Department of Molecular Biotechnology and Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-237 Lodz, Banacha 12/16, Poland
Dr. Katarzyna Hnatuszko-Konka
Department of Molecular Biotechnology and Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-237 Lodz, Banacha 12/16, Poland
Plant biotechnology is a dynamically developing science, which comprises many fields of knowledge. Novel plant genetic engineering findings highly influence the improvement of industrial production. These findings mostly concern cis-regulatory elements, which are sequences controlling gene expression at all developmental stages. They comprise of promoters, enhancers, insulators and silencers, which are used to construct synthetic expression cassettes. Examples of most important cis-regulatory elements are reviewed in the present paper. Variability among core promoters content and distal promoter regions impedes evaluation of interactions between them during the artificial promoters construction. Synthetic promoters and artificial expression cassettes trigger a significant increase in gene expression level, better properties and quality of a product. Accumulating knowledge about gene promoters, cis sequences and their cooperating factors allows uniform expression systems and highly predictable results.
30 November 2014 in Plant Cell, Tissue and Organ Culture (PCTOC)
Originating in the Andes, the tomato (Solanum lycopersicum L.) was imported to Europe in the 16th century. At present, it is an important crop plant cultivated all over the world, and its production and consumption continue to increase. This popular vegetable is known as a major source of important nutrients including lycopene, β-carotene, flavonoids and vitamin C as well as hydroxycinnamic acid derivatives. Since the discovery that lycopene has anti-oxidative, anti-cancer properties, interest in tomatoes has grown rapidly. The development of genetic engineering tools and plant biotechnology has opened great opportunities for engineering tomato plants. This review presents examples of successful tissue culture and genetically modified tomatoes which resistance to a range of environmental stresses improved, along with fruit quality. Additionally, a successful molecular farming model was established.
Tomato is one of the most often cultivated vegetable species worldwide. Due to the anti-oxidative and anti-cancer properties of lycopene, tomato consumption as well as production is still increasing. However, its productivity is impaired by a wide range of abiotic stresses, and the establishment of stress-tolerant crops is a key challenge for agricultural biotechnology. Until now, a few genetic approaches have been used to achieve stress tolerance in cultivated tomato plants. Such achievements are based on current knowledge concerning plant adaptation. The presence of adverse environmental factors like extreme temperatures, salinity or drought cause definite biochemical and physiological consequences. Mostly, these are the changes in the metabolic pathways, the expression of stress-inducible genes or the accumulation of low-molecular compounds that play a crucial role in maintaining the plasticity of reactions. The biotechnological methods used to modify tomato to produce “upgraded” plants are based on introgression of several genes coding enzymes known to mitigate stress or genes contributing to signalling and diverse regulatory pathways. Here, we present an overview of the most often chosen target sequences/molecules that are genetically delivered or engineered to obtain tolerance to environmental constraints. Since adverse conditions cause interrelated stress responses, it is the tolerance molecular players that are consecutively presented in this paper rather than the typically reviewed division of stress types.
4 April 2014 in World Journal of Microbiology and Biotechnology
Elastin-like polypeptides (ELP) are artificial, genetically encodable biopolymers, belonging to elastomeric proteins, which are widespread in a wide range of living organisms. They are composed of a repeating pentapeptide sequence Val–Pro–Gly–Xaa–Gly, where the guest residue (Xaa) can be any naturally occurring amino acid except proline. These polymers undergo reversible phase transition that can be triggered by various environmental stimuli, such as temperature, pH or ionic strength. This behavior depends greatly on the molecular weight, concentration of ELP in the solution and composition of the amino acids constituting ELPs. At a temperature below the inverse transition temperature (Tt), ELPs are soluble, but insoluble when the temperature exceeds Tt. Furthermore, this feature is retained even when ELP is fused to the protein of interest. These unique properties make ELP very useful for a wide variety of biomedical applications (e.g. protein purification, drug delivery etc.) and it can be expected that smart biopolymers will play a significant role in the development of most new materials and technologies. Here we present the structure and properties of thermally responsive elastin-like polypeptides with a particular emphasis on biomedical and biotechnological application.
Recombinant proteins are produced for various applications in laboratory and industrial settings. Among them, therapeutic applications have evolved into a mature field in recent years, affecting the face of contemporary medical treatment. This, in turn, has stimulated an ever-greater need for innovative technologies for the description, expression, and purification of recombinant protein biopharmaceuticals. Therefore, many biopharmaceuticals are synthesized in heterologous systems to obtain satisfactory yields that cannot be provided by natural sources. As more than 35 years has passed since the first recombinant biopharmaceutical (human insulin) successfully completed clinical trials in humans, we provide a brief review of the available prokaryotic and eukaryotic expression systems, listing the advantages and disadvantages of their use. Some examples of therapeutic proteins expressed in heterologous hosts are also provided. Moreover, technologies for the universal extraction of protein molecules are mentioned here, as is the methodology of their purification.
The ability to restore or replace injured tissues can be undoubtedly named among the most spectacular achievements of plant organisms. One of such regeneration pathways is organogenesis, the formation of individual organs from nonmeristematic tissue sections. The process can be triggered in vitro by incubation on medium supplemented with phytohormones. Cytokinins are a class of phytohormones demonstrating pleiotropic effects and a powerful network of molecular interactions. The present study reviews existing knowledge on the possible sequence of molecular and genetic events behind de novo shoot organogenesis initiated by cytokinins. Overall, the review aims to collect reactions encompassed by cytokinin primary responses, starting from phytohormone perception by the dedicated receptors, to transcriptional reprogramming of cell fate by the last module of multistep-phosphorelays. It also includes a brief reminder of other control mechanisms, such as epigenetic reprogramming.