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cDNA cloning of fast skeletal myosin heavy chain of white croaker fish Pennahia argentata
s107 PlS-14
PlS-16
Variation in the beat shock responses of congeneric marine snails (genus Tegulu) from different thermal habitats
Energy balance of pregnant diabetic rate
Tomanek L and Somero GN Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950, USA We studied three temperate and one subtropical snail species of the genus Teguiu that differ in their distribution along the intertidal-to-subtidal transition. The temperate T. finebrah is limited to the intertidal zone and T. brunneu and T. montereyi are found in the subtidal zone. The subtropical T. rugosa is also limited to the intertidal zone. We hypothesized that, due to differing body temperatures and thermotolerance, species would vary adaptively in their expression of heat shock proteins (hsp’s). By measuring the incorporation of 35Smethionine and -cysteine into newly synthesized proteins we examined the effects of short-term heat stress and thermal acclimation on 90, 77, 70 and 38 kDa hsp’s. We compared the onset, maximal and upper temperature of hsp expression in the four species after acclimation to 13”, 18” and 23°C. These characteristics were lowest in the two temperate subtidal, intermediate in the temperate intertidal and highest in the subtropical intertidal species. The upper thermal limit of hsp synthesis correlated closely with thermotolerance limits. In T. brunnea and T. montereyi, synthesis ceased at temperatures below body temperatures that T. funebralis commonly experiences in the intertidal zone. Acclimation shifted onset temperature and the temperature of maximal expression for certain hsp’s, but not the upper thermal limits of hsp synthesis (and protein synthesis per se). Despite the occurrence of acclimatory plasticity, we found genetically-fixed differences that may set limits to thermotolerance and distribution ranges.
Yamada R, Griggio MA and LUZJ Departamento de Fisiologia, Universidade Paula, S&o Paulo, SP, Brazil.
Federal de SIo
Pregnancy changes several parameters of the energy balance. Diabetes affects the metabolism of the main nutrients on the animal organism. This study was undertaken to evaluate the effect of diabetes mellitus on the energy balance of pregnant and
non-pregnant rats. 4 groups of Wistar EPM-1 female rats were used: Non-pregnant control, pregnant control, non-pregnant diabetic, and pregnant diabetic. Diabetes was induced by intraperitonial injection of one dose of streptozotocin (60 mg/kg). After the first 48 hours following streptozotocin the animals received insulin subcutaneously (1 I.U. daily) so that the glicemia was kept at a minimum of 250 mg/dl. In the 15ti day after streptozotocin the rats were allowed to mating. In the 21” day of pregnancy the animals were killed and carcasses, feces, urine, placentae, and offspring were prepared for calorimetric analysis (Ika 400 C, Germany). The results showed that the diabetic animals presented a significantly higher energy expenditure but with similar energy intake as the controls, which led to a reduced energy gain of diabetic rats. Financial FAPESP,
Support: Brazil
Universidade
de Mogi
das
Cruzes
and
PlS-17 cDNA cloning of fast skeletal myosin heavy chain of white croaker fish Pennahia argentata
PM-15 The stress response is protective: cross protection in fish Todtiam AE, Teng ES and Iwama GK Faculty of Agricultural Sciences and the Canadian Bacterial Diseases Network, University of British Columbia, Vancouver, BC, Canada V6T 124. Animals respond to stressors at all levels of organization. The cellular stress response involves the production of heat shock proteins (hsp). There is evidence that the induction of hsp protects the cell against subsequent stressors. This study examined whether a mild heat shock would confer protection against a toxic stressor. A +lO “C heat shock increased the survival of triploid rainbow trout (Oncorhynchus mykiss) subsequently exposed to a lethal dose of a chemical toxicant, sodium dodecyl sulphate (SDS). However, in diploid fish, this preliminary heat shock increased mortality when the fish were subsequently exposed to the same lethal dose of SDS. The involvement of hsps in cross protection in fish requires further investigation. It is known that triploid rainbow trout are particularly susceptible to toxicant stress and therefore, it is possible that cross protection may be dependent on the fish’s specific sensitivities to the stressors.
Yoon S H, Hirayama Y, and Watabe S Laboratory of Aquatic Molecular Biology and Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan. In general, cold-water fish contains muscle proteins more unstable than those from warm-water fish. White croaker is one of the most diversified bottom fish species and distributes to regions as diverse as from temperate to tropical water. In this study, we isolated a cDNA clone which encodes the full-length of fast skeletal myosin heavy chain from the fish Pennahia argentatu inhabiting the sea around Japan to compare its structural properties with those of Alaska pollack Theragra chalcogramma, a typical cold-water bottom fish in Japan. A cDNA library was constructed from the dorsal fast skeletal muscle of P.argentata and screened for myosin heavy chain using the antibody raised against carp fast skeletal myosin. The full-length cDNA was further cloned by reverse transcriptionPCR and S-RACE using first-strand cDNA as a template together with appropriate sets of primers. The entire cDNA consisted of 5,790 nt with 5’- and 3’-untranslated regions of 64 and 129 bp, respectively, and encoded 1,930 amino acid residues. Hydrophilic@ analysis revealed that myosin subfragment- region contained a mixed profile of hydrophilic and hydrophobic residues, whereas the rod region was predominantly occupied by hydrophilic residues. Comparison of amino acid sequences for myosin heavy chains from white croaker and Alaska pollack’,‘) resulted in 88.0, 91.6, and 91.0% homology for myosin subfragment-1, subfragment2, and light meromyosin fragment regions, respectively. 1) Togashi et al. (1997) DDBJ/EMBUGenBank DNA databases under accession No. ABO00214. 2) Ojima et al. (1998) Fisheries Sci., 64, 812 - 819.
PlS-16
Variation in the beat shock responses of congeneric marine snails (genus Tegulu) from different thermal habitats
Energy balance of pregnant diabetic rate
Tomanek L and Somero GN Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950, USA We studied three temperate and one subtropical snail species of the genus Teguiu that differ in their distribution along the intertidal-to-subtidal transition. The temperate T. finebrah is limited to the intertidal zone and T. brunneu and T. montereyi are found in the subtidal zone. The subtropical T. rugosa is also limited to the intertidal zone. We hypothesized that, due to differing body temperatures and thermotolerance, species would vary adaptively in their expression of heat shock proteins (hsp’s). By measuring the incorporation of 35Smethionine and -cysteine into newly synthesized proteins we examined the effects of short-term heat stress and thermal acclimation on 90, 77, 70 and 38 kDa hsp’s. We compared the onset, maximal and upper temperature of hsp expression in the four species after acclimation to 13”, 18” and 23°C. These characteristics were lowest in the two temperate subtidal, intermediate in the temperate intertidal and highest in the subtropical intertidal species. The upper thermal limit of hsp synthesis correlated closely with thermotolerance limits. In T. brunnea and T. montereyi, synthesis ceased at temperatures below body temperatures that T. funebralis commonly experiences in the intertidal zone. Acclimation shifted onset temperature and the temperature of maximal expression for certain hsp’s, but not the upper thermal limits of hsp synthesis (and protein synthesis per se). Despite the occurrence of acclimatory plasticity, we found genetically-fixed differences that may set limits to thermotolerance and distribution ranges.
Yamada R, Griggio MA and LUZJ Departamento de Fisiologia, Universidade Paula, S&o Paulo, SP, Brazil.
Federal de SIo
Pregnancy changes several parameters of the energy balance. Diabetes affects the metabolism of the main nutrients on the animal organism. This study was undertaken to evaluate the effect of diabetes mellitus on the energy balance of pregnant and
non-pregnant rats. 4 groups of Wistar EPM-1 female rats were used: Non-pregnant control, pregnant control, non-pregnant diabetic, and pregnant diabetic. Diabetes was induced by intraperitonial injection of one dose of streptozotocin (60 mg/kg). After the first 48 hours following streptozotocin the animals received insulin subcutaneously (1 I.U. daily) so that the glicemia was kept at a minimum of 250 mg/dl. In the 15ti day after streptozotocin the rats were allowed to mating. In the 21” day of pregnancy the animals were killed and carcasses, feces, urine, placentae, and offspring were prepared for calorimetric analysis (Ika 400 C, Germany). The results showed that the diabetic animals presented a significantly higher energy expenditure but with similar energy intake as the controls, which led to a reduced energy gain of diabetic rats. Financial FAPESP,
Support: Brazil
Universidade
de Mogi
das
Cruzes
and
PlS-17 cDNA cloning of fast skeletal myosin heavy chain of white croaker fish Pennahia argentata
PM-15 The stress response is protective: cross protection in fish Todtiam AE, Teng ES and Iwama GK Faculty of Agricultural Sciences and the Canadian Bacterial Diseases Network, University of British Columbia, Vancouver, BC, Canada V6T 124. Animals respond to stressors at all levels of organization. The cellular stress response involves the production of heat shock proteins (hsp). There is evidence that the induction of hsp protects the cell against subsequent stressors. This study examined whether a mild heat shock would confer protection against a toxic stressor. A +lO “C heat shock increased the survival of triploid rainbow trout (Oncorhynchus mykiss) subsequently exposed to a lethal dose of a chemical toxicant, sodium dodecyl sulphate (SDS). However, in diploid fish, this preliminary heat shock increased mortality when the fish were subsequently exposed to the same lethal dose of SDS. The involvement of hsps in cross protection in fish requires further investigation. It is known that triploid rainbow trout are particularly susceptible to toxicant stress and therefore, it is possible that cross protection may be dependent on the fish’s specific sensitivities to the stressors.
Yoon S H, Hirayama Y, and Watabe S Laboratory of Aquatic Molecular Biology and Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan. In general, cold-water fish contains muscle proteins more unstable than those from warm-water fish. White croaker is one of the most diversified bottom fish species and distributes to regions as diverse as from temperate to tropical water. In this study, we isolated a cDNA clone which encodes the full-length of fast skeletal myosin heavy chain from the fish Pennahia argentatu inhabiting the sea around Japan to compare its structural properties with those of Alaska pollack Theragra chalcogramma, a typical cold-water bottom fish in Japan. A cDNA library was constructed from the dorsal fast skeletal muscle of P.argentata and screened for myosin heavy chain using the antibody raised against carp fast skeletal myosin. The full-length cDNA was further cloned by reverse transcriptionPCR and S-RACE using first-strand cDNA as a template together with appropriate sets of primers. The entire cDNA consisted of 5,790 nt with 5’- and 3’-untranslated regions of 64 and 129 bp, respectively, and encoded 1,930 amino acid residues. Hydrophilic@ analysis revealed that myosin subfragment- region contained a mixed profile of hydrophilic and hydrophobic residues, whereas the rod region was predominantly occupied by hydrophilic residues. Comparison of amino acid sequences for myosin heavy chains from white croaker and Alaska pollack’,‘) resulted in 88.0, 91.6, and 91.0% homology for myosin subfragment-1, subfragment2, and light meromyosin fragment regions, respectively. 1) Togashi et al. (1997) DDBJ/EMBUGenBank DNA databases under accession No. ABO00214. 2) Ojima et al. (1998) Fisheries Sci., 64, 812 - 819.