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1.
Braz. j. biol ; 82: 1-24, 2022.
Article in English | LILACS, VETINDEX | ID: biblio-1468567

ABSTRACT

The mutations are genetic changes in the genome sequences and have a significant role in biotechnology, genetics, and molecular biology even to find out the genome sequences of a cell DNA along with the viral RNA sequencing. The mutations are the alterations in DNA that may be natural or spontaneous and induced due to biochemical reactions or radiations which damage cell DNA. There is another cause of mutations which is known as transposons or jumping genes which can change their position in the genome during meiosis or DNA replication. The transposable elements can induce by self in the genome due to cellular and molecular mechanisms including hypermutation which caused the localization of transposable elements to move within the genome. The use of induced mutations for studying the mutagenesis in crop plants is very common as well as a promising method for screening crop plants with new and enhanced traits for the improvement of yield and production. The utilization of insertional mutations through transposons or jumping genes usually generates stable mutant alleles which are mostly tagged for the presence or absence of jumping genes or transposable elements. The transposable elements may be used for the identification of mutated genes in crop plants and even for the stable insertion of transposable elements in mutated crop plants. The guanine nucleotide-binding (GTP) proteins have an important role in inducing tolerance in rice plants to combat abiotic stress conditions.


Mutações são alterações genéticas nas sequências do genoma e têm papel significativo na biotecnologia, genética e biologia molecular, até mesmo para descobrir as sequências do genoma de um DNA celular junto com o sequenciamento do RNA viral. As mutações são alterações no DNA que podem ser naturais ou espontâneas e induzidas devido a reações bioquímicas ou radiações que danificam o DNA celular. Há outra causa de mutações, conhecida como transposons ou genes saltadores, que podem mudar sua posição no genoma durante a meiose ou a replicação do DNA. Os elementos transponíveis podem induzir por si próprios no genoma devido a mecanismos celulares e moleculares, incluindo hipermutação que causou a localização dos elementos transponíveis para se moverem dentro do genoma. O uso de mutações induzidas para estudar a mutagênese em plantas cultivadas é muito comum, bem como um método promissor para a triagem de plantas cultivadas com características novas e aprimoradas para a melhoria da produtividade e da produção. A utilização de mutações de inserção por meio de transposons ou genes saltadores geralmente gera alelos mutantes estáveis que são marcados quanto à presença ou ausência de genes saltadores ou elementos transponíveis. Os elementos transponíveis podem ser usados para a identificação de genes mutados em plantas de cultivo e até mesmo para a inserção estável de elementos transponíveis em plantas de cultivo mutadas. As proteínas de ligação ao nucleotídeo guanina (GTP) têm papel importante na indução de tolerância em plantas de arroz para combater as condições de estresse abiótico.


Subject(s)
DNA Transposable Elements/genetics , Mutation/genetics , Guanine Nucleotides/analysis , Oryza/genetics
2.
J. appl. oral sci ; 26: e20170451, 2018. graf
Article in English | LILACS, BBO | ID: biblio-893699

ABSTRACT

Abstract Local administration of toll-like receptor 9 (TLR9), agonist cytidine-phosphate-guanosine oligodeoxynucleotide (CpG ODNs), and CD40 ligand (CD40L) can decrease ligature-induced periodontal inflammation and bone loss in wild type (WT) mouse. Objective: This study aimed to explore whether such effect is dependent on TLR9 signaling. Material and Methods: Purified spleen B cells isolated from WT C57BL/6J mice and TLR9 knockout (KO) mice were cultured for 48 hours under the following conditions: CD40L, CpG+CD40L, CpG at low, medium and high doses. We determined B cell numbers using a hemocytometer at 24 h and 48 h. Percentages of CD1dhiCD5+ B cells were detected by flow cytometry. Interleukin-10 (IL-10) mRNA expression and protein secretion were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and by ELISA, respectively. The silk ligature was tied around the maxillary second molars for 14 days, during which the CpG+CD40L mixture or PBS was injected into palatal gingiva on days 3, 6, and 9. Results: For both WT and TLR9 KO mice, CpG significantly induced B cell proliferation, increased IL-10 mRNA expression and protein secretion of IL-10 but reduced CD1dhiCD5+ B cells population; local injection of CpG+CD40L mixture significantly decreased alveolar bone loss and the number of TRAP-positive cells adjacent to the alveolar bone surface, and significantly increased the gingival mRNA expression of IL-10 and decreased RANKL and IFN-γ mRNA expression. Conclusions: These results indicated that CpG plus CD40L decreased periodontal inflammation and alveolar bone loss in a TLR9-independent manner in ligature-induced experimental periodontitis.


Subject(s)
Animals , Oligodeoxyribonucleotides/pharmacology , Periodontitis/drug therapy , Alveolar Bone Loss/drug therapy , CD40 Ligand/pharmacology , Cytidine/pharmacology , Toll-Like Receptor 9/drug effects , Guanine Nucleotides/pharmacology , Reference Values , Time Factors , Enzyme-Linked Immunosorbent Assay , B-Lymphocytes/drug effects , Cells, Cultured , Adjuvants, Immunologic/pharmacology , Reproducibility of Results , Interleukin-10/analysis , Disease Models, Animal , Toll-Like Receptor 9/analysis , Real-Time Polymerase Chain Reaction , Flow Cytometry , Gingiva/drug effects , Gingiva/pathology , Mice, Inbred C57BL
3.
Yonsei Medical Journal ; : 1289-1296, 2014.
Article in English | WPRIM | ID: wpr-210331

ABSTRACT

PURPOSE: This study aimed to assess the role of thiopurine S-methyltransferase (TPMT) and 6-thioguanine nucleotide (6-TGN) as predictors of clinical response and side effects to azathioprine (AZA), and estimate the optimal AZA dose in Korean pediatric inflammatory bowel disease (IBD) patients. MATERIALS AND METHODS: One hundred and nine pediatric IBD patients in whom AZA treatment was required were enrolled. Thiopurine metabolites were monitored since September 2010. Among them, 83 patients who had prescribed AZA for at least 3 months prior to September 2010 were enrolled and followed until October 2011 to evaluate optimal AZA dose, adverse effects and disease activity before and after thiopurine metabolite monitoring. RESULTS: The result of the TPMT genotype was that 102 patients were *1/*1 (wild type), four were *1/*3C, one was *1/*6, one was *1/*16 (heterozygote) and one was *3C/*3C (homozygote). Adverse effects happened in 31 patients pre-metabolite monitoring and in only nine patients post-metabolite monitoring. AZA dose was 1.4+/-0.31 mg/kg/day before monitoring and 1.1+/-0.46 mg/kg/day after monitoring (p<0.001). However, there were no statistical differences in disease activity during metabolite monitoring period (p=0.34). Adverse effects noticeably decreased although reduction of the AZA dose since monitoring. CONCLUSION: TPMT genotype and thiopurine metabolite monitoring could be helpful to examine TPMT genotypes before administering AZA and to measure 6-TGN concentrations during prescribing AZA in IBD patients.


Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Azathioprine/adverse effects , Genotype , Guanine Nucleotides/metabolism , Inflammatory Bowel Diseases/drug therapy , Methyltransferases/genetics , Republic of Korea , Risk Factors , Thionucleotides/metabolism , Treatment Outcome
4.
Korean Journal of Dermatology ; : 1644-1649, 2003.
Article in Korean | WPRIM | ID: wpr-203956

ABSTRACT

Mycophenolate mofetil(MMF) is a new immunosuppressant which non-competitively and reversibly blocks the de novo synthesis of guanine nucleotides required for DNA and RNA synthesis during lymphocyte proliferation. So MMF selectively inhibits lymphocyte proliferation and it has less side-effects than other immunosuppressants. We described 2 cases of generalized pustular psoriasis improved with MMF. We administered MMF combined with cyclosporin in case 1 and acitretin in case 2. Both patients markedly improved with MMF administration 3 days after and had no severe side-effects. Thus the authors thought that MMF appears to be an effective therapeutic alternative in the treatment of generalized pustular psoriasis.


Subject(s)
Humans , Acitretin , Cyclosporine , DNA , Guanine Nucleotides , Immunosuppressive Agents , Lymphocytes , Psoriasis , RNA
5.
Experimental & Molecular Medicine ; : 30-35, 1999.
Article in English | WPRIM | ID: wpr-56321

ABSTRACT

C-Terminal carboxyl methylation of a human placental 23 kDa protein catalyzed by membrane-associated methyltransferase has been investigated. The 23 kDa protein substrate methylated was partially purified by DEAE-Sephacel, hydroxyapatite and Sephadex G-100 gel filtration chromatographies. The substrate protein was eluted on Sephadex G-100 gel filtration chromatography as a protein of about 29 kDa. In the absence of Mg2+, the methylation was stimulated by guanine nucleotides (GTP, GDP and GTPgammaS), but in the presence of Mg2+, only GTPgammaS stimulated the methylation which was similar to the effect on the G25K/rhoGDI complex. AFC, an inhibitor of C-terminal carboxyl methylation, inhibited the methylation of human placental 23 kDa protein. These results suggests that the substrate is a small G protein different from the G25K and is methylated on C-terminal isoprenylated cysteine residue. This was also confirmed by vapor phase analysis. The methylated substrate protein was redistributed to membrane after in vitro methylation, suggesting that the methylation of this protein is important for the redistribution of the 23 kDa small G protein for its putative role in intracellular signaling.


Subject(s)
Female , Humans , Pregnancy , Cysteine/metabolism , GTP-Binding Proteins/metabolism , Guanine Nucleotides/pharmacology , Methylation , Placenta/metabolism , Placenta/enzymology , Pregnancy Proteins/metabolism , Protein Methyltransferases/metabolism
6.
Rev. Inst. Med. Trop. Säo Paulo ; 40(4): 237-40, July-Aug. 1998. ilus
Article in English | LILACS | ID: lil-225882

ABSTRACT

Neste trabalho, nos investigamos o efeito da 8-Bromoguanosina, um composto imunoestimulador, na citotoxicidade de macrofagos infectados com Leishmania amazonensis em um sistema in vitro. Os resultados mostraram que macrofagos tratados com 8-Bromoguanosina pre- ou pos-infeccao foram capazes de reduzir a carga parasitaria, monitorada pelo numero de amastigotas por macrofago e a percentagem de celulas infectadas (i.e. indice fagocitico). Sendo a 8-Bromoguanosina inocua para promastigotas, concluimos que o composto induz ativacao celular. Os macrofagos produziriam interferon alfa e beta e teriam seus mecanismos leishmanicidas estimulados. Esses resultados sugerem que compostos como a 8-Bromoguanosina (ribonucleosideos de guanina) podem auxiliar no tratamento contra patogenos intracelulares


Subject(s)
Animals , Mice , Killer Cells, Natural , Guanine Nucleotides/toxicity , In Vitro Techniques , Leishmania/immunology , Adjuvants, Immunologic/toxicity , Cell Culture Techniques , Parasitic Diseases/therapy , Interferon-alpha/pharmacology , Interferon-beta/pharmacology , Leishmania/classification
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