• BMB Reports
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• v.30 no.1
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• pp.33-36
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• 1997

Age-dependent deletion of mitochondrial DNA (mtDNA) was detected in mouse brain using PCR method. The size of the deleted fragment was 0.5 kb, 0.9 kb. 1.7 kb and 4.3 kb in the region between cytochrome b gene and ATPase 6 gene. The deleted fragment was increased gradually from 3-month to 22month Direct repeat sequence flanking the deletion in 0.5 kb PCR product was TAAT.

• Journal of Life Science
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• v.9 no.1
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• pp.5-8
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• 1999

Helicobacter pylori is the etiologic agent of human gastritis and peptic ulceration and produces urease as the major protein component on its surface. H. pylori urease is known to serve as a major virulence factor and a potent immunogen. Deletion mutageneses were performed in the H. pylori urease accessory genes by using combinations of restriction enzymes and other DNA modifying enzymes in order to assess the function of these accessory gene products in the expression of the active urease. Selective disruptions in the accessory gene regions resulted in complete abolishment of the urease activity, which is consistent with other bacterial ureases. Interestingly, deletions in ureE-containing regions caused reduced expression of the structural enzyme subunits.

• Mycobiology
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• v.46 no.3
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• pp.236-241
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• 2018

The cation-dependent galactose-specific flocculation activity of the Schizosaccharomyces pombe null mutant of $lkh1^+$, the gene encoding LAMMER kinase homolog, has previously been reported by our group. Here, we show that disruption of $prk1^+$, another flocculation associated regulatory kinase encoding gene, also resulted in cation-dependent galactosespecific flocculation. Deletion of prk1 increased the flocculation phenotype of the $lkh1^+$ null mutant and its overexpression reversed the flocculation of cells caused by lkh1 deletion. Transcript levels of $prk1^+$ were also decreased by $lkh1^+$ deletion. Cumulatively, these results indicate that Lkh1 is one of the negative regulators acting upstream of Prk1, regulating non-sexual flocculation in fission yeast.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.14-17
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• 2001

Positional cloning (map-based cloning) of mutations or genetic variations has been served as an invaluable tool to understand in-vivo functions of genes and to identify molecular components underlying phenotypes of interest. Mice homozygous for the cerebellar deficient folia (cdf) mutation are ataxic, with cerebellar hypoplasia and abnormal lobulation of the cerebellum. In the cdf mutant cerebellum approximately 40% of Purkinje cells are ectopically located within the white matter and the inner granule cell layer (IGL). To identify the cdf gene, a high-resolution genetic map for the cdf-gene-encompassing region was constructed using 1997 F2 mice generated from C3H/HeSnJ-cdf/cdf and CAST/Ei intercross. The cdf gene showed complete linkage disequilibrium with three tightly linked markers D6Mit208, D6Mit359, and D6Mit225. A contig using YAC, BAC, and P1 clones was constructed for the cdf critical region to identify the gene. A deletion in the cdf critical region on chromosome 6 that removes approximately 150kb of DNA was identified. A gene associated with this deletion was identified using cDNA selection. cdf mutant mice with the transgenic copy of the identified gene restored the brain abnormalities of the mutant mice. The positional cloning of cdf gene provides a good example showing the identification of a gene could lead to finding a new component of important molecular pathways.

• Animal cells and systems
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• v.9 no.3
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• pp.107-111
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• 2005

C. elegans DLK-1 has been reported to play an important role in synaptogenesis by shaping the structure of presynaptic terminal. In this study, we investigated the expression pattern and regulation of the dlk-1 gene in C. elegans. To determine the expression pattern, we made a dlk-1::gfp fusion construct, named pPDdg1, which consisted of -2.2 kb 5' upstream region, the first exon, the first intron, and a part of the second exon of the dlk-1 gene. By microinjecting this construct into the worm, we observed that the DLK-1::GFP was expressed mainly in neurons. We next examined the regulatory elements of gene expression by deletion analysis of pPDdg1. Removal of a large portion of the 5' upstream region (${\Delta}-361$ to -2246) of the gene had little effect on the expression pattern, whereas deletion of the first intron led to elimination of the DLK-1::GFP expression in most of the neurons. Our results suggest that the first intron of the C. elegans dlk-1 gene contains the regulatory element critical for gene expression.

• Animal cells and systems
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• v.5 no.1
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• pp.65-69
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• 2001

Obtaining mutant animals is important for studying the function of a particular gene. A chemical mutagenesis was first carried out to generate mutations in C. elegans. In this study, we used ultraviolet-activated 4,5',8-trimethylpsoralen to induce small deletion mutations. A library of mutagenized worms was prepared for recovery of candidate animals and stored at $15^{\circ}C$ during screening instead of being made into a frozen stock library. In order to isolate deletion mutations in target genes, a polymerase chain reaction (PCR)-based screening method was used. As a result, two independent mutants with deletions of approximately 1.0 kb and 1.3 kb were isolated. This modified and improved reverse genetic approach was proven to be effective and practical for isolating mutant animals to study gene function at the organismal level.

• The Plant Pathology Journal
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• v.32 no.3
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• pp.173-181
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• 2016

Gene disruption by homologous recombination is widely used to investigate and analyze the function of genes in Fusarium fujikuroi, a fungus that causes bakanae disease and root rot symptoms in rice. To generate gene deletion constructs, the use of conventional cloning methods, which rely on restriction enzymes and ligases, has had limited success due to a lack of unique restriction enzyme sites. Although strategies that avoid the use of restriction enzymes have been employed to overcome this issue, these methods require complicated PCR steps or are frequently inefficient. Here, we introduce a cloning system that utilizes multi-fragment assembly by In-Fusion to generate a gene disruption construct. This method utilizes DNA fragment fusion and requires only one PCR step and one reaction for construction. Using this strategy, a gene disruption construct for Fusarium cyclin C1 (FCC1), which is associated with fumonisin B1 bio-synthesis, was successfully created and used for fungal transformation. In vivo and in vitro experiments using confirmed fcc1 mutants suggest that fumonisin production is closely related to disease symptoms exhibited by F. fujikuroi strain B14. Taken together, this multi-fragment assembly method represents a simpler and a more convenient process for targeted gene disruption in fungi.

• Journal of Genetic Medicine
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• v.13 no.1
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• pp.36-40
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• 2016

Tuberous sclerosis complex (TSC, MIM#191100) is an autosomal dominant neurocutaneous syndrome caused by mutation or deletion of TSC1 encoding hamartin or TSC2 encoding tuberin and characterized by seizure, mental retardation, and multiple hamartomas or benign tumors in the skin, brain, retina, heart, kidney, and lungs. The TSC2 gene on chromosome 16p13.3 lies adjacent to the PKD1 gene which is responsible for autosomal dominant polycystic kidney disease (MIM#173900). The TSC2/PKD1 contiguous gene syndrome (TSC2/PKD1 CGDS, MIM#600273) is caused by deletion of both TSC2 and PKD1 gene. We recently experienced a 15 month-old boy and a 26 month-old girl with TSC2/PKD1 CGDS confirmed by multiplex ligation-dependent probe amplification (MLPA) analysis. They showed not only typical neurologic manifestations of TSC such as epilepsy, subependymal nodules, and subcortical tubers, but also polycystic kidney disease. The contiguous gene syndrome involving PKD1 and TSC2 should be suspected in children with enlarged polycystic kidneys and TSC. MLPA analysis is a useful method for the genetic confirmation of TSC2/PKD1 CGDS.

• Journal of Veterinary Science
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• v.21 no.6
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• pp.88.1-88.13
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• 2020

Background: Listeria monocytogenes is a gram-positive bacterium that causes listeriosis mainly in immunocompromised hosts. It can also cause foodborne outbreaks and has the ability to adapt to various environments. Peptide uptake in gram-positive bacteria is enabled by oligopeptide permeases (Opp) in a process that depends on ATP hydrolysis by OppD and F. Previously a putative protein Lmo2193 was predicted to be OppD, but little is known about the role of OppD in major processes of L. monocytogenes, such as growth, virulence, and biofilm formation. Objectives: To determine whether the virulence traits of L. monocytogenes are related to OppD. Methods: In this study, Lmo2193 gene deletion and complementation strains of L. monocytogenes were generated and compared with a wild-type strain for the following: adhesiveness, invasion ability, intracellular survival, proliferation, 50% lethal dose (LD₅₀) to mice, and the amount bacteria in the mouse liver, spleen, and brain. Results: The results showed that virulence of the deletion strain was 1.34 and 0.5 orders of magnitude higher than that of the wild-type and complementation strains, respectively. The function of Lmo2193 was predicted and verified as OppD from the ATPase superfamily. Deletion of lmo2193 affected the normal growth of L. monocytogenes, reduced its virulence in cells and mice, and affected its ability to form biofilms. Conclusions: Deletion of the oligopeptide transporter Lmo2193 decreases the virulence of L. monocytogenes. These effects may be related to OppD's function, which provides a new perspective on the regulation of oligopeptide transporters in L. monocytogenes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5633-5636
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• 2012

Purpose: Breast cancer is an important cause of cancer-related death in women. Numerous studies have evaluated the association between the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene and breast cancer risk. However, the specific association is still controversial rather than conclusive. Therefore, we performed a meta-analysis of related studies to address this controversy. Methods: PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association between the I/D polymorphism in the ACE gene and susceptibility to breast cancer. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Results: 10 separate studies of 7 included articles with 10,888 subjects on the relation between the I/D polymorphism in the ACE gene and breast cancer were analyzed by meta-analysis, and our results showed no association between the I/D polymorphism in the ACE gene and breast cancer in total population and different populations. No publication bias was found in the present study. Conclusions: The ACE I/D polymorphism may not be associated with breast cancer risk. Further large and well-designed studies are needed to confirm this conclusion.