Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes
Electrophoretic thermostability tests of soluble malate dehydrogenases (sMDH) isozymes in tissue extracts of 21 subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes showed three distinct results. The first, characterized by thermal stability of the slowest-migrating b...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Sociedade Brasileira de Genética
1998-06-01
|
| Series: | Genetics and Molecular Biology |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200004 |
| _version_ | 1818585640035418112 |
|---|---|
| author | Maria do Carmo Monteiro Maria Luiza B. Schwantes Arno Rudi Schwantes Maria Regina de Aquino Silva |
| author_facet | Maria do Carmo Monteiro Maria Luiza B. Schwantes Arno Rudi Schwantes Maria Regina de Aquino Silva |
| author_sort | Maria do Carmo Monteiro |
| collection | DOAJ |
| description | Electrophoretic thermostability tests of soluble malate dehydrogenases (sMDH) isozymes in tissue extracts of 21 subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes showed three distinct results. The first, characterized by thermal stability of the slowest-migrating band or A-isoform, was detected in 52% of all species. The second, exhibited in 29% of the species analyzed, had a bidirectionally divergent pattern of their sMDH locus expression, and was characterized by a nondivergent thermostability pattern of both sMDH-A* and B*. In the third category, obtained in 19% of the species studied (the four Siluriformes species), thermostability of the fastest-migrating bands, or B-isoforms, was observed. Comparison of the effects of habitat temperature on the activity of paralogous and orthologous isoforms in tissue extracts of two of these species with different thermostability properties (Leporinus friderici - thermostable sMDH-A*, and Pimelodus maculatus - reverse thermostability properties or reverse electrophoretic pattern), collected during winter and summer months, showed that A and B subunits were present at different quantitative levels and their activities were nearly season independent. Differences in susceptibility to temperature (50°C) of both sMDH loci from tissue extracts of these species were found. In P. maculatus, these susceptibilities helped strengthen one of the hypotheses: the reverse thermostability pattern, where the fastest-migrating band or the B-isoform was the thermostable sMDH. Thus, temperature differences among orthologous homologues of sMDH seem to have occurred in these acclimatized species, where the fastest-migrating band, usually muscle specific and thermolabile in most teleosts, appeared in P. maculatus as the thermostable isoform.<br>No presente trabalho, mostramos em ortólogos da sMDH de 21 espécies de peixes subtropicais das ordens Characiformes, Siluriformes e Perciformes, três diferentes estabilidades térmicas. A primeira, caracterizada pela termoestabilidade do componente menos anódico ou isoforma-A, foi detectada em 52% de todas as espécies. A segunda, exibida por 29% das espécies aqui analisadas, caracterizou-se por um padrão não-divergente de termoestabilidade dos locos sMDH-A* e sMDH-B*. Na terceira resposta, obtida em 19% das espécies analisadas (as 4 espécies Siluriformes), foi observada a termoestabilidade da banda mais anódica ou isoforma-B. O efeito da temperatura ambiental na atividade relativa de isoformas parálogas e ortólogas de duas dessas espécies com diferentes respostas térmicas (Leporinus friderici - sMDH-A*, termoestável, e Pimelodus maculatus, termoestabilidade reversa ou padrão eletroforético reverso), coletadas em meses de inverno e de verão, mostrou que as subunidades A e B estão presentes em seus extratos de tecidos em diferentes níveis quantitativos e suas atividades relativas são, praticamente, independentes da época de coleta. Na incubação de extratos de tecidos dessas 2 espécies a 50°C, diferentes respostas de inativação térmica foram dadas pelos locos da sMDH. Em P. maculatus, a resposta obtida em músculo esquelético ajudou a escolher a hipótese mais provável - a da termoestabilidade reversa, onde a banda mais anódica ou isoforma-B é a sMDH termoestável. Assim, diferenças na susceptibilidade à temperatura parecem ter ocorrido entre homólogos ortólogos da sMDH, nessas espécies, onde a banda mais rápida, normalmente músculo-específica e termolábil na maioria dos teleósteos, aparece em P. maculatus como a isoforma termoestável. |
| first_indexed | 2024-12-16T08:40:17Z |
| format | Article |
| id | doaj.art-cd662f6ccf894a8f99498913a843e119 |
| institution | Directory Open Access Journal |
| issn | 1415-4757 1678-4685 |
| language | English |
| last_indexed | 2024-12-16T08:40:17Z |
| publishDate | 1998-06-01 |
| publisher | Sociedade Brasileira de Genética |
| record_format | Article |
| series | Genetics and Molecular Biology |
| spelling | doaj.art-cd662f6ccf894a8f99498913a843e1192022-12-21T22:37:42ZengSociedade Brasileira de GenéticaGenetics and Molecular Biology1415-47571678-46851998-06-0121219110.1590/S1415-47571998000200004Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and PerciformesMaria do Carmo MonteiroMaria Luiza B. SchwantesArno Rudi SchwantesMaria Regina de Aquino SilvaElectrophoretic thermostability tests of soluble malate dehydrogenases (sMDH) isozymes in tissue extracts of 21 subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes showed three distinct results. The first, characterized by thermal stability of the slowest-migrating band or A-isoform, was detected in 52% of all species. The second, exhibited in 29% of the species analyzed, had a bidirectionally divergent pattern of their sMDH locus expression, and was characterized by a nondivergent thermostability pattern of both sMDH-A* and B*. In the third category, obtained in 19% of the species studied (the four Siluriformes species), thermostability of the fastest-migrating bands, or B-isoforms, was observed. Comparison of the effects of habitat temperature on the activity of paralogous and orthologous isoforms in tissue extracts of two of these species with different thermostability properties (Leporinus friderici - thermostable sMDH-A*, and Pimelodus maculatus - reverse thermostability properties or reverse electrophoretic pattern), collected during winter and summer months, showed that A and B subunits were present at different quantitative levels and their activities were nearly season independent. Differences in susceptibility to temperature (50°C) of both sMDH loci from tissue extracts of these species were found. In P. maculatus, these susceptibilities helped strengthen one of the hypotheses: the reverse thermostability pattern, where the fastest-migrating band or the B-isoform was the thermostable sMDH. Thus, temperature differences among orthologous homologues of sMDH seem to have occurred in these acclimatized species, where the fastest-migrating band, usually muscle specific and thermolabile in most teleosts, appeared in P. maculatus as the thermostable isoform.<br>No presente trabalho, mostramos em ortólogos da sMDH de 21 espécies de peixes subtropicais das ordens Characiformes, Siluriformes e Perciformes, três diferentes estabilidades térmicas. A primeira, caracterizada pela termoestabilidade do componente menos anódico ou isoforma-A, foi detectada em 52% de todas as espécies. A segunda, exibida por 29% das espécies aqui analisadas, caracterizou-se por um padrão não-divergente de termoestabilidade dos locos sMDH-A* e sMDH-B*. Na terceira resposta, obtida em 19% das espécies analisadas (as 4 espécies Siluriformes), foi observada a termoestabilidade da banda mais anódica ou isoforma-B. O efeito da temperatura ambiental na atividade relativa de isoformas parálogas e ortólogas de duas dessas espécies com diferentes respostas térmicas (Leporinus friderici - sMDH-A*, termoestável, e Pimelodus maculatus, termoestabilidade reversa ou padrão eletroforético reverso), coletadas em meses de inverno e de verão, mostrou que as subunidades A e B estão presentes em seus extratos de tecidos em diferentes níveis quantitativos e suas atividades relativas são, praticamente, independentes da época de coleta. Na incubação de extratos de tecidos dessas 2 espécies a 50°C, diferentes respostas de inativação térmica foram dadas pelos locos da sMDH. Em P. maculatus, a resposta obtida em músculo esquelético ajudou a escolher a hipótese mais provável - a da termoestabilidade reversa, onde a banda mais anódica ou isoforma-B é a sMDH termoestável. Assim, diferenças na susceptibilidade à temperatura parecem ter ocorrido entre homólogos ortólogos da sMDH, nessas espécies, onde a banda mais rápida, normalmente músculo-específica e termolábil na maioria dos teleósteos, aparece em P. maculatus como a isoforma termoestável.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200004 |
| spellingShingle | Maria do Carmo Monteiro Maria Luiza B. Schwantes Arno Rudi Schwantes Maria Regina de Aquino Silva Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes Genetics and Molecular Biology |
| title | Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes |
| title_full | Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes |
| title_fullStr | Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes |
| title_full_unstemmed | Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes |
| title_short | Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes |
| title_sort | thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders characiformes siluriformes and perciformes |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200004 |
| work_keys_str_mv | AT mariadocarmomonteiro thermalstabilityofsolublemalatedehydrogenaseisozymesofsubtropicalfishbelongingtotheorderscharaciformessiluriformesandperciformes AT marialuizabschwantes thermalstabilityofsolublemalatedehydrogenaseisozymesofsubtropicalfishbelongingtotheorderscharaciformessiluriformesandperciformes AT arnorudischwantes thermalstabilityofsolublemalatedehydrogenaseisozymesofsubtropicalfishbelongingtotheorderscharaciformessiluriformesandperciformes AT mariareginadeaquinosilva thermalstabilityofsolublemalatedehydrogenaseisozymesofsubtropicalfishbelongingtotheorderscharaciformessiluriformesandperciformes |