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81.
Sonia Gómez-Galera Eduard Rojas Duraialagaraja Sudhakar Changfu Zhu Ana M. Pelacho Teresa Capell Paul Christou 《Transgenic research》2010,19(2):165-180
Staple food crops, in particular cereal grains, are poor sources of key mineral nutrients. As a result, the world’s poorest
people, generally those subsisting on a monotonous cereal diet, are also those most vulnerable to mineral deficiency diseases.
Various strategies have been proposed to deal with micronutrient deficiencies including the provision of mineral supplements,
the fortification of processed food, the biofortification of crop plants at source with mineral-rich fertilizers and the implementation
of breeding programs and genetic engineering approaches to generate mineral-rich varieties of staple crops. This review provides
a critical comparison of the strategies that have been developed to address deficiencies in five key mineral nutrients—iodine,
iron, zinc, calcium and selenium—and discusses the most recent advances in genetic engineering to increase mineral levels
and bioavailability in our most important staple food crops. 相似文献
82.
Pooja Mehta Anjana Jajoo Sonal Mathur Sudhakar Bharti 《Plant Physiology and Biochemistry》2010,48(1):16-20
In order to study the effects of high salt stress on PS II in detached wheat (Triticum aestivum) leaves, the seedlings were grown in Knop solution and temperature was 20 ± 2 °C. Detached leaves were exposed to high salt stress (0.1–0.5 M NaCl) for 1 h in dark and Chl a fluorescence induction kinetics was measured. Various parameters like Fv/Fm, ABS/RC, ETo/TRo, performance index and area over the florescence curve were measured and the energy pipeline model was deduced in response to salt stress. Our results show that the damage caused due to high salt stress is more prominent at the donor side rather than the acceptor side of PS II. Moreover the effects of high salt stress are largely reversible, as the acceptor side damage is completely recovered (~100%) while the recovery of the donor side is less than 85%. Based on our results we suggest that in response to high salt stress, the donor side of PS II is affected more as compared to the acceptor side of PS II. 相似文献
83.
Prabakaran Ravichandran Sudhakar Baluchamy Bindhu Sadanandan Ramya Gopikrishnan Santosh Biradar Vani Ramesh Joseph C. Hall Govindarajan T. Ramesh 《Apoptosis : an international journal on programmed cell death》2010,15(12):1507-1516
Our previous report on multiwall carbon nanotubes (MWCNT) has demonstrated the generation of reactive radicals and depletion
of intracellular antioxidants which in turn cause cell death through activation of caspases. The molecular mechanism of cellular
death due to MWCNT is not clear yet. In this study, we investigated the signaling pathways implicated in MWCNT-induced apoptosis
in rat lung epithelial cells. First, we assessed the DNA damage in response to MWCNT treatment and showed the significant
DNA damage as compared to control. The collapse of the mitochondrial membrane integrity, release of cytochrome c into the
cytosol, reduction in cellular ATP content, increased levels of mitochondrial apoptogenic factor and activation and nuclear
translocation of NF-κB were observed in MWCNT treated cells. In addition, a time-dependent induction of phosphorylated IκBα and its degradation
were detected in cells exposed to MWCNT. Furthermore, MWCNT activated several death related proteins including apoptosis inducing
factor, p53, p21 and bax. Together, our results suggest that signaling pathways such as NF-κB and AP-1 are activated upon MWCNT treatment for cellular cytotoxicity. 相似文献
84.
Nalini Eswaran Sriram Parameswaran Balaji Sathram Bhagyam Anantharaman Raja Krishna Kumar G Sudhakar Johnson Tangirala 《BMC biotechnology》2010,10(1):23
Background
Environmentally inflicted stresses such as salinity and drought limit the plant productivity both in natural and agricultural system. Increasing emphasis has been directed to molecular breeding strategies to enhance the intrinsic ability of plant to survive stress conditions. Functional screens in microorganisms with heterologous genes are a rapid, effective and powerful tool to identify stress tolerant genes in plants. Jatropha curcas (Physic nut) has been identified as a potential source of biodiesel plant. In order to improve its productivity under stress conditions to benefit commercial plantations, we initiated prospecting of novel genes expressed during stress in J. curcas that can be utilized to enhance stress tolerance ability of plant. 相似文献85.
Sabyasachi Bhattacharya Wei-Chun HuangFu Jianghuai Liu Sudhakar Veeranki Darren P. Baker Constantinos Koumenis J. Alan Diehl Serge Y. Fuchs 《The Journal of biological chemistry》2010,285(4):2318-2325
Phosphorylation-dependent ubiquitination and ensuing down-regulation and lysosomal degradation of the interferon α/β receptor chain 1 (IFNAR1) of the receptor for Type I interferons play important roles in limiting the cellular responses to these cytokines. These events could be stimulated either by the ligands (in a Janus kinase-dependent manner) or by unfolded protein response (UPR) inducers including viral infection (in a manner dependent on the activity of pancreatic endoplasmic reticulum kinase). Both ligand-dependent and -independent pathways converge on phosphorylation of Ser535 within the IFNAR1 degron leading to recruitment of β-Trcp E3 ubiquitin ligase and concomitant ubiquitination and degradation. Casein kinase 1α (CK1α) was shown to directly phosphorylate Ser535 within the ligand-independent pathway. Yet given the constitutive activity of CK1α, it remained unclear how this pathway is stimulated by UPR. Here we report that induction of UPR promotes the phosphorylation of a proximal residue, Ser532, in a pancreatic endoplasmic reticulum kinase-dependent manner. This serine serves as a priming site that promotes subsequent phosphorylation of IFNAR1 within its degron by CK1α. These events play an important role in regulating ubiquitination and degradation of IFNAR1 as well as the extent of Type I interferon signaling. 相似文献
86.
Keshamouni VG Michailidis G Grasso CS Anthwal S Strahler JR Walker A Arenberg DA Reddy RC Akulapalli S Thannickal VJ Standiford TJ Andrews PC Omenn GS 《Journal of proteome research》2006,5(5):1143-1154
Transforming growth factor-beta (TGF-beta) induces epithelial-mesenchymal transition (EMT) of epithelial cells in both normal embryonic development and certain pathological contexts. Here, we show that TGF-beta induced-EMT in human lung cancer cells (A549; adenocarcinoma cells) mediates tumor cell migration and invasion phenotypes. To gain insights into molecular events during EMT, we employed a global stable isotope labeled profiling strategy using iTRAQ reagents, followed by 2DLC-MS/MS, which identified a total of 51 differentially expressed proteins during EMT; 29 proteins were up-regulated and 22 proteins were down-regulated. Down-regulated proteins were predominantly enzymes involved in regulating nutrient or drug metabolism. The majority of the TGF-beta-induced proteins (such as tropomyosins, filamin A, B, & C, integrin-beta1, heat shock protein27, transglutaminase2, cofilin, 14-3-3 zeta, ezrin-radixin-moesin) are involved in the regulation of cell migration, adhesion and invasion, suggesting the acquisition of a invasive phenotype. 相似文献
87.
88.
The reversibility of nitrite-induced inhibition in relation to energy distribution between the two photosystems was studied in spinach thylakoid membranes. Measurements of electron transfer rate catalyzed by photosystem I (PS I) and photosystem II (PS II), chlorophyll a (Chl a ) fluorescence induction kinetics, S2 state multiline spectra, and room temperature electron paramagnetic resonance (EPR) signals indicated that nitrite anions bind PS II in two ways: dissociable (loose) and non-dissociable (tight). The inhibition caused by the dissociable binding was reversible in washed (nitrite-treated samples washed with nitrite-free medium) samples, while the inhibition caused by the non-dissociable binding was irreversible. At 77 K, an increase in absorption cross section of PS I (as inferred from the excitation spectra of Chl a fluorescence) and a decrease in absorption cross section of PS II in nitrite-treated sample when compared with sample washed with nitrite-free medium and control sample suggested that nitrite plays a role in regulating the distribution of absorbed excitation energy between the two photosystems. We propose, for the first time, that the removal of loosely bound nitrite leads to migration of light-harvesting complex II back to the PS II, and thus the mode of binding of nitrite regulates the extent of migration of antenna molecules between the two photosystems. 相似文献
89.
90.
Babu TS Akhtar TA Lampi MA Tripuranthakam S Dixon DG Greenberg BM 《Plant & cell physiology》2003,44(12):1320-1329
Metals and ultraviolet (UV) radiation are two environmental stressors that can cause damage to plants. These two types of stressors often impact simultaneously on plants and both are known to promote reactive oxygen species (ROS) production. However, little information is available on the potential parallel stress responses elicited by metals and UV radiation. Using the aquatic plant Lemna gibba, we found that copper and simulated solar radiation (SSR, a light source containing photosynthetically active radiation (PAR) and UV radiation) induced similar responses in the plants. Both copper and SSR caused ROS formation. The ROS levels were higher when copper was combined with SSR than when applied with PAR. Higher concentrations of copper plus PAR caused toxicity as monitored by diminished growth and chlorophyll content. This toxicity was more pronounced when copper was combined with SSR. Because the generation of ROS was also higher when copper was combined with SSR, we attributed this enhanced toxicity to elevated levels of ROS. In comparison to PAR-grown plants, SSR treated plants exhibited elevated levels of superoxide dismutase (SOD) and glutathione reductase (GR). These enzyme levels were further elevated under both PAR and SSR when copper was added at concentrations that generated ROS. Interestingly, copper treatment in the absence of SSR (i.e. copper plus PAR) induced synthesis of the same flavonoids as those observed in SSR without copper. Finally, addition of either dimethyl thiourea or GSH (two common ROS scavengers) lowered in vivo ROS production, alleviated toxicity and diminished induction of GR as well as accumulation of UV absorbing compounds. Thus, the potential of ROS being a common signal for acclimation to stress by both copper and UV can be considered. 相似文献