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1

Physiological and metabolic enzymes activity changes in transgenic rice plants with increased phosphoenolpyruvate carboxylase activity during the flowering stage

100%

Xia L., Cao W.

Acta Physiologiae Plantarum

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2013

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tom 35

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nr 05

To compare the differences in physiology and metabolism between phosphoenolpyruvate carboxylase (PEPC) transgenic rice and its control, untransformed wild rice, dry matter accumulation, soluble sugar, starch and protein contents and enzyme activities were determined in different plant parts during flowering. Results revealed that PEPC transgenic rice had higher dry weights for leaf, stem and sheath as well as panicle than the untransformed wild rice did, with the largest increase in the panicle. Soluble sugar and protein content in the grains of PEPC transgenic rice were significantly enhanced while starch content changed less. PEPC transgenic rice exhibited high levels of PEPC activity, manifesting in high net photosynthetic rates during flowering. Moreover, transgenic rice with high PEPC expression levels also had elevated levels of the enzymes such as sucrose-p-synthase and sucrose synthase, which may confer a higher capacity to assimilate CO2 into sucrose. Little increase in grain starch content was observed in transgenic plants due to the stable activities of starch synthase and Q enzyme. However, the PEPC transgenic rice plant induced the activities of nitrate reductase, glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, glutamine synthetase, and asparagine synthase to high levels, as compared with the untransformed rice plant. PEPC activity was correlated with protein content in grains and the enzymes of nitrogen metabolism, suggesting that high PEPC activity in transgenic rice might be able to redirect carbon and nitrogen flow by regulating some enzymes related to carbon or nitrogen metabolisms. These results may help to understand how the C3 plants possessing a C4-like photosynthesis pathway worked by expression of PEPC.

2

Salt priming improved salt tolerance in sweet sorghum by enhancing osmotic resistance and reducing root Na+ uptake

81%

Yan K., Xu H., Cao W., Chen X.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 10

This study attempted to explore how salt priming affected salt tolerance in sweet sorghum with emphasis on root Na+ uptake. After 10 days of pretreatment with 150 mM NaCl, plants were stressed with 300 mM NaCl. After salt stress for 7 days, dry matter of root and shoot decreased by 58.7 and 69.7 % in non-pretreated plants and by 37.9 and 41.3 % in pretreated plants. Consistently, pretreated plants maintained higher photosynthetic rate during salt stress, suggesting the enhanced tolerance by salt priming. Salt priming enhanced osmotic resistance, as proline and relative water contents in the leaf were higher in pretreated plants under salt stress. Salt priming alleviated salt-induced oxidative damage not by improving antioxidant protection due to lower increase in leaf malondialdehyde content and no extra induction on ascorbate peroxidase, catalase, superoxide dismutase,ascorbic acid and reduced glutathione in pretreated plants. After 7 days of salt stress, root Na+ efflux increased by 8.5- and 3.9-folds in pretreated and non-pretreated plants, suggesting that salt priming reduced root Na+ uptake, and then root and leaf Na+ accumulation were mitigated in pretreated plants. However, root Na+ extrusion became indifferent between pretreated and non-pretreated plants under salt stress after inhibiting plasma membrane (PM) Na+/H+ antiporter. Thus, the greater Na+ extrusion induced by salt priming had relation to PM Na+/H+ antiporter. Overall, salt priming improved salt tolerance in sweet sorghum by enhancing osmotic resistance and reducing root Na+ uptake.

3

Comparisons of cadmium tolerance and accumulation at seedling stage in wheat varieties grown in different decades in China

71%

Ci D., Jiang D., Liu F., Dai T., Cao W.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 5

Cadmium (Cd) tolerance and accumulation in wheat varieties were investigated at seedling stage under a controlled environmental condition. The 46 leading wheat varieties cultivated from the 1950s to 2000s in China were treated at the three-leaf stage with a 50 µM CdCl₂ solution for 24 days. Growth and photosynthesis parameters were measured and the Cd-tolerance index (ratio of a given parameter under Cd treatment to that of the control) was determined. Cd accumulation in shoots and roots and Cd translocation were also determined. It was found that Cd tolerance and accumulation of these wheat varieties varied over the different decades. Principal components analysis (PCA) showed that wheat varieties in 1950s and 1980s were tolerant while varieties from the last decade were sensitive to Cd stress. Wheat varieties in 1960s and 1970s were particularly tolerant to Cd stress for the parameters of shoot height, secondary root numbers, net photosynthesis and transpiration rate while the varieties in the 1990s were sensitive to Cd stress for shoot dry weight and root dry weight. Comparing each decade to the average Cd translocation ratio from the roots to the shoots for the whole period, the varieties from the 1950s and 1960s had a higher translocation ratio, while varieties in the 1970s were below that average. Varieties from the 1980s to 2000s showed an average translocation ratio. Using cluster analysis (CA), Shannongfu 63, Yangmai 1 and Yangmai 158 were the most Cd-tolerant varieties in which Cd translocation ratio were low, and Yumai 18 and Huaimai 20 were the most Cd-sensitive varieties in which Cd translocation ratio were high. The results indicating that wheat varieties from different decades were different in Cd tolerance and accumulation, and could be useful for breeding wheat for Cd stress tolerance.

4

DNA constructs designed to produce short hairpin, interfering RNAs in transgenic mice sometimes show early lethality and an interferon response

71%

Cao W., Hunter R., Strnatka D., McQueen C. A., Erickson R. P.

Journal of Applied Genetics

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2005

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tom 46

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nr 2

Arylamine N-acetyltransferase (NAT) genes were targeted for inhibition using short hairpin RNA (shRNA) using two different RNA polymerase III promoters. Constructs were developed for NAT1 and NAT2, the endogenous mouse genes, and for human NAT1. There were fetal and neonatal deaths with these constructs, perhaps due in part to an interferon response as reflected in increases in oligoadenylate synthetase I mRNA levels. Seven out of 8 founders with the U6 promoter generated offspring but only 2 gave positive offspring. Out of 15 founders for H1 promoted constructs, only 4 had positive offspring. When transgenic lines were successfully established, the expression of the targeted genes was variable between animals and was not generally inhibitory.

5

Cadmium stress in wheat seedlings: growth, cadmium accumulation and photosynthesis

61%

Ci D., Jiang D., Wollenweber B., Dai T., Jing Q., Cao W.

Acta Physiologiae Plantarum

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2010

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tom 32

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nr 2

Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50 μM of CdCl₂ in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas exchange, and Cd accumulation in wheat seedlings were investigated. Gas exchange was monitored at 3, 9, 24 days after treatment (DAT). Growth parameters, chlorophyll content, leaf chlorophyll fluorescence, and Cd concentration in shoot and root were measured at 24 DAT. Seedling growth, gas exchange, chlorophyll content, chlorophyll fluorescence parameters were generally depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis and fluorescence and corrected Cd concentrations in shoots and roots could be explained by the regression model Y = K/(1 + exp(a + bX)). Jing 411 was found to be Cd tolerant considering parameters of chlorophyll content, photosynthesis and chlorophyll fluorescence in which less Cd translocation was from roots into shoots. The high Cd concentrations were in shoots and roots in Yangmai 10 which has been found to be a relative Cd tolerant cultivar in terms of most growth parameters.

6

Identification of quantitative trait loci for cadmium tolerance and accumulation in wheat

61%

Ci D., Jiang D., Li S., Wollenweber B., Dai T., Cao W.

Acta Physiologiae Plantarum

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2012

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tom 34

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nr 1

Quantitative trait loci (QTL) for Cadmium (Cd) tolerance and accumulation in wheat (Triticum aestivum L.) were identified, using 103 recombinant inbred lines (RILs) derived from a cross of Ch × Sh at germination and seedling stages. The traits of germination, growth and physiology were measured. Cd tolerance indexes (TI) were calculated for plants under Cd stress relative to control conditions. Cd concentrations in both root and shoot were determined and the amount of Cd accumulation and translocation calculated. The phenotypic variation of the above traits showed a continuous distribution pattern among the RILs. Twenty-six QTLs were detected, (16 of which were designated for the traits under the control and Cd stress, 8 for Cd tolerance and 2 for root Cd accumulation). These 26 QTLs individually could explain 7.97–60.16% of the phenotypic variation. Fourteen QTLs were positive (with the additive effects coming from Ch) while the remaining 12 QTLs were negative (with the additive effects contributed by Sh). No QTL were detected in the same region on the chromosomes of wheat. The results indicated that genetic mechanisms controlling the traits of Cd tolerance were independent from each other. Therefore, in this study, the properties of Cd tolerance and accumulation showed to be independent traits in wheat.

7

Effect of spermine on liver and spleen antioxidant status in weaned rats

61%

Liu G., Cao W., Jia G., Zhao H., Chen X., Wang J., Wu C.

Journal of Animal and Feed Sciences

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2016

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tom 25

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nr 4

Whereas strong antioxidant properties of spermine have been reported mostly in in vitro studies, there is lack of the in vivo studies on spermine influence conducted on mammals. The main objective of this study was to investigate the effects of different doses of spermine and the period of its supplementation on the liver and spleen antioxidant capacity in weaned rats. Male Sprague-Dawley rats at the age of 19 days received intragastrically spermine at the dose of 0.2 or 0.4 μmol · g-1 body weight for 3 or 7 days, respectively. Control rats received saline in analogical way. It was found that liver anti-superoxide anion (ASA) capacity, catalase (CAT) activity, glutathione (GSH) content and total antioxidant capacity (T-AOC) were increased in group supplemented with higher dose of spermine after 3 days, and anti-hydroxy radical (AHR) capacity was increased when treatment lasted for 7 days. In the spleen the higher spermine dose supplementation increased ASA capacity and total superoxide dismutase (T-SOD) activity (after 3 and 7 days), AHR capacity (after 7 days) and T-AOC (after 3 days) in comparison to the corresponding control groups (P < 0.05). Only in the spleen the lower spermine dose reduced lipid peroxidation level and increased CAT activity and GSH content regardless treatment duration (P < 0.05). The obtained results suggest that spermine supplementation can improve the antioxidant properties of the liver and spleen of weaned rats in a dose-, time- and tissue-dependent manner.

8

Spatial pattern of the planktonic ciliate community and its relationship with the environment in spring in the Northern Beibu Gulf, South China Sea

61%

Wang Y., Zhang W., Lin Y., Zheng L., Cao W., Yang J.

Oceanological and Hydrobiological Studies

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2013

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tom 42

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nr 4

9

Effect of water deficit during vegetative growth periods on post-anthesis photosynthetic capacity and grain yield in winter wheat (Triticum aestivum L.)

51%

Ciu Y., Tian Z., Zhang X., Muhammad A., Han H., Jiang D., Cao W., Dai T.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 10

Determining the effect of water deficit during vegetative growth periods on grain yield will provide reasonable strategy for water-saving management of winter wheat (Triticum aestivum L.). Pot experiment was conducted using winter wheat cultivar (Yangmai16) to investigate the effects of water deficit during vegetative periods on post-anthesis photosynthetic capacity and the relationship with grain yield formation during the growing season of 2013–2014. Water deficit consisted of moderate (leaf water potential of -1.20 to -1.40 MPa) and severe (leaf water potential of -1.80 to -2.20 MPa) levels during tillering and jointing growth stages, respectively. Moderate water deficit during tillering significantly increased grain yield through an enhanced yield capacity per stem and moderate water deficit during jointing resulted in similar grain yields as compared to control, while severe water deficit during both periods significantly reduced grain yield due to strong reduction in number of spikes as compared to control. Moderate or severe water deficit during tillering had no effect on flag leaf area but reduced it significantly when it occurred during jointing. Water deficit treatments during jointing and tillering increased net photosynthetic rate (Pn) of flag leaves, the treatment during jointing being the most stimulatory. The maximum photochemical efficiency of Photosystem II, actual photochemical efficiency, the maximum carboxylation rate and photosynthetic electron transport rate increased in ways similar to Pn in response to water deficit but non-photochemical quenching decreased. We conclude that improved photosynthetic capacity by moderate water deficit during vegetative growth period highly contributes to grain yield, especially during tillering period, while grain yield decreased by the limitation of leaf area and spikes under severe water deficit.

Ograniczanie wyników

Physiological and metabolic enzymes activity changes in transgenic rice plants with increased phosphoenolpyruvate carboxylase activity during the flowering stage

Salt priming improved salt tolerance in sweet sorghum by enhancing osmotic resistance and reducing root Na+ uptake

Comparisons of cadmium tolerance and accumulation at seedling stage in wheat varieties grown in different decades in China

DNA constructs designed to produce short hairpin, interfering RNAs in transgenic mice sometimes show early lethality and an interferon response

Cadmium stress in wheat seedlings: growth, cadmium accumulation and photosynthesis

Identification of quantitative trait loci for cadmium tolerance and accumulation in wheat

Effect of spermine on liver and spleen antioxidant status in weaned rats

Spatial pattern of the planktonic ciliate community and its relationship with the environment in spring in the Northern Beibu Gulf, South China Sea

Effect of water deficit during vegetative growth periods on post-anthesis photosynthetic capacity and grain yield in winter wheat (Triticum aestivum L.)