The present study shows that double-stranded RNA-dependent protein kinase （PKR） regulates the protein expres- sion level and phosphorylation of Bcl-2 and plays an anti-apoptotic role in human hepatocellular carcinom...The present study shows that double-stranded RNA-dependent protein kinase （PKR） regulates the protein expres- sion level and phosphorylation of Bcl-2 and plays an anti-apoptotic role in human hepatocellular carcinoma ceils （HepG2）. In various types of cells, saturated free fatty acids （FFAs）, such as palmitate, have been shown to induce cellular apoptosis by several mechanisms. Palmitate down-regulates the activity of PKR and thereby decreases the level of Bcl-2 protein, mediated in part by reduced activation of the NF-KB transcription factor. In addition to the level of Bel-2 protein, the phosphorylation of Bcl-2 at different amino acid residues, such as Ser70 and Ser87, is also important in regulating cellular apoptosis. The decrease in the phosphorylatiou of Bcl-2 at Ser70 upon exposure to palmitate is mediated by inhibition of PKR and possibly by c-Jun N-terminal kinase （JNK）, whereas the phosphory- lation of Bcl-2 at Ser87 is unaffected by palmitate or PKR. In summary, PKR mediates the regulation of the protein level and the phosphorylation status of Bel-2, providing a novel mechanism of palmitate-induced apoptosis in HepG2 cells.展开更多
Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both sal...Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both salts whereas uptake of Ca^2＋ retarded mainly by Na2SO4. Chlorophyll content was affected mainly by NaCl, while Na2SO4 treatment lowered the rate of photosynthetic activity. Both salt compounds caused accumulation of free amino acids including free proline but reduced the protein content in the leaves. The salt tolerance capacity of the broad beans plant in which the observations of the effect of salinity determined by different concentrations of NaCI and Na2SO4 on growth, chloroplast pigments, photosynthetic, free amino acids, free proline, protein and inorganic elements on plants are combined with observations on growth and yield, in order to arrive at a better understanding of their salt tolerance, has been studied and discussed in this paper. The results for the latter only （fruiting stage） are presented.展开更多
[Objective] This study was conducted to investigate the effects of light quality on growth and quality of Chinese kale(Brassica alboglabra Bailey). [Method]Chinese kale was grown in hydroponic under three different Li...[Objective] This study was conducted to investigate the effects of light quality on growth and quality of Chinese kale(Brassica alboglabra Bailey). [Method]Chinese kale was grown in hydroponic under three different Light Emitting Diode(LEDs) conditions [red∶blue=8∶1(8R1B), red∶blue=6∶3(6R3B) and red∶green∶blue=6∶2∶1(6R2G1B), 12 h light, 50 μmol/(m2·s)]. Then its growth and quality indices including root and shoot fresh weight and dry weight, concentrations of soluble protein, vitamin C, nitrate, soluble phenols, flavonoids, soluble sugar, free amino acids, and activity of nitrate reductase were measured. [Result] There was no significant difference in plant height, diameter of flower stalk and leaf number among three LED treatments. The fresh weight of shoot, root and plant in 8R1 B and 6R2G1 B was significantly higher than in 6R3 B. The dry weight of shoot and plant in 8R1 B was significantly higher than in 6R3 B. The concentrations of vitamin C, soluble protein and soluble sugar in flower stalk of 6R3 B treatment were significantly higher than those in 8R1 B and 6R2G1 B, while there was no remarkable difference in concentrations of reducing sugar, soluble phenol, flavonoids and free amino acid among the three treatments. The nitrate concentration in flower stalk of 6R3 B was significantly lower than in the other two treatments, and the activity of nitrate reductase in6R3 B was significantly higher than in the other two treatments. [Conclusion] The LED treatment of red:blue=6:3 was more suitable for the growth of Chinese kale.展开更多
文摘The present study shows that double-stranded RNA-dependent protein kinase （PKR） regulates the protein expres- sion level and phosphorylation of Bcl-2 and plays an anti-apoptotic role in human hepatocellular carcinoma ceils （HepG2）. In various types of cells, saturated free fatty acids （FFAs）, such as palmitate, have been shown to induce cellular apoptosis by several mechanisms. Palmitate down-regulates the activity of PKR and thereby decreases the level of Bcl-2 protein, mediated in part by reduced activation of the NF-KB transcription factor. In addition to the level of Bel-2 protein, the phosphorylation of Bcl-2 at different amino acid residues, such as Ser70 and Ser87, is also important in regulating cellular apoptosis. The decrease in the phosphorylatiou of Bcl-2 at Ser70 upon exposure to palmitate is mediated by inhibition of PKR and possibly by c-Jun N-terminal kinase （JNK）, whereas the phosphory- lation of Bcl-2 at Ser87 is unaffected by palmitate or PKR. In summary, PKR mediates the regulation of the protein level and the phosphorylation status of Bel-2, providing a novel mechanism of palmitate-induced apoptosis in HepG2 cells.
文摘Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both salts whereas uptake of Ca^2＋ retarded mainly by Na2SO4. Chlorophyll content was affected mainly by NaCl, while Na2SO4 treatment lowered the rate of photosynthetic activity. Both salt compounds caused accumulation of free amino acids including free proline but reduced the protein content in the leaves. The salt tolerance capacity of the broad beans plant in which the observations of the effect of salinity determined by different concentrations of NaCI and Na2SO4 on growth, chloroplast pigments, photosynthetic, free amino acids, free proline, protein and inorganic elements on plants are combined with observations on growth and yield, in order to arrive at a better understanding of their salt tolerance, has been studied and discussed in this paper. The results for the latter only （fruiting stage） are presented.
基金Supported by Fund of Education Department of Guangdong Province(cgzhzd0809)Teamwork Projects Funded by Guangdong Natural Science Foundation(S2013030012842)
文摘[Objective] This study was conducted to investigate the effects of light quality on growth and quality of Chinese kale(Brassica alboglabra Bailey). [Method]Chinese kale was grown in hydroponic under three different Light Emitting Diode(LEDs) conditions [red∶blue=8∶1(8R1B), red∶blue=6∶3(6R3B) and red∶green∶blue=6∶2∶1(6R2G1B), 12 h light, 50 μmol/(m2·s)]. Then its growth and quality indices including root and shoot fresh weight and dry weight, concentrations of soluble protein, vitamin C, nitrate, soluble phenols, flavonoids, soluble sugar, free amino acids, and activity of nitrate reductase were measured. [Result] There was no significant difference in plant height, diameter of flower stalk and leaf number among three LED treatments. The fresh weight of shoot, root and plant in 8R1 B and 6R2G1 B was significantly higher than in 6R3 B. The dry weight of shoot and plant in 8R1 B was significantly higher than in 6R3 B. The concentrations of vitamin C, soluble protein and soluble sugar in flower stalk of 6R3 B treatment were significantly higher than those in 8R1 B and 6R2G1 B, while there was no remarkable difference in concentrations of reducing sugar, soluble phenol, flavonoids and free amino acid among the three treatments. The nitrate concentration in flower stalk of 6R3 B was significantly lower than in the other two treatments, and the activity of nitrate reductase in6R3 B was significantly higher than in the other two treatments. [Conclusion] The LED treatment of red:blue=6:3 was more suitable for the growth of Chinese kale.
