Authors:Y. Li, K. Zhou, M. Jiang, B. Zhang, M. Aslam, and H. Zou
Numerous studies showed that lipid transfer proteins (LTPs) play important roles in flower, development, cuticular wax deposition and pathogen responses; however, their roles in abiotic stresses are relatively less reported. This study characterized the function of a maize LTP gene (ZmLTP3) during drought stress. ZmLTP3 gene was transferred into maize inbred line Jing2416; subsequently the glyphosate and drought tolerance of the over-expression (OE) lines were analyzed. Analysis showed that OE lines could significantly enhance drought tolerance. Transgenic maize lines OE6, OE7 and OE8 showed lower cell membrane damage, higher chlorophyll contents, higher protective enzymes activities, better growth and development under drought condition. The results strongly indicated that overexpression of ZmLTP3 could increase drought tolerances in maize.
Iron deficiency is the most common nutritional disorder, affecting over 30% of the world’s human population. The primary method used to alleviate this problem is nutrient biofortification of crops so as to improve the iron content and its availability in food sources. The over-expression of ferritin is an effective method to increase iron concentration in transgenic crops. For the research reported herein, sickle alfalfa (Medicago falcata L.) ferritin was transformed into wheat driven by the seed-storage protein glutelin GluB-1 gene promoter. The integration of ferritin into the wheat was assessed by PCR, RT-PCR and Western blotting. The concentration of certain minerals in the transgenic wheat grain was determined by inductively coupled plasma-atomic emission spectrometry, the results showed that grain Fe and Zn concentration of transgenic wheat increased by 73% and 44% compared to nontransformed wheat, respectively. However, grain Cu and Cd concentration of transgenic wheat grain decreased significantly in comparison with non-transformed wheat. The results suggest that the over-expression of sickle alfalfa ferritin, controlled by the seed-storage protein glutelin GluB-1 gene promoter, increases the grain Fe and Zn concentration, but also affects the homeostasis of other minerals in transgenic wheat grain.
Authors:Z.Y. Yang, C.Y. Liu, Y.Y. Du, L. Chen, Y.F. Chen, and Y.G. Hu
Magome , H. , Yamaguchi , S. , Hanada , A. , Kamiya , Y. , Oda , K.
2004 . Dwarf and delayed-flowering 1 . A novel Arabidopsis mutant deficient in gibberellin biosynthesis because of overexpression of a putative AP2 transcription
-dependent, chromosomally mediated β-lactamases (L1 and L2) [ 14, 18 ]. In addition, a resistant phenotype may be expressed through a multitude of other mechanisms, e.g., lipopolysaccharide-changes or modifying enzymes for aminoglycosides, or through the over-expression of
Nowadays, identification of the novel physio-biological and therapeutic functions of plant cysteine proteinase inhibitors “plant cystatins / phytocystatins” are the great of interests for molecular biologists. Whether for biochemical, structural or functional studies, their successful expression along with an easy purification method is required. To date, fusion tags are the best available tools that meet all those requirements. We report here the cloning and simple functional expression and purification of a barley putative cystatin in Escherichia coli cells. For the first time, a part of barley coding sequence containing a predicted active cystatin was amplified by polymerase chain reaction and expressed as maltose binding fusion protein in TB1 strain of E. coli cells using pMALc2X over-expression vector system without affecting the bacterial growth. The expressed product was purified by single step affinity chromatography from the soluble fraction of induced culture at a yield of about 37 mg/ liter of bacterial cell culture. The purified fused protein could efficiently inhibit papain activity in vitro without the cleavage of the fusion partner.
Authors:R. Lucas, M. Rodríguez-Quijano, J. Vázquez, and J. Carrillo
The effects of environment and the high molecular weight glutenins on some quality properties (sedimentation volume, % protein content, and starch pasting viscosity) of bread wheat mutant waxy lines were evaluated. Thirty-eight 100% amylose-free F
lines were used. The results indicated that the environment did not influence sedimentation volume, mixograph parameters and starch viscosity parameters of waxy flour. Variation in the % protein content was determined mainly by the environment. The sedimentation volume and the mixograph peak development time were influenced by the variation at over expression of Bx7 and the mixograph peak development time was influenced by the
locus. One starch viscosity parameter, time to peak viscosity, was influenced by variation at the
locus. This parameter is significantly lower in the waxy lines than the parent line, which shows the influence of the waxy loci. No significant correlation was observed for sedimentation volume, mixograph parameters, protein content and viscosity parameters of waxy lines.
Wheat is one of the staple food crops in major areas of the world providing the required carbohydrate and proteins in our diet. A decrease in the total yield of wheat has been observed worldwide due to elevation in environmental temperature. Heat stress causes pollen sterility, drying of stigmatic fluid, pseudo-seed setting, empty pockets in endosperm and shrivelled seeds in wheat. Every plant system has defence mechanisms to cope up with the different environmental challenges. The defence mechanisms of wheat consist of heat responsive miRNAs, signalling molecules, transcription factors and stress associated proteins like heat shock proteins (HSPs), antioxidant enzymes etc. Wheat is sensitive to heat stress especially in stages like pollination to milky dough kernel stages is critical for growth and development. Heat stress causes an oxidative burst inside cell system followed by increase in the expression of various proteins like protein kinases, HSPs and antioxidant enzymes. These stress proteins modulate the defence mechanisms of wheat by protecting the denaturation and aggregation of nascent proteins involved in various metabolic reactions. Genetic variation has been observed with respect to expression and accumulation of these stress proteins. Exogenous treatment of various hormones, signalling molecules and chemicals has been reported to enhance the thermotolerance level of wheat under heat stress. Tools of genetic engineering have been also used to develop wheat transgenic lines with over-expression of stress proteins under heat stress condition. There is an arduous task in front of breeders and molecular biologists to develop a climate smart wheat crop with sustainable yield under the threat of global climate change.
Authors:R. M. Babu, R. Velazhahan, P. Vidhyasekaran, K. Seetharaman, and A. Sajeena
. (1997): Overexpression of an endogeneous thionin enhances resistance of Arabidopsis against Fusarium oxysporum. Plant Cell 9, 509-520.
Overexpression of an endogeneous thionin enhances resistance of Arabidopsis against
Authors:L.L. Han, W.G. Xu, L. Hu, Y. Li, X.L. Qi, J.H. Zhang, H.F. Zhang, and Y.X. Wang
.Z., Yu, Y.X., Izui, K., Chen, L.M. 2012. Simultaneous over-expression of citrate synthase and phosphoenolpyruvate carboxylase in leaves augments citrate exclusion and Al resistance in transgenic tobacco. Plant Mol. Biol, Reporter 30 :992