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Sieghart W, Savić MM. International Union of Basic and Clinical Pharmacology. CVI: GABAA Receptor Subtype- and Function-selective Ligands: Key Issues in Translation to Humans. Pharmacol Rev 2018; 70:836-878. [DOI: 10.1124/pr.117.014449] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Saari TI, Uusi-Oukari M, Ahonen J, Olkkola KT. Enhancement of GABAergic activity: neuropharmacological effects of benzodiazepines and therapeutic use in anesthesiology. Pharmacol Rev 2011; 63:243-67. [PMID: 21245208 DOI: 10.1124/pr.110.002717] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
GABA is the major inhibitory neurotransmitter in the central nervous system (CNS). The type A GABA receptor (GABA(A)R) system is the primary pharmacological target for many drugs used in clinical anesthesia. The α1, β2, and γ2 subunit-containing GABA(A)Rs located in the various parts of CNS are thought to be involved in versatile effects caused by inhaled anesthetics and classic benzodiazepines (BZD), both of which are widely used in clinical anesthesiology. During the past decade, the emergence of tonic inhibitory conductance in extrasynaptic GABA(A)Rs has coincided with evidence showing that these receptors are highly sensitive to the sedatives and hypnotics used in anesthesia. Anesthetic enhancement of tonic GABAergic inhibition seems to be preferentially increased in regions shown to be important in controlling memory, awareness, and sleep. This review focuses on the physiology of the GABA(A)Rs and the pharmacological properties of clinically used BZDs. Although classic BZDs are widely used in anesthesiological practice, there is a constant need for new drugs with more favorable pharmacokinetic and pharmacodynamic effects and fewer side effects. New hypnotics are currently developed, and promising results for one of these, the GABA(A)R agonist remimazolam, have recently been published.
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Affiliation(s)
- Teijo I Saari
- Department of Anesthesiology, Intensive Care, Emergency Care and Pain Medicine, Turku University Hospital, P.O. Box 52 (Kiinamyllynkatu 4-8), FI-20520 Turku, Finland.
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Cunningham D, Talabere T, Bir N, Kennedy M, McBride KL, Herman GE. Significant contributions of the extraembryonic membranes and maternal genotype to the placental pathology in heterozygous Nsdhl deficient female embryos. Hum Mol Genet 2009; 19:364-73. [PMID: 19880419 DOI: 10.1093/hmg/ddp502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Mutations in the gene encoding the cholesterol biosynthetic enzyme NSDHL are associated with the X-linked male-lethal bare patches (Bpa) mouse. Mutant male embryos for several Nsdhl alleles die in midgestation with placental insufficiency. We examined here a possible role of the maternal genotype in such placental pathology. Pre-pregnancy plasma cholesterol levels were similar between wild-type (WT) and Bpa(1H)/+ dams fed a standard, cholesterol-free diet. However, there was a marked decrease in cholesterol levels between embryonic day (E)8.5 and E10.5 for both genotypes. Further, there was a significant lag between E11.5 and E13.5 (P = 0.0011) in the recovery of levels in Bpa(1H)/+ dams to their pre-pregnancy values. To investigate possible effects of the maternal genotype on fetal placentation, we generated transgenic mice that expressed human NSDHL and rescued the male lethality of the Bpa(1H) null allele. We then compared placenta area at E10.5 in WT and Bpa(1H)/+ female embryos where the mutant X chromosome was transmitted from a heterozygous mother or a rescued mutant father. In mutant conceptuses, placental areas were approximately 50% less than WT. Surprisingly, expression of Nsdhl in trophoblast lineages of the placenta and yolk sac endoderm, which occurs only from the maternally inherited allele in a female embryo, had the largest effect on placental area (-0.681 mm(2); P < 0.0001). The maternal genotype had a smaller effect, independent of the fetal genotype (-0.283 mm(2); P = 0.024). These data demonstrate significant effects of the mother and fetal membranes on pregnancy outcome, with possible implications for cholesterol homeostasis during human pregnancy.
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Affiliation(s)
- David Cunningham
- Department of Pediatrics, The Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH 43205, USA
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Menezes AH, Vogel TW. Specific entities affecting the craniocervical region: syndromes affecting the craniocervical junction. Childs Nerv Syst 2008; 24:1155-63. [PMID: 18369644 DOI: 10.1007/s00381-008-0608-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Indexed: 12/28/2022]
Abstract
INTRODUCTION The craniocervical junction is a vital component in understanding the function of the human central nervous system. It is the threshold for major pathways affecting both brain and spinal cord function, and these structures are intricately housed in a network of bone, ligaments, and soft tissues. Abnormal development of any of these components may lead to altered structure, and therefore, altered function in the central nervous system. MATERIALS AND METHODS We herein describe a set of genetic syndromes that commonly affect the craniovertebral junction and offer clinical examples from more than 6,000 patients who have been treated for these disorders. DISCUSSION The syndromes described include Chiari type I malformation, Conradi syndrome, Goldenhar syndrome, Klippel-Feil syndrome, Larsen syndrome, Morquio syndrome, Pierre-Robin syndrome, spondyloepiphyseal dysplasia congenital and Weaver syndrome. The genetic mechanisms responsible for these disorders may offer unique insight into the developmental pathways and patterning in the musculoskeletal and cranial systems and may, ultimately, guide future diagnosis and treatment.
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Affiliation(s)
- Arnold H Menezes
- Department of Neurosurgery, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, 1824 JPP, Iowa, IA 52242, USA.
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Molecular cloning and characterization of a novel mouse actin-binding protein Zfp185. J Mol Histol 2008; 39:295-302. [PMID: 18239999 DOI: 10.1007/s10735-008-9165-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Accepted: 01/22/2008] [Indexed: 12/11/2022]
Abstract
Zinc finger protein (Zfp) 185 is a mouse protein containing a Lin-l1, Isl-1 and Mec-3 (LIM) domains at its C-terminus. It was recognized by comparing the genome sequence between humans and mice in 1997. In this study, we cloned the full-length Zfp185 by means of RACE and RT-PCR. Zfp185 may be closely associated with F-actin in cells as determined by a confocal microscopy. With a series of deletants of Zfp185 and GST-pull-down assay, we determined that N-terminus region (1-144) but not the LIM domain at C-terminus of Zfp185 protein was essential and sufficient to bind to F-actin cytoskeleton. Thus, our data offered evidence for the association of mouse Zfp185 with F-actin, which supports the potential role of Zfp185 in cell fundamental activity.
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Davies W, Isles A, Smith R, Karunadasa D, Burrmann D, Humby T, Ojarikre O, Biggin C, Skuse D, Burgoyne P, Wilkinson L. Xlr3b is a new imprinted candidate for X-linked parent-of-origin effects on cognitive function in mice. Nat Genet 2005; 37:625-9. [PMID: 15908950 DOI: 10.1038/ng1577] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Accepted: 04/27/2005] [Indexed: 12/23/2022]
Abstract
Imprinted genes show differential expression between maternal and paternal alleles as a consequence of epigenetic modification that can result in 'parent-of-origin' effects on phenotypic traits. There is increasing evidence from mouse and human studies that imprinted genes may influence behavior and cognitive functioning. Previous work in girls with Turner syndrome (45,XO) has suggested that there are X-linked parent-of-origin effects on brain development and cognitive functioning, although the interpretation of these data in terms of imprinted gene effects has been questioned. We used a 39,XO mouse model to examine the influence of the parental origin of the X chromosome on cognitive behaviors and expression of X-linked genes in brain. Our findings confirm the existence of X-linked imprinted effects on cognitive processes and identify a new maternally expressed imprinted gene candidate on the X chromosome, Xlr3b, which may be of importance in mediating the behavioral effects.
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Affiliation(s)
- William Davies
- Laboratories of Cognitive and Behavioral Neuroscience and Developmental Genetics and Imprinting, The Babraham Institute, The Babraham Research Campus, Cambridge, CB2 4AT, UK
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Cunningham D, Swartzlander D, Liyanarachchi S, Davuluri RV, Herman GE. Changes in gene expression associated with loss of function of the NSDHL sterol dehydrogenase in mouse embryonic fibroblasts. J Lipid Res 2005; 46:1150-62. [PMID: 15805545 DOI: 10.1194/jlr.m400462-jlr200] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Seven human disorders of postsqualene cholesterol biosynthesis have been described. One of these, congenital hemidysplasia with ichthyosiform nevus and limb defects (CHILD) syndrome, results from mutations in the X-linked gene NADH sterol dehydrogenase-like (NSDHL) encoding a sterol dehydrogenase. A series of mutant alleles of the murine Nsdhl gene are carried by bare patches (Bpa) mice, with Bpa(1H) representing a null allele. Heterozygous Bpa(1H) females display skin and skeletal abnormalities in a distribution reflecting random X inactivation, whereas hemizygous male embryos die before embryonic day 10.5. To investigate the molecular basis of defects associated with perturbations in cholesterol biosynthesis, microarray analysis was performed comparing gene expression in embryonic fibroblasts expressing the Bpa(1H) allele versus wild-type (wt) cells. Labeled cDNAs from cells grown in normal serum or lipid-depleted serum (LDS) were hybridized to microarrays containing 22,000 mouse genes. Among 44 genes that showed higher expression in the Bpa(1H) versus wt cells grown in LDS, 11 function in cholesterol biosynthesis, 7 are involved in fatty acid synthesis, 3 (Srebp2, Insig1, and Orf11) encode sterol-regulatory proteins, and 2 (Ldlr and StarD4) are lipid transporters. Of the 21 remaining genes, 16 are known genes, some of which have been implicated previously in cholesterol homeostasis or lipid-mediated signaling, and 5 are uncharacterized cDNA clones.
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Affiliation(s)
- David Cunningham
- Center for Molecular and Human Genetics, Columbus Children's Research Institute, Ohio State University, Columbus, OH, USA
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Simon J, Wakimoto H, Fujita N, Lalande M, Barnard EA. Analysis of the Set of GABAA Receptor Genes in the Human Genome. J Biol Chem 2004; 279:41422-35. [PMID: 15258161 DOI: 10.1074/jbc.m401354200] [Citation(s) in RCA: 192] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The genes of the ionotropic gamma-aminobutyric acid receptor (GABR) subunits have shown an unusual chromosomal clustering, but only now can this be fully specified by analyses of the human genome. We have characterized the genes encoding the 18 known human GABR subunits, plus one now located here, for their precise locations, sizes, and exon/intron structures. Clusters of 17 of the 19, distributed between five chromosomes, are specified in detail, and their possible significance is considered. By applying search algorithms designed to recognize sequences of all known GABR-type subunits in species from man down to nematodes, we found no new GABR subunit is detectable in the human genome. However, the sequence of the human orthologue of the rat GABR rho3 receptor subunit was uncovered by these algorithms, and its gene could be analyzed. Consistent with those search results, orthologues of the beta4 and gamma4 subunits from the chicken, not cloned from mammals, were not detectable in the human genome by specific searches for them. The relationships are consistent with the mammalian subunit being derived from the beta line and epsilon from the gamma line, with mammalian loss of beta4 and gamma4. In their structures the human GABR genes show a basic pattern of nine coding exons, with six different genomic mechanisms for the alternative splicing found in various subunits. Additional noncoding exons occur for certain subunits, which can be regulatory. A dicysteine loop and its exon show remarkable constancy between all GABR subunits and species, of deduced functional significance.
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Affiliation(s)
- Joseph Simon
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, United Kingdom
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Steiger JL, Russek SJ. GABAA receptors: building the bridge between subunit mRNAs, their promoters, and cognate transcription factors. Pharmacol Ther 2004; 101:259-81. [PMID: 15031002 DOI: 10.1016/j.pharmthera.2003.12.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The type A gamma-aminobutyric acid (GABA(A)) receptors mediate the majority of fast inhibitory neurotransmission in the CNS, and alterations in GABA(A) receptor function is believed to be involved in the pathology of several neurological and psychiatric illnesses, such as epilepsy, anxiety, Alzheimer's disease, and schizophrenia. GABA(A) receptors can be assembled from eight distinct subunit families defined by sequence similarity: alpha(1-6), beta(1-3), gamma(1-3), delta, pi, theta, and rho(1-3). The regulation of GABA(A) receptor function in the brain is a highly compensating system, influencing both the number and the composition of receptors at the cell surface. While transcriptional and translational points of control operate in parallel, it is becoming increasingly evident that many functional changes in GABA(A) receptors reflect the differential gene regulation of its subunits. The fact that certain GABA(A) receptor subunit genes are transcribed in distinct cell types during specific periods of development strongly suggests that genetic control plays a major role in the choice of subunit variants available for receptor assembly. This review focuses on the physiological conditions that alter subunit mRNA levels, the promoters that may control such levels, and the use of a conceptual framework created by bioinformatics to study coordinate and independent GABA(A) receptor subunit gene regulation. As this exciting field moves closer to identifying the language hidden inside the chromatin of GABA(A) receptor subunit gene clusters, future experiments will be aimed at testing models generated by computational analysis with biologically relevant in vivo and in vitro assays. It is hoped that through this functional genomic approach there will be the identification of new targets for therapeutic intervention.
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Affiliation(s)
- Janine L Steiger
- Laboratory of Molecular Neurobiology, Department of Pharmacology, Boston University School of Medicine, Boston, MA 02118, USA
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Watanabe M, Maemura K, Kanbara K, Tamayama T, Hayasaki H. GABA and GABA receptors in the central nervous system and other organs. INTERNATIONAL REVIEW OF CYTOLOGY 2002; 213:1-47. [PMID: 11837891 DOI: 10.1016/s0074-7696(02)13011-7] [Citation(s) in RCA: 356] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gamma-aminobutyrate (GABA) is a major inhibitory neurotransmitter in the adult mammalian brain. GABA is also considered to be a multifunctional molecule that has different situational functions in the central nervous system, the peripheral nervous system, and in some nonneuronal tissues. GABA is synthesized primarily from glutamate by glutamate decarboxylase (GAD), but alternative pathways may be important under certain situations. Two types of GAD appear to have significant physiological roles. GABA functions appear to be triggered by binding of GABA to its ionotropic receptors, GABA(A) and GABA(C), which are ligand-gated chloride channels, and its metabotropic receptor, GABA(B). The physiological, pharmacological, and molecular characteristics of GABA(A) receptors are well documented, and diversity in the pharmacologic properties of the receptor subtypes is important clinically. In addition to its role in neural development, GABA appears to be involved in a wide variety of physiological functions in tissues and organs outside the brain.
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Aradhya S, Woffendin H, Bonnen P, Heiss NS, Yamagata T, Esposito T, Bardaro T, Poustka A, D'Urso M, Kenwrick S, Nelson DL. Physical and genetic characterization reveals a pseudogene, an evolutionary junction, and unstable loci in distal Xq28. Genomics 2002; 79:31-40. [PMID: 11827455 DOI: 10.1006/geno.2001.6680] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A large portion of human Xq28 has been completely characterized but the interval between G6PD and Xqter has remained poorly understood. Because of a lack of stable, high-density clone coverage in this region, we constructed a 1.6-Mb bacterial and P1 artificial chromosome (BAC and PAC, respectively) contig to expedite mapping, structural and evolutionary analysis, and sequencing. The contig helped to reposition previously mismapped genes and to characterize the XAP135 pseudogene near the int22h-2 repeat. BAC clones containing the distal int22h repeats also demonstrated spontaneous rearrangements and sparse coverage, which suggested that they were unstable. Because the int22h repeats are involved in genetic diseases, we examined them in great apes to see if they have always been unstable. Differences in copy number among the apes, due to duplications and deletions, indicated that they have been unstable throughout their evolution. Taking another approach toward understanding the genomic nature of distal Xq28, we examined the homologous mouse region and found an evolutionary junction near the distal int22h loci that separated the human distal Xq28 region into two segments on the mouse X chromosome. Finally, haplotype analysis showed that a segment within Xq28 has resisted excessive interchromosomal exchange through great ape evolution, potentially accounting for the linkage disequilibrium recently reported in this region. Collectively, these data highlight some interesting features of the genomic sequence in Xq28 and will be useful for positional cloning efforts, mouse mutagenesis studies, and further evolutionary analyses.
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Affiliation(s)
- Swaroop Aradhya
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza 902E, Houston, TX 77030, USA
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Rue SW, Kim BW, Jun DY, Kim YH. Nucleotide sequence and cell cycle-associated differential expression of ZF5128, a novel Kruppel type zinc finger protein gene. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1522:230-7. [PMID: 11779640 DOI: 10.1016/s0167-4781(01)00337-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The nucleotide sequence of the ZF5128 gene, encoding a novel Kruppel type zinc finger protein, has been determined. The ZF5128 gene has a predicted 553-amino acid open reading frame, encoding a putative 61 kDa zinc finger protein. The N-terminus of the ZF5128 coding region has a well-conserved Kruppel-associated box (KRAB) domain that consists of KRAB box A and B, whereas the C-terminus contains a Kruppel type C2H2 zinc finger domain possessing nine C2H2 zinc finger motifs in tandem arrays with the highly conserved space region of the H/C-link. Each C2H2 zinc finger motif has a typical consensus sequence of CX2CX3FX5LX2HX3H. A 3.2 kb transcript specific for ZF5128 was expressed at high levels in the spleen, thymus, and peripheral blood leukocyte, and weakly expressed in the prostate, ovary, small intestine, colon (mucosal lining), placenta, lung, and pancreas. Although there was no detectable ZF5128 mRNA in unstimulated human peripheral T cells, it was first detectable 1.5 h after activation by anti-CD3 plus anti-CD28, and reached a maximum in 25-30 h. During the cell cycle progression of Jurkat T cells, the expression of ZF5128 mRNA appeared to be induced in G1 and reached a maximum in the S phase, but declined as the cells entered the G2/M phase. The 12-O-tetradecanoylphorbol 13-acetate-induced monocytic differentiation of U937, which also resulted in growth arrest, down-regulated the expression of ZF5128 mRNA. Taken together, these results indicate that ZF5128 is a novel gene encoding a Kruppel type C2H2 zinc finger protein and is regulated at the transcriptional level depending on tissue type and the cell cycle status to support cell proliferation.
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Affiliation(s)
- S W Rue
- Department of Microbiology, College of Natural Sciences, Kyungpook National University, 702-701, Taegu, South Korea
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Abstract
Over the past few years, the number of identified inborn errors of cholesterol biosynthesis has increased significantly. The first inborn error of cholesterol biosynthesis to be characterized, in the mid 1980s, was mevalonic aciduria. In 1993, Irons et al. ( 1 ) (M. Irons, E. R. Elias, G. Salen, G. S. Tint, and A. K. Batta, Lancet 341:1414, 1993) reported that Smith-Lemli-Opitz syndrome, a classic autosomal recessive malformation syndrome, was due to an inborn error of cholesterol biosynthesis. This was the first inborn error of postsqualene cholesterol biosynthesis to be identified, and subsequently additional inborn errors of postsqualene cholesterol biosynthesis have been characterized to various extent. To date, eight inborn errors of cholesterol metabolism have been described in human patients or in mutant mice. The enzymatic steps impaired in these inborn errors of metabolism include mevolonate kinase (mevalonic aciduria as well as hyperimmunoglobulinemia D and periodic fever syndrome), squalene synthase (Ss-/- mouse), 3beta-hydroxysteroid Delta14-reductase (hydrops-ectopic calcification-moth-eaten skeletal dysplasia), 3beta-hydroxysteroid dehydrogenase (CHILD syndrome, bare patches mouse, and striated mouse), 3beta-hydroxysteroid Delta8,Delta7-isomerase (X-linked dominant chondrodysplasia punctata type 2, CHILD syndrome, and tattered mouse), 3beta-hydroxysteroid Delta24-reductase (desmosterolosis) and 3beta-hydroxysteroid Delta7-reductase (RSH/Smith-Lemli-Opitz syndrome and Dhcr7-/- mouse). Identification of the genetic and biochemical defects which give rise to these syndromes has provided the first step in understanding the pathophysiological processes which underlie these malformation syndromes.
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Affiliation(s)
- N A Nwokoro
- Heritable Disorders Branch, National Institutes of Health, Bethesda, Maryland 20892, USA
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Miwako I, Yamamoto A, Kitamura T, Nagayama K, Ohashi M. Cholesterol requirement for cation-independent mannose 6-phosphate receptor exit from multivesicular late endosomes to the Golgi. J Cell Sci 2001; 114:1765-76. [PMID: 11309206 DOI: 10.1242/jcs.114.9.1765] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The regulation of endocytic traffic of receptors has central importance in the fine tuning of cell activities. Here, we provide evidence that cholesterol is required for the exit of cation-independent mannose 6-phosphate receptor (CI-MPR) from the endosomal carrier vesicle/multivesicular bodies (ECV/MVBs) to the Golgi. A previously established Chinese hamster ovary cell mutant, LEX2, exhibits arrested ECV/MVBs in which CI-MPR and lysosomal glycoprotein-B (lgp-B) are accumulated. The abnormal accumulation of CI-MPR within the ECV/MVBs in LEX2 cells was corrected in a post-translational manner by the supplementation of medium with cholesterol. Furthermore, it was shown that, by expression cloning using LEX2 mutant, the introduction of the NAD(P)H steroid dehydrogenase-like protein, an enzyme involved in the later stage of cholesterol biosynthesis, allows the exit of CI-MPR from the MVBs to the Golgi and reduces the number of arrested ECV/MVBs in LEX2 cells. The recovery of the exit transport of CI-MPR from the ECV/MVBs was associated with the restoration of the normal cellular free cholesterol level and segregation between CI-MPR and lgp-B, both of which had been localized at the internal small vesicles of the arrested ECV/MVBs. By contrast, the restoration of cholesterol failed to correct the defective processing of endocytosed LDL to a degradative compartment in LEX2 cells. These results suggest that cholesterol is required for ECV/MVB reorganization that drives the sorting/transport of materials destined for the Golgi out of the pathways towards lysosomes.
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Affiliation(s)
- I Miwako
- Dept of Molecular Physiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
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Jiang Z, Gibson JP, Archibald AL, Haley CS. The porcine gonadotropin-releasing hormone receptor gene (GNRHR): Genomic organization, polymorphisms, and association with the number of corpora lutea. Genome 2001. [DOI: 10.1139/g00-083] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The interaction of gonadotropin-releasing hormone (GNRH) and its receptor (GNRHR) is critical in the endocrine regulation of reproduction. The gene (GNRHR) encoding the receptor has been mapped to porcine chromosome 8. There is evidence for three quantitative trait loci (QTL) influencing ovulation rate on this chromosome. We obtained an almost complete sequence (3993 bp, excluding intron 1) of the porcine GNRHR gene using PCR-based comparative genomic walking and inverse genomic walking approaches. Twelve polymorphisms were detected by sequencing of pooled DNA of Chinese Taihu and European Large White pigs, including 7 base substitutions and 5 insertions-deletions (indels). A F2 population of Meishan × European Large White pigs was genotyped for a TG indel in the promoter region, and a C/G substitution in the 3' UTR (untranslated region). A significant association of the C/G substitution with number of corpora lutea at first parity was observed.Key words: porcine GNRHR, genomic organization, polymorphisms, association, corpora lutea.
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Mallon AM, Platzer M, Bate R, Gloeckner G, Botcherby MR, Nordsiek G, Strivens MA, Kioschis P, Dangel A, Cunningham D, Straw RN, Weston P, Gilbert M, Fernando S, Goodall K, Hunter G, Greystrong JS, Clarke D, Kimberley C, Goerdes M, Blechschmidt K, Rump A, Hinzmann B, Mundy CR, Miller W, Poustka A, Herman GE, Rhodes M, Denny P, Rosenthal A, Brown SD. Comparative genome sequence analysis of the Bpa/Str region in mouse and Man. Genome Res 2000; 10:758-75. [PMID: 10854409 PMCID: PMC310879 DOI: 10.1101/gr.10.6.758] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The progress of human and mouse genome sequencing programs presages the possibility of systematic cross-species comparison of the two genomes as a powerful tool for gene and regulatory element identification. As the opportunities to perform comparative sequence analysis emerge, it is important to develop parameters for such analyses and to examine the outcomes of cross-species comparison. Our analysis used gene prediction and a database search of 430 kb of genomic sequence covering the Bpa/Str region of the mouse X chromosome, and 745 kb of genomic sequence from the homologous human X chromosome region. We identified 11 genes in mouse and 13 genes and two pseudogenes in human. In addition, we compared the mouse and human sequences using pairwise alignment and searches for evolutionary conserved regions (ECRs) exceeding a defined threshold of sequence identity. This approach aided the identification of at least four further putative conserved genes in the region. Comparative sequencing revealed that this region is a mosaic in evolutionary terms, with considerably more rearrangement between the two species than realized previously from comparative mapping studies. Surprisingly, this region showed an extremely high LINE and low SINE content, low G+C content, and yet a relatively high gene density, in contrast to the low gene density usually associated with such regions.
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Affiliation(s)
- A M Mallon
- MRC UK Mouse Genome Centre and Mammalian Genetics Unit, Harwell, Oxon, UK
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GABA(A) receptor epsilon and theta subunits display unusual structural variation between species and are enriched in the rat locus ceruleus. J Neurosci 2000. [PMID: 10804200 DOI: 10.1523/jneurosci.20-10-03588.2000] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Previously, GABA(A) receptor epsilon and theta subunits have been identified only in human. Here, we describe properties of the epsilon and theta subunit genes from mouse and rat that reveal an unusually high level of divergence from their human homologs. In addition to a low level of amino acid sequence conservation ( approximately 70%), the rodent epsilon subunit cDNAs encode a unique Pro/Glx motif of approximately 400 residues within the N-terminal extracellular domain of the subunits. Transcripts of the rat epsilon subunit were detected in brain and heart, whereas the mouse theta subunit mRNA was detectable in brain, lung, and spleen by Northern blot analysis. In situ hybridization revealed a particularly strong signal for both subunit mRNAs in rat locus ceruleus in which expression was detectable from the first postnatal day. Lower levels of coexpression were also detected in other brainstem nuclei and in the hypothalamus. However, the expression pattern of theta subunit mRNA was more widespread than that of epsilon subunit, being found also in the cerebral cortex of rat pups. In contrast to primate brain, neither subunit was expressed in the hippocampus or substantia nigra. The results indicate that GABA(A) receptor epsilon and theta subunits are evolving at a much faster rate than other known GABA(A) receptor subunits and that their expression patterns and functional properties may differ significantly between species.
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Aradhya S, Nelson DL, Heiss NS, Poustka A, Woffendin H, Kenwrick S, Esposito T, Ciccodicola A, Bardaro T, D'Urso M, Smahi A, Munnich A, Herman GE, Lewis RA. Human homologue of the murine bare patches/striated gene is not mutated in incontinentia pigmenti type 2. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 91:241-4. [PMID: 10756353 DOI: 10.1002/(sici)1096-8628(20000320)91:3<241::aid-ajmg19>3.0.co;2-j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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K�nig A, Happle R, Bornholdt D, Engel H, Grzeschik KH. Mutations in the NSDHL gene, encoding a 3?-hydroxysteroid dehydrogenase, cause CHILD syndrome. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/(sici)1096-8628(20000214)90:4<339::aid-ajmg15>3.0.co;2-5] [Citation(s) in RCA: 216] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Human neuronal gamma-aminobutyric acid(A) receptors: coordinated subunit mRNA expression and functional correlates in individual dentate granule cells. J Neurosci 1999. [PMID: 10493732 DOI: 10.1523/jneurosci.19-19-08312.1999] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
gamma-Aminobutyric acid(A) receptors (GABARs) are heteromeric proteins composed of multiple subunits. Numerous subunit subtypes are expressed in individual neurons, which assemble in specific preferred GABAR configurations. Little is known, however, about the coordination of subunit expression within individual neurons or the impact this may have on GABAR function. To investigate this, it is necessary to profile quantitatively the expression of multiple subunit mRNAs within individual cells. In this study, single-cell antisense RNA amplification was used to examine the expression of 14 different GABAR subunit mRNAs simultaneously in individual human dentate granule cells (DGCs) harvested during hippocampectomy for intractable epilepsy. alpha4, beta2, and delta-mRNA levels were tightly correlated within individual DGCs, indicating that these subunits are expressed coordinately. Levels of alpha3- and beta2-mRNAs, as well as epsilon- and beta1-mRNAs, also were strongly correlated. No other subunit correlations were identified. Coordinated expression could not be explained by the chromosomal clustering of GABAR genes and was observed in control and epileptic rats as well as in humans, suggesting that it was not species-specific or secondary to epileptogenesis. Benzodiazepine augmentation of GABA-evoked currents also was examined to determine whether levels of subunit mRNA expression correlated with receptor pharmacology. This analysis delineated two distinct cell populations that differed in clonazepam modulation and patterns of alpha-subunit expression. Clonazepam augmentation correlated positively with the relative expression of alpha1- and gamma2-mRNAs and negatively with alpha4- and delta-mRNAs. These data demonstrate that specific GABAR subunit mRNAs exhibit coordinated control of expression in individual DGCs, which has significant impact on inhibitory function.
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21
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Bonnert TP, McKernan RM, Farrar S, le Bourdellès B, Heavens RP, Smith DW, Hewson L, Rigby MR, Sirinathsinghji DJ, Brown N, Wafford KA, Whiting PJ. theta, a novel gamma-aminobutyric acid type A receptor subunit. Proc Natl Acad Sci U S A 1999; 96:9891-6. [PMID: 10449790 PMCID: PMC22306 DOI: 10.1073/pnas.96.17.9891] [Citation(s) in RCA: 257] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
gamma-Aminobutyric acid type A (GABA-A) receptors are a major mediator of inhibitory neurotransmission in the mammalian central nervous system, and the site of action of a number of clinically important drugs. These receptors exist as a family of subtypes with distinct temporal and spatial patterns of expression and distinct properties that presumably underlie a precise role for each subtype. The newest member of this gene family is the theta subunit. The deduced polypeptide sequence is 627 amino acids long and has highest sequence identity (50.5%) with the beta1 subunit. Within the rat striatum, this subunit coassembles with alpha2, beta1, and gamma1, suggesting that gamma-aminobutyric acid type A receptors consisting of arrangements other than alpha beta + gamma, delta, or epsilon do exist. Expression of alpha2beta1gamma1theta in transfected mammalian cells leads to the formation of receptors with a 4-fold decrease in the affinity for gamma-aminobutyric acid compared with alpha2beta1gamma1. This subunit has a unique distribution, with studies so far suggesting significant expression within monoaminergic neurons of both human and monkey brain.
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Affiliation(s)
- T P Bonnert
- Neuroscience Research Centre, Merck Sharp and Dohme Research Laboratories, Eastwick Road, Harlow, Essex CM20 2QR, England, UK
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22
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Lengeling A, Wiltshire T, Otmani C, Bućan M. A Sequence-Ready BAC Contig of the GABA A Receptor Gene Cluster Gabrg1–Gabra2–Gabrb1 on Mouse Chromosome 5. Genome Res 1999. [DOI: 10.1101/gr.9.8.732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The type-A receptors for the neurotransmitter GABA (γ-aminobutyric acid) are ligand-gated chloride channels that mediate postsynaptic inhibition. The functional diversity of these receptors comes from the use of a large repertoire of subunits encoded by separate genes, as well as from differences in subunit composition of individual receptors. In mammals, a majority of GABAAreceptor subunit genes are located in gene clusters that may be important for their regulated expression and function. We have established a high-resolution physical map of the cluster of genes encoding GABAA receptor subunits α2 (Gabra2), β1 (Gabrb1), and γ1 (Gabrg1) on mouse chromosome 5. Rat cDNA probes and specific sequence probes for all three GABAA receptor subunit genes have been used to initiate the construction of a sequence-ready contig of bacterial artificial chromosomes (BACs) encompassing this cluster. In the process of contig construction clones from 129/Sv and C57BL/6J BAC libraries were isolated. The assembled 1.3-Mb contig, consisting of 45 BACs, gives five- to sixfold coverage over the gene cluster and provides an average resolution of one marker every 32 kb. A number of BAC insert ends were sequenced, generating 30 new sequence tag sites (STS) in addition to 6 Gabr gene-based and 3 expressed sequence tag (EST)-based markers. STSs from, and surrounding, theGabrg1–Gabra2–Gabrb1 gene cluster were mapped in the T31 mouse radiation hybrid panel. The integration of the BAC contig with a map of loci ordered by radiation hybrid mapping suggested the most likely genomic orientation of this cluster on mouse chromosome 5: cen–D5Mit151–Gabrg1–Gabra2–Gabrb1–D5Mit58–tel. This established contig will serve as a template for genomic sequencing and for functional analysis of the GABAA gene cluster on mouse chromosome 5 and the corresponding region on human chromosome 4.The sequence data described in this paper have been submitted to the GenBank/GSS data libraries under accession nos.AF156490 and AQ589406–AQ589436.
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23
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Liu XY, Dangel AW, Kelley RI, Zhao W, Denny P, Botcherby M, Cattanach B, Peters J, Hunsicker PR, Mallon AM, Strivens MA, Bate R, Miller W, Rhodes M, Brown SD, Herman GE. The gene mutated in bare patches and striated mice encodes a novel 3beta-hydroxysteroid dehydrogenase. Nat Genet 1999; 22:182-7. [PMID: 10369263 DOI: 10.1038/9700] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
X-linked dominant disorders that are exclusively lethal prenatally in hemizygous males have been described in human and mouse. None of the genes responsible has been isolated in either species. The bare patches (Bpa) and striated (Str) mouse mutations were originally identified in female offspring of X-irradiated males. Subsequently, additional independent alleles were described. We have previously mapped these X-linked dominant, male-lethal mutations to an overlapping region of 600 kb that is homologous to human Xq28 (ref. 4) and identified several candidate genes in this interval. Here we report mutations in one of these genes, Nsdhl, encoding an NAD(P)H steroid dehydrogenase-like protein, in two independent Bpa and three independent Str alleles. Quantitative analysis of sterols from tissues of affected Bpa mice support a role for Nsdhl in cholesterol biosynthesis. Our results demonstrate that Bpa and Str are allelic mutations and identify the first mammalian locus associated with an X-linked dominant, male-lethal phenotype. They also expand the spectrum of phenotypes associated with abnormalities of cholesterol metabolism.
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Affiliation(s)
- X Y Liu
- Children's Hospital Research Foundation and Department of Pediatrics, The Ohio State University, Columbus 43205, USA
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24
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Abstract
Until 1987, when the first GABA-A receptor subunit cDNAs were cloned and sequenced, it was thought that there were perhaps two subtypes of receptor in the brain. These were defined by the fact that benzodiazepines, which act through the GABA-A receptor, had two binding sites with different affinities. By 1991 it was known that the GABA-A receptor family existed as a family of subunits which coassembled to form a family of receptor subtypes in the brain. More recently, two additional GABA-A receptor subunits have been identified, epsilon and theta. The identification of these new members of the gene family, and the characterisation of the receptor subtypes into which they are incorporated, is reviewed.
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Affiliation(s)
- P J Whiting
- Neuroscience Research Centre, Merck Sharp & Dohme Research Laboratories, Harlow, Essex, UK.
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25
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Whiting PJ, Bonnert TP, McKernan RM, Farrar S, Le Bourdellès B, Heavens RP, Smith DW, Hewson L, Rigby MR, Sirinathsinghji DJ, Thompson SA, Wafford KA. Molecular and functional diversity of the expanding GABA-A receptor gene family. Ann N Y Acad Sci 1999; 868:645-53. [PMID: 10414349 DOI: 10.1111/j.1749-6632.1999.tb11341.x] [Citation(s) in RCA: 247] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fast inhibitory neurotransmission in the mammalian CNS is mediated primarily by the neurotransmitter gamma-aminobutyric acid (GABA), which, upon binding to its receptor, leads to opening of the intrinsic ion channel, allowing chloride to enter the cell. Over the past 10 years it has become clear that a family of GABA-A receptor subtypes exists, generated through the coassembly of polypeptides selected from alpha 1-alpha 6, beta 1-beta 3, gamma 1-gamma 3, delta, epsilon, and pie to form what is most likely a pentomeric macromolecule. The gene transcripts, and indeed the polypeptides, show distinct patterns of temporal and spatial expression, such that the GABA-A receptor subtypes have a defined localization that presumably reflects their physiological role. A picture is beginning to emerge of the properties conferred to receptor subtypes by the different subunits; these include different functional properties, differential modulation by protein kinases, and the targeting to different membrane compartments. These properties presumably underlie the different physiological roles of the various receptor subtypes. Recently we have identified a further member of the GABA-A receptor gene family, which we have termed theta, which appears to be most closely related to the beta subunits. The structure, function, and distribution of theta-containing receptors, and receptors containing the recently reported epsilon subunit, are described.
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Affiliation(s)
- P J Whiting
- Neuroscience Research Centre, Merck Sharp & Dohme Research Laboratories, Harlow, Essex, England, UK.
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26
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Abstract
The lens plays an essential role for proper eye development. Mouse mutants affecting lens development are excellent models for corresponding human disorders. Moreover, using mutations in particular genes the process of eye and lens development can be dissected into distinct steps. Therefore, three mouse mutants will be described in detail and discussed affecting three essential stages: formation of the lens vesicle, initiation of secondary lens fiber cell formation, and terminal differentiation of the secondary fiber cells. The mutant aphakia (ak) has been characterized by bilaterally apakic eyes [Varnum and Stevens (1968) J. Hered. 59, 147-150], and the corresponding gene was mapped to chromosome 19 [Varnum and Stevens (1975) Mouse News Letters 53, 35]. Recent investigations in our laboratory refined the linkage 0.6 +/- 0.3 N cm proximal to the microsatellite marker D19Mit10. The linked gene Pax2, responsible for proper development of the posterior part of the eye and the optic nerve, was excluded as candidate gene by sequence analysis. Histological analysis of the homozygous ak mutants revealed a persisting lens stalk and subsequently the formation of lens rudiments. The lens defects led to irregular iris development and retinal folding. Congenital aphakia is known as a rare human anomaly. Besides a corneal dystrophy (CDTB), no corresponding disease is localized at the homologous region of human chromosome 10q23. The Cat3 mutations are characterized by vacuolated lenses caused by alterations in the beginning of secondary lens fiber cell differentiation at embryonic day 12.5. Secondary malformations develop at the cornea and the iris, but the retina remains unaffected. Two mutant alleles of the Cat3 locus have been mapped to mouse chromosome 10 very close to the microsatellite markers D10Mit41 and D10Mit95 (less than 0.3 cM). Since Cat3 is mapped to a position, which is homologous to human chromosome 12q21-24, the disorder cornea plana congenita can be considered as a candidate disease. The series of Cat2 mutations have been mapped close to the locus encoding the gamma-crystallin gene cluster Cryg [Löster et al. (1994) Genomics 23, 240-242]. The Cat2nop mutation is characterized by a deletion of 11 bp and an insertion of 4 bp in the 3rd exon of Crygh leading to a truncated gamma B-crystallin. The defect in the Crygh gene is causative for the stop of lens fiber cell differentiation from embryonic day 15.5 onward. Besides the lens, no further ocular tissue is affected. The Cat2 mouse mutants are interesting models for human cataracts caused by mutations in the gamma-crystallin genes at human chromosome 2q32-35. The ak, Cat3 and Cat2 mutants are discussed in the context of other mutants affecting early eye and lens development. Additionally, human congenital cataracts are discussed, which have been characterized similar to the mouse models. The overview of the three types of mutants demonstrates that genes, which affect the early eye development, e.g. at the lens vesicle stage, have consequences for the development of the whole eye. In contrast, if the mutation influences later steps of lens differentiation, the consequences are restricted to the lens only. These data indicate a decreasing effect of the lens for the regulation of eye development during embryogenesis.
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Affiliation(s)
- J Graw
- GSF-National Research Center for Environment and Health, Institute of Mammalian Genetics, Neuherberg, Germany
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27
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Abstract
Nowhere is the record of receptor evolution more accessible than in the organization of the 19 vertebrate genes coding for subunits of the major inhibitory neurotransmitter receptor in the central nervous system, the gamma-aminobutyric acid receptor (GABAAR). Co-expression of alpha, beta, and gamma subunit genes is necessary for the formation of a GABAAR that is potentiated by widely used anxiolytics, anticonvulsants, and hypnotics. The identification of alpha, beta, and gamma genes on chromosomes 4, 5, and 15 suggests that co-localization of a gamma gene with an alpha and beta may be important for brain function. We have now directly examined the organization of GABAAR subunit genes on human chromosomes. Estimates of physical distance using in situ hybridization to cells in interphase, and gene localization using hybridization to cells in metaphase demonstrate the existence of beta-alpha-alpha-gamma gene clusters in cytogenetic bands on chromosomes 4(p12) and 5(q34). Sequencing of PAC clones establishes intercluster conservation of a unique head-to-head configuration for alpha and beta genes on chromosomes 4, 5, and 15. Remarkably, phylogenetic tree analysis predicts the existence of a beta-alpha-gamma ancestral gene cluster in which internal duplication of an ancestral alpha was followed by cluster duplication, resulting in the relative chromosomal positions of modern GABAAR subunit genes in the human genome.
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Affiliation(s)
- S J Russek
- Laboratory of Molecular Neurobiology, Department of Pharmacology, 80 East Concord Street, Boston University School of Medicine, Boston MA 02118, USA.
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28
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Abstract
X-linked dominant chondrodysplasia punctata is characterised by resolving irregular punctate calcifications of epiphyses, variable ichthyosis and atrophoderma, short stature, and cataracts. We report on a patient with this syndrome who had transiently abnormal peroxisomal function tests. We review the literature and propose that X-linked dominant chondrodysplasia punctata is a peroxisomal disorder and that its phenotype can be explained by X chromosome lyonisation and the relative proliferation of cells expressing the normal X allele.
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Affiliation(s)
- C J Wilson
- Department of Clinical Genetics, Starship Children's Hospital, Auckland, New Zealand
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29
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Abstract
This review is intended to provide an overview of techniques and a source of reagents for physical mapping of the mouse genome. It focuses on those applications, methods, or resources unique to the mouse and on the generation of comparative physical maps. The reference list is not comprehensive; rather, recent reviews on each topic and selected representative examples are given.
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Affiliation(s)
- G E Herman
- Department of Pediatrics, Ohio State University, Columbus, USA
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30
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Wilke K, Gaul R, Klauck SM, Poustka A. A gene in human chromosome band Xq28 (GABRE) defines a putative new subunit class of the GABAA neurotransmitter receptor. Genomics 1997; 45:1-10. [PMID: 9339354 DOI: 10.1006/geno.1997.4885] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have isolated and sequenced a novel human gene (GABRE) of the GABAA neurotransmitter receptor family. A cDNA sequence of the gene coding for a 506 amino acid protein was identified, representing a member of a putative new class (epsilon) of the GABAA receptor. The gene is transcribed at least at low level in several different tissues, with the highest levels being detected in adult heart and placenta. Alternative splicing of GABRE transcripts isolated from different tissues was observed at multiple positions of the gene, yielding an unusually complex variety of cDNA variants. The structure of the 5' region of most cDNAs is compatible with expression of protein sequence epsilon only in adult brain, whereas in other tissues, the majority of transcripts code for truncated protein sequences. The GABRE gene extends over 14 kb and is clustered together with the alpha 3 and the putative beta 4 GABAA receptor subunit genes in an approximately 0.8-Mb interval in chromosome band Xq28, located in the candidate regions of two different neurologic diseases. Based on features of conservation of protein sequences, gene structure, and genomic organization of GABAA receptor gene clusters, we propose that the epsilon and gamma subunit genes have a common ancestor and that GABAA receptor gene clusters in the human genome have diverged by multiple duplication events of an ancestral gene cluster containing one each alpha, beta, and gamma/epsilon precursor gene.
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Affiliation(s)
- K Wilke
- Deutsches Krebsforschungszentrum, Abteilung Molekulare Genomanalyse, Heidelberg, Germany
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31
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Heiss NS, Gloeckner G, Bächner D, Kioschis P, Klauck SM, Hinzmann B, Rosenthal A, Herman GE, Poustka A. Genomic structure of a novel LIM domain gene (ZNF185) in Xq28 and comparisons with the orthologous murine transcript. Genomics 1997; 43:329-38. [PMID: 9268636 DOI: 10.1006/geno.1997.4810] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Construction of a transcript map in the DXS52 region in Xq28 had previously led to the isolation of a cDNA with a LIM zinc finger domain in the carboxyl terminus. In parallel, the orthologous murine transcript was isolated from the syntenic region. The human and mouse cDNAs have been designated ZNF185 and Zfp185, respectively. By integrating the cDNA sequence with the cosmid-derived genomic sequence the exon-intron structure of the 3' end of the ZNF185 gene was resolved. Comparative sequence analyses of the human genomic sequence with the full-length murine cDNA facilitated prediction of the 5' end of the gene. The selective expression of three transcripts corresponding to the ZNF185 gene and a related gene was shown by Northern and Southern blots. In situ hybridizations revealed a nonubiquitous and stage-specific expression of Zfp185, especially in differentiating connective tissue. Since LIM proteins regulate cellular proliferation and/or differentiation by diverse mechanisms, and some have directly been associated with disease, conceivably ZNF185 may represent a candidate for a disease-causing gene linked to Xq28. Knowledge of the genomic structure will permit detailed mutation analyses.
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Affiliation(s)
- N S Heiss
- Department of Molecular Genome Analysis, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
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