| 1. |
- Alfonso, Julieta, et al.
(författare)
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Analysis of gene expression in the rat hippocampus using Real Time PCR reveals high inter-individual variation in mRNA expression levels
- 2002
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Ingår i: Journal of Neuroscience Research. - : Wiley. - 0360-4012 .- 1097-4547. ; 67:2, s. 225-34
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Tidskriftsartikel (refereegranskat)abstract
- In mammals, gene transcription is a step subjected to tight regulation mechanisms. In fact, changes in mRNA levels in the central nervous system (CNS) can account for numerous phenotypic differences in brain function. We performed a high-resolution analysis of mRNA expression levels for 37 genes selected from a normal rat hippocampus cDNA library. mRNA amounts were quantified using a Real Time PCR SYBR Green assay. We found that, in general, individuals from an inbred rat population (n = 20) have shown 2-3 times differences in the basal level of expression of the genes analyzed. Up to several fold differences among individuals were observed for certain genes. These inter-individual differences were obtained after correction for the different amounts of mRNA in each sample. Power calculations were performed to determine the number of individuals required to detect reliable differences in expression levels between a control and an experimental group. These data indicated that, depending on the variability of the candidate gene selected, it was necessary to analyze from five to 135 individuals in each group to detect differences of 50% in the levels of mRNA expression between two groups investigated. The comparison of mRNA abundance from different genes revealed a wide range of expression levels for the 37 genes, showing a 26,000-fold difference between the highest and lowest expressed gene.
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| 2. |
- Balciuniene, Jorune, et al.
(författare)
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Alpha-tectorin involvement in hearing disabilities : One gene-two phenotypes
- 1999
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Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 105:3, s. 211-216
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Tidskriftsartikel (refereegranskat)abstract
- The human alpha-tectorin (TECTA) gene has recently been cloned and proposed to be involved in autosomal dominant non-syndromic hearing impairment (NSHI) in two families linked to the DFNA12 locus. We have studied a Swedish pedigree with autosomal dominant NSHI with possible digenic inheritance of the disease, involving locus DFNA12 in chromosome 11 and locus DFNA2 in chromosome 1. Mutation analysis of the TECTA gene in this family has identified eight nucleotide substitutions indicating that TECTA is highly polymorphic. One of the changes results in a cysteine to serine (C 1057 S) mutation, in the zonadhesin domain of TECTA; this segregates with the disease haplotype on chromosome 11 and is not present in a control population. The mutation results in the replacement of a cysteine in one of the repeats of the zonadhesin/Von Willebrand domain of the protein and might cause a change in the crosslinking of the polypeptide. These findings add support to the involvement of TECTA in hearing disabilities. However, the three families carrying different TECTA mutations also show phenotypic differences: the hearing loss ranges from prelingual to progressive with late onset. The explanation for the different phenotypes and some clues regarding the functions of TECTA may lie in the localization of the mutations in the different modules of the protein. Another possibility is that the phenotype in the Swedish family is the result of two defective genes.
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| 3. |
- Balciuniene, Jorune, et al.
(författare)
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Evidence for digenic inheritance of nonsyndromic hereditary hearing loss in a Swedish family
- 1998
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 63:3, s. 786-93
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Tidskriftsartikel (refereegranskat)abstract
- We investigated a Swedish family with nonsyndromic progressive bilateral sensorineural hearing loss. Thirteen candidate loci for autosomal dominant nonsyndromic hearing loss were tested for linkage in this family. We found significant LOD scores (>3) for markers at candidate locus DFNA12 (11q22-q24) and suggestive LOD scores (>2) for markers at locus DFNA2 (1p32). Our results for markers on chromosome 11 narrowed down the candidate region for the DFNA12 locus. A detailed analysis of the phenotypes and haplotypes shared by the affected individuals supported the notion that two genes segregated together with hearing impairment in the family. Severely affected family members had haplotypes linked to the disease allele on both chromosomes 1 and 11, whereas individuals with milder hearing loss had haplotypes linked to the disease allele on either chromosome 1 or chromosome 11. These observations suggest an additive effect of two genes, each gene resulting in a mild and sometimes undiagnosed phenotype, but both together resulting in a more severe phenotype.
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| 4. |
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| 5. |
- Björnerfeldt, Susanne, 1975-
(författare)
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Consequences of the Domestication of Man’s Best Friend, The Dog
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The dog was the first animal to be domesticated and the process started at least 15 000 years ago. Today it is the most morphologically diverse mammal, with a huge variation in size and shape. Dogs have always been useful to humans in several ways, from being a food source, hunting companion, guard, social companion and lately also a model for scientific research. This thesis describes some of the changes that have occurred in the dog’s genome, both during the domestication process and later through breed creation. To give a more comprehensive view, three genetic systems were studied: maternally inherited mitochondrial DNA, paternally inherited Y chromosome and biparental autosomal chromosomes. I also sequenced complete mitochondrial genomes to view the effect new living conditions might have had on dogs’ genes after domestication. Finally, knowledge of the genetic structure in purebred dogs was used to test analytic methods usable in other species or in natural populations where little information is available. The domestication process appears to have caused a relaxation of the selective constraint in the mitochondrial genome, leading to a faster rate of accumulation of nonsynonymous changes in the mitochondrial genes. Later, the process of breed creation resulted in genetically separated breed groups. Breeds are a result from an unequal contribution of males and females with only a few popular sires contributing and a larger amount of dams. However, modern breeder preferences might lead to disruptive selective forces within breeds, which can result in additional fragmentation of breeds. The increase in linkage disequilibrium that this represents increases the value of purebred dogs as model organisms for the identification and mapping of diseases and traits. Purebred dogs’ potential for these kinds of studies will probably increase the more we know about the dog’s genome.
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| 6. |
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| 7. |
- Castensson, Anja, et al.
(författare)
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Decrease of serotonin receptor 2C in schizophrenia brains identified by high-resolution mRNA expression analysis
- 2003
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Ingår i: Biological Psychiatry. - 0006-3223 .- 1873-2402. ; 54:11, s. 1212-1221
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: RNA expression profiling can provide hints for the selection of candidate susceptibility genes, for formulation of hypotheses about the development of a disease, and/or for selection of candidate gene targets for novel drug development. We measured messenger RNA expression levels of 16 candidate genes in brain samples from 55 schizophrenia patients and 55 controls. This is the largest sample so far used to identify genes differentially expressed in schizophrenia brains. METHODS: We used a sensitive real-time polymerase chain reaction methodology and a novel statistical approach, including the development of a linear model of analysis of covariance type. RESULTS: We found two genes differentially expressed: monoamine oxidase B was significantly increased in schizophrenia brain (p =.001), whereas one of the serotonin receptor genes, serotonin receptor 2C, was significantly decreased (p =.001). Other genes, previously proposed to be differentially expressed in schizophrenia brain, were invariant in our analysis. CONCLUSIONS:The differential expression of serotonin receptor 2C is particularly relevant for the development of new atypical antipsychotic drugs. The strategy presented here is useful to evaluate hypothesizes for the development of the disease proposed by other investigators.
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| 8. |
- Castensson, Anja, et al.
(författare)
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Decrease of serotonin receptor 2C in schizophrenia brains identified by high-resolution mRNA expression analysis
- 2003
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Ingår i: Biological Psychiatry. - : Elsevier BV. - 0006-3223 .- 1873-2402. ; 54:11, s. 1212-1221
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Tidskriftsartikel (refereegranskat)abstract
- Background: RNA expression profiling can provide hints for the selection of candidate susceptibility genes, for formulation of hypotheses about the development of a disease, and/or for selection of candidate gene targets for novel drug development. We measured messenger RNA expression levels of 16 candidate genes in brain samples from 55 schizophrenia patients and 55 controls. This is the largest sample so far used to identify genes differentially expressed in schizophrenia brains.Methods: We used a sensitive real-time polymerase chain reaction methodology and a novel statistical approach, including the development of a linear model of analysis of covariance type.Results: We found two genes differentially expressed: monoamine oxidase B was significantly increased in schizophrenia brain (p = .001), whereas one of the serotonin receptor genes, serotonin receptor 2C, was significantly decreased (p = .001). Other genes, previously proposed to be differentially expressed in schizophrenia brain, were invariant in our analysis.Conclusions: The differential expression of serotonin receptor 2C is particularly relevant for the development of new atypical antipsychotic drugs. The strategy presented here is useful to evaluate hypothesizes for the development of the disease proposed by other investigators.
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| 9. |
- Castensson, Anja, et al.
(författare)
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High-resolution quantification of specific mRNA levels in human brain autopsies and biopsies
- 2000
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Ingår i: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051 .- 1549-5469. ; 10:8, s. 1219-29
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Tidskriftsartikel (refereegranskat)abstract
- Quantification of mRNA levels in human cortical brain biopsies and autopsies was performed using a fluorogenic 5' nuclease assay. The reproducibility of the assay using replica plates was 97%-99%. Relative quantities of mRNA from 16 different genes were evaluated using a statistical approach based on ANCOVA analysis. Comparison of the relative mRNA levels between two groups of samples with different time postmortem revealed unchanged relative expression levels for most genes. Only CYP26A1 mRNA levels showed a significant decrease with prolonged time postmortem (p = 0.00004). Also, there was a general decrease in measured mRNA levels for all genes in autopsies compared to biopsies; however, on comparing mRNA levels after adjusting with reference genes, no significant differences were found between mRNA levels in autopsies and biopsies. This observation indicates that studies of postmortem material can be performed to reveal the relative in vivo mRNA levels of genes. Power calculations were done to determine the number of individuals necessary to detect differences in mRNA levels of 1.5-fold to tenfold using the strategy described here. This analysis showed that samples from at least 50 individuals per group, patients and controls, are required for high-resolution ( approximately twofold changes) differential expression screenings in the human brain. Experiments done on ten individuals per group will result in a resolution of approximately fivefold changes in expression levels. In general, the sensitivity and resolution of any differential expression study will depend on the sample size used and the between-individual variability of the genes analyzed.
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| 10. |
- Castensson, Anja, 1971-
(författare)
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High-resolution Studies of mRNA Expression in Brain : A Search for Genes Differently Expressed in Schizophrenia
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Gene expression differences between patients and controls can be used to find susceptibility genes and drug targets for a disease. High-resolution strategies are required because the differences between the investigated groups may be small and numerous factors may affect the mRNA quantity. This thesis is based on the use of real-time RT-PCR combined with a new statistical approach, developed to detect small differences between patients and controls and differences due to patient subgroups. Comparisons between human brain biopsy and autopsy samples showed that post-mortem tissue can be used to make conclusions on the relative mRNA levels in the living brain. Power analysis based on human brain mRNA expression from 14 genes adjusted with two reference genes, revealed that a sample size of 50 patients and 50 controls was required to detect a 2-fold difference with a power and a confidence of 95%. A similar study in rats revealed that approximately the same sample size was required for rat brain mRNA expression studies. The mRNA levels of several genes were studied in 55 schizophrenia and 55 control prefrontal brain autopsies, using a novel and more powerful statistical analysis. The serotonin receptor 2C gene (HTR2C) showed a significant 1.5-fold decrease in the patients as compared to controls, and the monoamine oxidase B gene (MAOB) a 1.2-fold increase. The mechanism behind the decrease of HTR2C mRNA levels was investigated by studying the correlation of drug treatment and HTR2C promoter polymorphisms to the HTR2C expression levels. The observed decrease was present in untreated patients, suggesting that the HTR2C mRNA decrease is correlated with the disease and not the treatment. There was no association between promoter polymorphisms and HTR2C expression levels. Thus, the molecular mechanism for the decreased expression remains unclear. Nevertheless, the results support a role for monoaminergic synapses in schizophrenia.
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| 11. |
- Castensson, Anja, et al.
(författare)
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Serotonin Receptor 2C (HTR2C) and Schizophrenia : Examination of Possible Medication and Genetic Influences on Expression Levels
- 2005
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Ingår i: American Journal of Medical Genetics. - : Wiley. - 0148-7299 .- 1096-8628. ; 134B, s. 84-89
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Tidskriftsartikel (refereegranskat)abstract
- The serotonin receptor 2C (HTR2C) gene is of interest in schizophrenia due to its involvement in regulation of dopamine activity in the prefrontal cortex. We have previously reported a decreased expression of HTR2C mRNA levels in the prefrontal cortex of schizophrenia patients. The variability in mRNA expression levels is evaluated here more closely in relation to promoter haplotypes and neuroleptic treatment received by the patients. The decrease in HTR2C mRNA was present in neuroleptic treated individuals and in patients untreated at death, indicating that the lower expression is not a short-term medication effect. Three promoter polymorphisms were used to construct haplotypes. No SNP displayed genotypic or haplotypic association with the disease. Gene expression of HTR2C was not affected by haplotype and the expression decrease in schizophrenia patients was similar in all haplotype combinations (diplotypes). We conclude that the decrease in HTR2C expression in schizophrenia may be related to the disease mechanism rather than to drug treatment. The disease related changes in HTR2C expression are not related to the promoter variants typed in our sample, but could be due to other regulatory variants or trans-acting factors.
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| 12. |
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| 13. |
- Cavelier, L, et al.
(författare)
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MtDNA mutations in maternally inherited diabetes : presence of the 3397 ND1 mutation previously associated with Alzheimer's and Parkinson's disease
- 2001
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Ingår i: Hereditas. - : Springer Science and Business Media LLC. - 0018-0661 .- 1601-5223. ; 135:1, s. 65-70
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Tidskriftsartikel (refereegranskat)abstract
- Mutations in the mitochondrial tRNA(leu) (UUR) gene have been associated with diabetes mellitus and deafness. We screened for the presence of mtDNA mutations in the tRNA(leu) (UUR) gene and adjacent ND1 sequences in 12 diabetes mellitus pedigrees with a possible maternal inheritance of the disease. One patient carried a G to A substitution at nt 3243 (tRNA(leu) (UUR) gene) in heteroplasmic state. In a second pedigree a patient had an A to G substitution at nt 3397 in the ND1 gene. All maternal relatives of the proband had the 3397 substitution in homoplasmic state. This substitution was not present in 246 nonsymptomatic Caucasian controls. The 3397 substitution changes a highly conserved methionine to a valine at aa 31 and has previously been found in Alzheimer's (AD) and Parkinson's (PD) disease patients. Substitutions in the mitochondrial ND1 gene at aa 30 and 31 have associated with a number of different diseases (e.g. AD/PD, MELAS, cardiomyopathy and diabetes mellitus, LHON, Wolfram-syndrome and maternal inherited diabetes) suggesting that changes at these two codons may be associated with very diverse pathogenic processes. In a further attempt to search for mtDNA mutations outside the tRNAleu gene associated with diabetes, the whole mtDNA genome sequence was determined for two patients with maternally inherited diabetes and deafness. Except for substitutions previously reported as polymorphisms, none of the two patients showed any non-synonymous substitutions either in homoplasmic or heteroplasmic state. These results imply that the maternal inherited diabetes and deafness in these patients must result from alterations of nuclear genes and/or environmental factors.
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| 14. |
- Cavelier, Lucia, et al.
(författare)
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MtDNA substitution rate and segregation of heteroplasmy in coding andnoncoding regions
- 2000
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Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 107:1, s. 45-50
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Tidskriftsartikel (refereegranskat)abstract
- The mitochondrial DNA (mtDNA) substitution rate and segregation of heteroplasmy were studied for the non-coding control region (D-loop) and 500 bp of the coding region between nucleotide positions 5550 and 6050, by sequence analysis of blood samples from 194 individuals, representing 33 maternal lineages. No homoplasmic nucleotide substitutions were detected in a total of 292 transmissions. The estimated substitution rate per nucleotide per million years for the control region (micro>0.21, 95% CI 0-0.6) was not significantly different from that for the coding region (micro>0.54, 95% CI 0-1.0). Variation in the length of homopolymeric C streches was observed at three sites in the control region (positions 65, 309 and 16,189), all of which were in the heteroplasmic state. Segregation of heteroplasmic genotypes between generations was observed in several maternal pedigrees. At position 309, a longer poly C tract length was strongly associated with a higher probability for heteroplasmy and rapid segregation between generations. The length heteroplasmy at positions 65 and 16,189 was found at low frequency and was confined to a few families.
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| 15. |
- Emilsson, Lina, et al.
(författare)
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Alzheimer’s disease: mRNA expression profiles of multiple patients show alterations of genes involved with calcium signalling
- 2006
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Ingår i: Neurobiology of Disease. - : Elsevier BV. - 0969-9961 .- 1095-953X. ; 21:3, s. 618-625
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Tidskriftsartikel (refereegranskat)abstract
- We combined global and high-resolution strategies to find genes with altered mRNA expression levels in one of the largest collection of brain autopsies from Alzheimer's patients and controls ever studied. Our global analysis involved microarray hybridizations of large pools of samples obtained from 114 individuals, using two independent sets of microarrays. Ten genes selected from the microarray experiments were quantified on each individual separately using real-time RT-PCR. This high-resolution analysis accounted for systematic differences in age, postmortem interval, brain pH, and reference gene expression, and it estimated the effect of disease on mRNA levels, on top of the effect of all other variables. Differential expression was confirmed for eight out of ten genes. Among them, Type B inositol 1,4,5-trisphosphate 3-kinase (ITPKB), and regulator of G protein signaling 4 (RGS4) showed highly altered expression levels in patients (P values < 0.0001). Our results point towards increased inositol triphospate (IP3)-mediated calcium signaling in Alzheimer's disease.
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| 16. |
- Emilsson, Lina, 1973-
(författare)
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Detection of Differentially Expressed Genes in Alzheimer's Disease : Regulator of G-protein Signalling 4: A Novel Mediator of APP Processing
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Alzheimer’s disease is a neurodegenerative disease characterised by progressive memory deterioration and cognitive impairment. Pathological hallmarks are extracellular senile plaques, neurofibrillary tangles and neuron loss. Senile plaques are produced through altered processing of the membrane-bound protein APP. Different neurotransmitter signal transduction pathways have been implicated in the formation or development of Alzheimer’s pathologies, but the molecular mechanisms behind these changes are not well known. The overall aims of this thesis were to identify novel genes with differential expression in Alzheimer’s disease and to investigate mechanisms initiating these changes and their relationship to the disease. A real-time RT-PCR strategy was developed to enable detection of small mRNA changes in human brain autopsy samples. This approach was first used to investigate levels of expression of a candidate gene (MAO), and later employed to verify gene expression differences detected by cDNA microarray analysis. Of several genes verified as differentially expressed in the patients, ITPKB (Inositol 1,4,5-trisphosphate 3-kinase B) and RGS4 (Regulator of G-protein signalling 4) presented the largest expression differences in Alzheimer’s cases compared to control samples. Several splice variants of RGS4 showed similar down-regulation levels and one rare haplotype was associated with decreased RGS4 expression. Functional studies in SH-SY5Y cell cultures overexpressing RGS4 showed that it is likely that RGS4 affects APP processing by regulating PRKC expression levels. The combined expression of RGS4 and ITPKB is for the first time presented in this thesis as genes with altered mRNA levels in Alzheimer’s disease. These two genes are implicated in the same signalling pathway that modifies calcium levels in the cell. Furthermore, the fact that RGS4 affects APP processing suggests that RGS4 is involved in the development of senile plaques. This motivates further functional studies of this gene and suggests that RGS4 may become a new potential drug target for Alzheimer’s disease.
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| 17. |
- Emilsson, Lina, et al.
(författare)
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Increased monoamine oxidase messenger RNA expression levels in frontal cortex of Alzheimer's disease patients
- 2002
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Ingår i: Neuroscience Letters. - 0304-3940 .- 1872-7972. ; 326:1, s. 56-60.
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Tidskriftsartikel (refereegranskat)abstract
- Alzheimer's disease (AD) is a neurodegenerative disorder and the most common cause of dementia in the industrialised world. The two monoamine oxidase (MAO) enzymes, monoamine oxidase A (MAOA) and monoamine oxidase B (MAOB), are important in the metabolism of monoamine neurotransmitters. AD and ageing have been shown to increase enzyme activity for both MAOA and MAOB. An increase (rather than decrease) of enzyme activity is a rare event in a disease that results in a decrease in the number of cells in the brain. The mechanism, transcriptional or post-transcriptional, responsible for the increase in protein activity, is not known. In this study, we investigate for the first time the messenger RNA (mRNA) expression levels of both MAOA and MAOB in 246 cortical brain samples obtained at autopsy from 62 AD patients and 61 normal controls. We found a significant increase in mRNA levels for both MAOA (P=0.001) and MAOB (P=0.002) in disease brain tissue. This indicates that both MAO enzymes might be important in the progression of AD.
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| 18. |
- Emilsson, Lina, et al.
(författare)
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Low mRNA levels of RGS4 splice variants in Alzheimer’s disease and association between a rare haplotype and decreased mRNA expression
- 2006
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Ingår i: Synapse. - 0887-4476 .- 1098-2396. ; 59:3, s. 173-176
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Tidskriftsartikel (refereegranskat)abstract
- Regulator of G-protein signaling 4 (RGS4) showed decreased mRNAlevels in Alzheimer’s disease in a large collection of human brain autopsies from prefrontalcortex. The expression levels of three RGS4 splice variants were examined inthe same samples, and the association between RGS4 gene expression and/or the diseasewith single nucleotide polymorphisms located in this gene was explored. We showthat all splice variants are down-regulated in patients. We also demonstrate that onerare haplotype (ATAG) is associated with decreased mRNA levels in both cases andcontrols. Our results suggest that an altered regulation in transcription initiation maybe an important mechanism for low RGS4 protein levels in Alzeimer’s disease.
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| 19. |
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| 20. |
- Farnsworth, Bryn, et al.
(författare)
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Gene Expression of Quaking in Sporadic Alzheimer’s Disease Patients is Both Upregulated and Related to Expression Levels of Genes Involved in Amyloid Plaque and Neurofibrillary Tangle Formation
- 2016
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 53:1, s. 209-219
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Tidskriftsartikel (refereegranskat)abstract
- Quaking (QKI) is a gene exclusively expressed within glial cells. QKI has previously been implicated in various neurological disorders and diseases, including Alzheimer’s disease (AD), a condition for which increasing evidence suggests a central role of glia cells. The objective of the present study was to investigate the expression levels of QKI and three QKI isoforms (QKI5, QKI6, and QKI7) in AD. Genes that have previously been related to the ontogeny and progression of AD, specifically APP, PSEN1, PSEN2, and MAPT, were also investigated. A real-time PCR assay of 123 samples from human postmortem sporadic AD patients and control brains was performed. The expression values were analyzed with an analysis of covariance model and subsequent multiple regressions to explore the possibility of related expression values between QKI, QKI isoforms, and AD-related genes. Further, the sequences of AD-related genes were analyzed for the presence of QKI binding domains. QKI and all measured QKI isoforms were found to be significantly upregulated in AD samples, relative to control samples. However, APP, PSEN1, PSEN2, and MAPT were not found to be significantly different. QKI and QKI isoforms were found to be predictive for the variance of APP, PSEN1, PSEN2, and MAPT, and putative QKI binding sites suggests an interaction with QKI. Overall, these results implicate a possible role of QKI in AD, although the exact mechanism by which this occurs remains to be uncovered.
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| 21. |
- Farnsworth, Bryn, et al.
(författare)
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Morpholino knockdown of qkib leads to disturbed neural development in the larval zebrafish.
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Quaking (QKI) is a member of the Signal Transduction and Activation of RNA (STAR) protein family and has been found to regulate the splicing, quantity, and translation of mRNA. Several studies have also found an association of QKI with a variety of human neurological disorders, such as schizophrenia, ataxia, and Alzheimer’s disease, amongst others. Mouse mutants show clear developmental defects in myelin formation. Critical periods for the investigation of myelin aberration have been precluded by the embryonic lethality of Qk null mice mutants. We have previously shown that the zebrafish is a suitable tool in which to interrogate qki function. Within this study we employ a gene-knockdown approach with the use of morpholinos and the Tg(olig2:DsRed2), and Tg(-4.9sox10:eGFP) transgenic zebrafish lines, and confocal imaging. We find a reduction in the number of oligodendrocytes, critical for the formation of myelin. We also find aberrations in the development and arborization of motor neurons across the spinal cord, and a complete absence of eurydendroid cells within the cerebellum. These findings have parallels to both neuroanatomical evidence from viable Qk mutant mice, and to aspects of related human neurological disease.
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| 22. |
- Farnsworth, Bryn, et al.
(författare)
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QKI6B is upregulated in schizophrenic brains and predicts GFAP expression
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Ingår i: Schizophrenia Research. - 0920-9964 .- 1573-2509.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Schizophrenia is a highly heritable disorder with a heterogeneous symptomatology. Research increasingly indicates the importance of the crucial and often overlooked glial perturbations within schizophrenic brains. Within this study, we examined an isoform of quaking (gene encoding an RNA-binding protein that is exclusively expressed in glial cells), known as QKI6B, and an astrocyte marker glial fibrillary acidic protein (GFAP), postulated to be under the regulation of QKI. The expression levels of these genes were quantified across post-mortem samples from the prefrontal cortex of 55 schizophrenic brains, and 55 healthy control brains, using real-time PCR. We report, through an analysis of covariance (ANCOVA) model, an upregulation of both QKI6B, and GFAP in the prefrontal cortex of schizophrenic brains. Previous research has suggested that the QKI protein directly regulates the expression of several genes through interaction with a motif in the target’s sequence, termed the Quaking Response Element (QRE). We therefore examined if QKI6B expression can predict the outcome of GFAP, and several oligodendrocyte-related genes, using a multiple linear regression approach. We found that QKI6B significantly predicts, and possibly regulates the expression of GFAP, but does not predict oligodendrocyte-related gene outcome, as previously seen with other QKI isoforms.
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| 23. |
- Jazin, Elena, et al.
(författare)
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Sex differences in molecular neuroscience : from fruit flies to humans
- 2010
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Ingår i: Nature Reviews Neuroscience. - : Springer Science and Business Media LLC. - 1471-003X .- 1471-0048. ; 11:1, s. 9-17
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Forskningsöversikt (refereegranskat)abstract
- A plethora of discoveries relating to sex influences on brain function is rapidly moving this field into the spotlight for most areas of neuroscience. The domain of molecular or genetic neuroscience is no exception. The goal of this article is to highlight key developments concerning sex-based dimorphisms in molecular neuroscience, describe control mechanisms regulating these differences, address the implications of these dimorphisms for normal and abnormal brain function and discuss what these advances mean for future work in the field. The overriding conclusion is that, as for neuroscience in general, molecular neuroscience has to take into account potential sex influences that might modify signalling pathways.
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| 24. |
- Jazin, Elena, et al.
(författare)
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Trypanosoma cruzi exoantigen is a member of a 160 kDa gene family
- 1995
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Ingår i: Parasitology. - 0031-1820 .- 1469-8161. ; 110:Pt1, s. 61-69
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Tidskriftsartikel (refereegranskat)abstract
- During the chronic stage of Chagas disease a 160 kDa antigen appears in the blood of patients and remains detectable many years after the onset of the disease. This antigen is secreted by the trypomastigote form of the parasite while it is undetectable in the epimastigote form. We report here that the chronic 160 kDa exoantigen is encoded by a gene family (CEA 160 family). We describe the cloning and partial nucleotide sequence of a gene (CEA 160-1) belonging to the CEA160 family. Comparison of the gene sequence with other sequences present in the databases revealed homologies with several Trypanosoma cruzi surface antigens. Highest amino acid identity (59%) was with members of a family containing epitopes that mimic nervous tissues (Van Voorhis et al. 1993). Another related group (18-22% amino acid identity) comprises proteins of 85 or 160 kDa sharing an amino acid motif that is conserved among bacterial neuraminidases (Fouts et al. 1991; Pollevick et al. 1991; Kahn et al. 1991; Takle & Cross, 1991; Franco et al. 1993). The amino acid identities with the different antigens were not homogeneously distributed. Regions of higher identity (40-60%) were grouped in the central region of each protein.
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| 25. |
- Jiang, Lin, et al.
(författare)
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Haloperidol changes mRNA expression of a QKI splice variant in human astrocytoma cells.
- 2009
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Ingår i: BMC pharmacology. - : Springer Science and Business Media LLC. - 1471-2210. ; 9, s. 6-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The quaking homolog, KH domain RNA binding (mouse) (QKI) is a candidate gene for schizophrenia. Disturbed QKI mRNA expression is observed in the prefrontal cortex of patients, and some of these changes correlate to treatment with antipsychotic drugs.To test if low doses of antipsychotic drugs can modify QKI mRNA expression, human astrocytoma (U343) and oligodendroglioma (HOG) cell lines were treated with five different antipsychotic drugs including Haloperidol, Aripiprazole, Clozapine, Olanzapine and Risperidone. Messenger RNA expression levels of splice variants QKI-5, QKI-6 and QKI-7 were measured by Real-Time PCR. RESULTS: Haloperidol treatment (0.2 microM) doubled QKI-7 mRNA levels in U343 cells after 6 hours (p-value < 0.02). The effect was dose dependent, and cells treated with ten times higher concentration (2 microM) responded with a five-fold and three-fold increase in QKI-7, 6 and 24 hours after treatment, respectively (p-values < 0.0001). CONCLUSION: The results in U343 cells suggest that QKI-7 mRNA expression in human astrocytes is induced by Haloperidol, at concentrations similar to plasma levels relevant to clinical treatment of schizophrenia. The molecular mechanism of action of antipsychotic drugs after binding to receptors is not well known. We hypothesize that QKI regulation is involved in this mechanism.
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