As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to ...As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to environmental stimuli. CaM was found to be extracellular both in guard cells of broad bean leaves and in epidermal cells by immuno-electron microscopy and immuno-fluorescence microscopy techniques. Exogenous purified CaM enhanced stomatal closure and inhibited stomatal opening with an optimal concentration of 10(-8) mol/L; CaM antagonist W7-agarose and anti-CaM serum, which were membrane-impermeable macromolecules, inhibited stomatal closure and promoted stomatal opening. All these data showed that endogenous extracellular CaM. of guard cells did promote stomatal closure and inhibit stomatal opening, and could he active only outside the cells. Therefore under natural conditions, the endogenous extracellular CaM of guard cells might regulate stomatal movements as a primary messenger together with other signal molecules, and might be an important linkage between environmental stimuli and cell responses.展开更多
Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility ...Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility and broodstock performance. Snakeskin gourami broodfish were fed with isocaloric diets （DE 3,000 a： 50 Kcal/kg） contained 32% crude protein. The levels of substitution were 0%, 50%, 75% and 100% of protein from fish meal （equal to 0%, 14.57%, 21.75% and 29.03% silk worm by weight）. The study was assigned in CRD with 4 treatments and 3 replications. Six hundred of snakeskin gourami with five-month old and average weight of 78.67 ± 2.15 g in female and average weight of 73.00 ± 2.49 g in male were stocked in 12 cages. Fifty fishes of 25 females and 25 males were reared in each cage and fed experimental diet for five months. The result indicated that protein digestibility of test diets were significantly decrease （P 〈 0.05） according to the level of silkworm pupae in diets where as the dry matter digestibility showed no significantly different （P 〉 0.05）. The growth performance and egg fecundity were significantly decreased （P 〈 0.05） according to the levels of silkworm pupae. In contrast, egg quality in term of fry number on first spawned, fingering number on first spawned were not significantly different （P 〉 0.05）. The survival rate of one month nursing fish on first spawned were significantly different （P 〈 0.05）. Hence, silkworm pupae could substitution for 50% of protein from fish meal （14.57% by weight） in snakeskin gourami broodstock diets without any adverse effect on egg quality.展开更多
Effects of ecdysteroid and juvenile hormone (JH) on vitellogenesis of the Japanese oak silkworm, Antheraea yamamai are reported in this article. After topical treatment with 20 hydroxyecdysone alone or JH analog ...Effects of ecdysteroid and juvenile hormone (JH) on vitellogenesis of the Japanese oak silkworm, Antheraea yamamai are reported in this article. After topical treatment with 20 hydroxyecdysone alone or JH analog (i.e. methoprene) alone and combined treatment with these two chemicals, vitellogenin (Vg) titers in the fat body and haemolymph at the pupal stage were mostly higher than those of the control, indicating that both ecdysteroid and JH exerted a promoting effect on the synthesis of Vg. In contrast, the Vg uptake was markedly inhibited by JH while stimulating effect of the ecdysteroid could be shown that vitellin (Vt) titer in the ovary was lower after methoprene treatments, but higher after 20 hydroxyecdyson treatments. Meanwhile, effects of these two hormones on Vg synthesis in the fat body were also tested with the incubation in vitro with Grace medium containing 3H leucine and the hormones. The results demonstrated that Vg synthesis was stimulated after treating with methoprene alone or 20 hydroxyecdysone alone and combined treating with these two chemicals, and particularly ecdysteroid had more marked positive effect. To comprehensively concluded our results, it could be regarded that ecdysteroid play the main role in the regulation of vitellogenesis for the Japanese oak silkworm.展开更多
Developmental changes in hemolymph ecdysteroid level, ecdysteroid synthesis by prothoracic glands （PGs） in vitro, prothoracicotropic hormone （PTTH） activity in brain extracts, and PTTH activity in the hemolymph we...Developmental changes in hemolymph ecdysteroid level, ecdysteroid synthesis by prothoracic glands （PGs） in vitro, prothoracicotropic hormone （PTTH） activity in brain extracts, and PTTH activity in the hemolymph were measured during the fifth larval instar of the Eri silkworm, Samia cynthia ricini. The changing patterns of hemolymph ecdysteroid level and ecdysteroid synthesis by laGs in vitro are similar to each other, with maximums on day 9. However, on this day, hemolymph ecdysteroid level was substantially higher than ecdysteroid synthesis by PGs in vitro suggesting a high PTTH activity in the hemolymph on day 9. Moreover, the changing pattern of PTTH activity in brain extracts is also similar to that of PTTH activity in the hemolymph, both peaking on day 9. However, on this day, activity in brain extracts was much smaller than PTTH activity in the hemolymph implying that most PTTH synthesized by the brain is secreted to the hemolymph and the brain stores a very little amount of PTTH. This study provides unique insights onto the hormonal regulation of ecdysteroid synthesis in the Eri silkworm and is useful for our future studies on signal transduction of insect neurolaelatides.展开更多
文摘As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to environmental stimuli. CaM was found to be extracellular both in guard cells of broad bean leaves and in epidermal cells by immuno-electron microscopy and immuno-fluorescence microscopy techniques. Exogenous purified CaM enhanced stomatal closure and inhibited stomatal opening with an optimal concentration of 10(-8) mol/L; CaM antagonist W7-agarose and anti-CaM serum, which were membrane-impermeable macromolecules, inhibited stomatal closure and promoted stomatal opening. All these data showed that endogenous extracellular CaM. of guard cells did promote stomatal closure and inhibit stomatal opening, and could he active only outside the cells. Therefore under natural conditions, the endogenous extracellular CaM of guard cells might regulate stomatal movements as a primary messenger together with other signal molecules, and might be an important linkage between environmental stimuli and cell responses.
文摘Substitution of silkworm pupae （Bombyx mori） for fish meal in broodstock diets for snakeskin gourami （Trichogaster pectoralis） was conducted in order to evaluate the effect of silkworm pupae on feed digestibility and broodstock performance. Snakeskin gourami broodfish were fed with isocaloric diets （DE 3,000 a： 50 Kcal/kg） contained 32% crude protein. The levels of substitution were 0%, 50%, 75% and 100% of protein from fish meal （equal to 0%, 14.57%, 21.75% and 29.03% silk worm by weight）. The study was assigned in CRD with 4 treatments and 3 replications. Six hundred of snakeskin gourami with five-month old and average weight of 78.67 ± 2.15 g in female and average weight of 73.00 ± 2.49 g in male were stocked in 12 cages. Fifty fishes of 25 females and 25 males were reared in each cage and fed experimental diet for five months. The result indicated that protein digestibility of test diets were significantly decrease （P 〈 0.05） according to the level of silkworm pupae in diets where as the dry matter digestibility showed no significantly different （P 〉 0.05）. The growth performance and egg fecundity were significantly decreased （P 〈 0.05） according to the levels of silkworm pupae. In contrast, egg quality in term of fry number on first spawned, fingering number on first spawned were not significantly different （P 〉 0.05）. The survival rate of one month nursing fish on first spawned were significantly different （P 〈 0.05）. Hence, silkworm pupae could substitution for 50% of protein from fish meal （14.57% by weight） in snakeskin gourami broodstock diets without any adverse effect on egg quality.
文摘Effects of ecdysteroid and juvenile hormone (JH) on vitellogenesis of the Japanese oak silkworm, Antheraea yamamai are reported in this article. After topical treatment with 20 hydroxyecdysone alone or JH analog (i.e. methoprene) alone and combined treatment with these two chemicals, vitellogenin (Vg) titers in the fat body and haemolymph at the pupal stage were mostly higher than those of the control, indicating that both ecdysteroid and JH exerted a promoting effect on the synthesis of Vg. In contrast, the Vg uptake was markedly inhibited by JH while stimulating effect of the ecdysteroid could be shown that vitellin (Vt) titer in the ovary was lower after methoprene treatments, but higher after 20 hydroxyecdyson treatments. Meanwhile, effects of these two hormones on Vg synthesis in the fat body were also tested with the incubation in vitro with Grace medium containing 3H leucine and the hormones. The results demonstrated that Vg synthesis was stimulated after treating with methoprene alone or 20 hydroxyecdysone alone and combined treating with these two chemicals, and particularly ecdysteroid had more marked positive effect. To comprehensively concluded our results, it could be regarded that ecdysteroid play the main role in the regulation of vitellogenesis for the Japanese oak silkworm.
文摘Developmental changes in hemolymph ecdysteroid level, ecdysteroid synthesis by prothoracic glands （PGs） in vitro, prothoracicotropic hormone （PTTH） activity in brain extracts, and PTTH activity in the hemolymph were measured during the fifth larval instar of the Eri silkworm, Samia cynthia ricini. The changing patterns of hemolymph ecdysteroid level and ecdysteroid synthesis by laGs in vitro are similar to each other, with maximums on day 9. However, on this day, hemolymph ecdysteroid level was substantially higher than ecdysteroid synthesis by PGs in vitro suggesting a high PTTH activity in the hemolymph on day 9. Moreover, the changing pattern of PTTH activity in brain extracts is also similar to that of PTTH activity in the hemolymph, both peaking on day 9. However, on this day, activity in brain extracts was much smaller than PTTH activity in the hemolymph implying that most PTTH synthesized by the brain is secreted to the hemolymph and the brain stores a very little amount of PTTH. This study provides unique insights onto the hormonal regulation of ecdysteroid synthesis in the Eri silkworm and is useful for our future studies on signal transduction of insect neurolaelatides.
