughout the central nervous system of high-dose morphant fish, accounting for the size reduction of neural tissues. These observations demonstrate that zebrafish can be exploited to dissect the embryonic function(s) of genes known to predispose to seizure-like behavior in humans, and offer potential insight into the relationship between developmental neurobiological abnormalities and seizure.
Collapse
Affiliation(s)
- Yong Teng
- MCG Cancer Center, Medical College of Georgia, School of Medicine, 1120 15th Street, Augusta, GA 30912, USA
| | | | | | | | | | | | | |
Collapse
|
13
|
Nobile C, Michelucci R, Andreazza S, Pasini E, Tosatto SCE, Striano P. LGI1 mutations in autosomal dominant and sporadic lateral temporal epilepsy. Hum Mutat 2009; 30:530-6. [PMID: 19191227 DOI: 10.1002/humu.20925] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Autosomal dominant lateral temporal epilepsy (ADLTE) or autosomal dominant partial epilepsy with auditory features (ADPEAF) is an inherited epileptic syndrome with onset in childhood/adolescence and benign evolution. The hallmark of the syndrome consists of typical auditory auras or ictal aphasia in most affected family members. ADTLE/ADPEAF is associated in about half of the families with mutations of the leucine-rich, glioma-inactivated 1 (LGI1) gene. In addition, de novo LGI1 mutations are found in about 2% of sporadic cases with idiopathic partial epilepsy with auditory features, who are clinically similar to the majority of patients with ADLTE/ADPEAF but have no family history. Twenty-five LGI1 mutations have been described in familial and sporadic lateral temporal epilepsy patients. The mutations are distributed throughout the gene and are mostly missense mutations occurring in both the N-terminal leucine rich repeat (LRR) and C-terminal EPTP (beta propeller) protein domains. We show a tridimensional model of the LRR protein region that allows missense mutations of this region to be divided into two distinct groups: structural and functional mutations. Frameshift, nonsense and splice site point mutations have also been reported that result in protein truncation or internal deletion. The various types of mutations are associated with a rather homogeneous phenotype, and no obvious genotype-phenotype correlation can be identified. Both truncating and missense mutations appear to prevent secretion of mutant proteins, suggesting a loss of function effect of mutations. The function of LGI1 is unclear. Several molecular mechanisms possibly leading to lateral temporal epilepsy are illustrated and briefly discussed.
Collapse
Affiliation(s)
- Carlo Nobile
- Istituto di Neuroscienze del CNR, Sezione di Padova, Dipartimento di Scienze Biomediche Sperimentali, Università di Padova, Padova, Italy.
| | | | | | | | | | | |
Collapse
|
14
|
Møller RS, Hansen CP, Jackson GD, Ullmann R, Ropers HH, Tommerup N, Tümer Z. Interstitial deletion of chromosome 4p associated with mild mental retardation, epilepsy and polymicrogyria of the left temporal lobe. Clin Genet 2007; 72:593-8. [DOI: 10.1111/j.1399-0004.2007.00901.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
15
|
Luo J, Lang M, Salzburger W, Siegel N, Stölting KN, Meyer A. A BAC library for the goldfish Carassius auratus auratus (Cyprinidae, Cypriniformes). JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2007; 306:567-74. [PMID: 16708366 DOI: 10.1002/jez.b.21112] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A goldfish (Carassius auratus auratus) bacterial artificial chromosome genomic library (BAC library) was constructed from one aquarium-bred male specimen (tetraploid, 4n=100, genome size=3.52 pg/cell). The library consists of 128,352 positive clones with an average insert size of 150.4 kb, covering the genome 11-fold. All clones were spotted onto nylon filters and thus are available for screening of genomic regions of interest, such as candidate genes, gene families, or large-sized syntenic DNA regions of cyprinid species. Preliminary screens with two genes were conducted with hybridizing probes to the genes RAG1 and lgi1. RAG1 is a single-copy gene in zebrafish and is duplicated in C. a. auratus. We found a very close correlation between the number of positive BAC clones and the expected library coverage. Two copies of lgi1 were found in zebrafish. We have detected four different copies in C. a. auratus, not in the expected abundance, which indicates some variation in the coverage of the BAC library. The preliminary screens indicate that many duplicated genes that resulted from the ancient fish-specific genome duplication persist in the tetraploid goldfish genome. Hence, the BAC library will provide a useful resource for the future work on comparative genomics, polyploidy, diploidization, and evolutionary genomics in fishes.
Collapse
Affiliation(s)
- Jing Luo
- Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Konstanz, Germany.
| | | | | | | | | | | |
Collapse
|
16
|
Ayerdi-Izquierdo A, Stavrides G, Sellés-Martínez JJ, Larrea L, Bovo G, López de Munain A, Bisulli F, Martí-Massó JF, Michelucci R, Poza JJ, Tinuper P, Stephani U, Striano P, Striano S, Staub E, Sarafidou T, Hinzmann B, Moschonas N, Siebert R, Deloukas P, Nobile C, Pérez-Tur J. Genetic analysis of the LGI/Epitempin gene family in sporadic and familial lateral temporal lobe epilepsy. Epilepsy Res 2006; 70:118-26. [PMID: 16707245 DOI: 10.1016/j.eplepsyres.2006.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 01/30/2006] [Accepted: 03/19/2006] [Indexed: 11/26/2022]
Abstract
Mutations in the LGI1/Epitempin gene cause autosomal dominant lateral temporal lobe epilepsy (ADLTE), a partial epilepsy characterized by the presence of auditory seizures. However, not all the pedigrees with a phenotype consistent with ADLTE show mutations in LGI1/Epitempin, or evidence for linkage to the 10q24 locus. Other authors as well as ourselves have found an internal repeat (EPTP, pfam# PF03736) that allowed the identification of three other genes sharing a sequence and structural similarity with LGI1/Epitempin. In this work, we present the sequencing of these genes in a set of ADLTE families without mutations in both LGI1/Epitempin and sporadic cases. No analyzed polymorphisms modified susceptibility in either the familial or sporadic forms of this partial epilepsy.
Collapse
Affiliation(s)
- A Ayerdi-Izquierdo
- Unitat de Genètica Molecular, Dept. de Genòmica i Proteòmica, Institut de Biomedicina de València - CSIC, Jaume Roig, 11. E46010 València, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|