|
|
The role of UDP-glycosyltransferases in herbicide resistance
Mudrová, Dagmar ; Podlipná, Radka (advisor) ; Hála, Michal (referee)
Along with the widespread use of herbicides in modern agriculture, the phenomenon of herbicide resistance has appeared, where weed plants become partially or completely resistant to the action of one or more herbicides. Resistance arises in two ways - by a change in the target molecule on which the herbicide acts, so-called "target site resistance" (TSR), or by a change in other non-target proteins, so-called "non-target site resistance" (NTSR). UDPglycosyltransferases (UGT), which glycosylate a wide range of endogenous plant molecules and xenobiotics, are also involved in NTSR. Also, increased activity of antioxidant enzymes may contribute to NTSR. This work was focused on the interaction of the herbicides pinoxaden and sulcotrione with the model plant Arabidopsis thaliana. The aim of this work was to determine whether some of the selected UGT genes change their expression profile after contact with pinoxaden, and whether these changes are influenced by the contact of plants in previous generations with pinoxaden. The expression of selected UGT genes was also monitored in plants treated with sulcotrione. It was also monitored whether the activity of selected antioxidant enzymes changes in plants that were treated with the herbicide pinoxaden or sulcotrione. The results showed that in the case of...
|
|
|
Plant responses to combined arsenic and cadmium stress
Burešová, Andrea ; Mašková, Petra (advisor) ; Podlipná, Radka (referee)
Arsenic and cadmium are both non-essential, highly toxic and carcinogenic elements that often occur together in the environment. Given the frequent co-contamination of the environment, it is necessary to investigate both plant strategies for dealing with one metal(loid) and the mechanisms that lead to tolerance or, conversely, sensitivity in the presence of both elements. Simultaneous exposure to multiple toxic elements may lead to extensive plant damage, however it may also result in the increasing engagement and intensity of defence strategies. Contamination of the food chain through crops growing on contaminated soils is a major concern, one that poses a risk to both human and animal lives. The aim of this research field is to reduce accumulation and translocation to aboveground edible parts as much as possible, for example by understanding the mechanisms behind heavy metal accumulation and translocation, or by stabilising toxic elements in the soil, or by cleaning up contaminated soil. One method of clean-up is phytoremediation, which usually utilizes plants with high tolerance to toxic elements, called hyperaccumulators. The knowledge of how defence strategies and mechanisms are affected by the interaction of multiple elements is important for identifying plant species capable of activating...
|
|
|
The effect of heavy metals on plant carbohydrate metabolism
Kofroňová, Monika ; Lipavská, Helena (advisor) ; Podlipná, Radka (referee)
Arsenic is an element which belongs to metaloids. Contamination with arsenic is a problem all over the world. Basically it is a part of Earth's crust, but with anthropogenic activities it could overspread into soil, water and air in large scale a thus it could mean health hazard. Fytoremediation is kind of environment decontamination, which is quite effective and cheap as well. Publications about arsenic and its influence on plant metabolism are mostly focused on important crop plants like rice. Rice is mostly used for experiments and questions on anatomical and morphological changes are widely being solved by these experiments, but it has only insignificant relevance for fytoremediation. There are only few publications about arsenic influence on carbohydrate metabolism, thus little is known about this problem. That is why I have decided to study this topic more deeply and get more information about carbohydrate metabolic changes under influence of arsenic and partly also under influence of mercury, because information about influence of mercury are completely lacking. My experimental material includes tobacco plant, tobacco tissue cultures and horseradish hairy roots cultures. Accumulation of starch and soluble carbohydrate spectrum and content was determined by HPLC. Furthermore arsenic influence...
|
|
|
New pharmacological interventions influencing food intake regulation
Špolcová, Andrea ; Čabala, Radomír (advisor) ; Podlipná, Radka (referee)
NEW PHARMACOLOGICAL INTERVENTIONS INFLUENCING FOOD INTAKE REGULATION Author: Bc. Andrea Špolcová ABSTRACT Prolactin-releasing peptide (PrRP) identified as an endogenous ligand of the orphan receptor GPR10 was originally found to stimulate the secretion of prolactin (PRL) both in vitro and in vivo. PrRP-mediated PRL secretion was later questioned and is not currently considered to be the primary function of PrRP. The fact that both PrRP and GPR10 knock-out mice are hyperphagic and develop late-onset obesity proves the unique anorexigenic properties of PrRP. Designing and evaluation of PrRP analog(s) with selective anorexigenic properties and searching for PrRP antagonists would contribute to finding the mechanism and possible treatment of obesity and metabolic syndrome. In our recent published study (Maixnerová et al., Peptides (2011)), the PrRP receptor was immunodetected and characterized by saturation binding in three rodent tumor pituitary cell lines. Two naturally occurring analogs, PrRP31 and PrRP20, showed comparable potency in binding, cell signaling and prolactin release in pituitary RC-4B/C cells, as well as caused food intake decrease after intracerebroventricular administration in fasted mice. In the present study, analogs of PrRP20 with C-terminal Phe amide derivatives with modified aromatic...
|
|
|
Study of plant stress responces in presence of pharmaceuticals in cultivation medium
Bystroňová, Jana ; Soudek, Petr (advisor) ; Podlipná, Radka (referee)
The aim of this study was to verify the possibility of ibuprofen degradation by selected plant cultures and determination of activities of antioxidant enzymes (peroxidase, catalase, ascorbate peroxidase and glutathione-S-transferase) as markers of oxidative stress caused by ibuprofen. Nicotiana tabaccum (cv. La Burley 21, cv. SR 1 and their GMOs) and Nicotiana glauca were used as experimental plants. The rate of removal of ibuprofen tested by tobacco was decreasing in the following order: N. tabaccum SR1 > N. tabaccum Zm-P60-1-T4 > N. tabaccum TRI 2T2 > N. glauca > N. tabaccum TRI 2T1 > N. tabaccum cv. La Burley > N. tabaccum Zm-P60-1-T5. As the most suitable tobacco for the removal of ibuprofen seemed untransformed N. tabaccum SR1. The long-term experiment showed that plant stress is being manifested even after longtime. N. tabaccum cv. La Burley 21 seemed to be the most tolerant to ibuprofen in compare with the total enzyme activities in cultures with the presence of ibuprofen and controls. N.glauca was the least tolerant cultivar. Keywords: phytoremediation, ibuprofen, Nicotiana tabaccum, Nicotiana glauca, HPLC, peroxidase, catalase, ascorbate peroxidase, glutathion-S-transferase
|
|
| |
|
|
Thorium as an environment stressor for plant growth.
Hrdinová, Aneta ; Lhotáková, Zuzana (advisor) ; Podlipná, Radka (referee)
Thorium is an element belonging to heavy metals, which is characterized by its radioactivity similarly to uranium and radon. Thorium is not commonly used in industry, but becouse of its radioactive properties it has a great potentional for future use in nuclear energetics. Thus, increasing release of Th into the soil, water and atmosphere can be expected in near future and through plant biomass it could become a part of food chains and webs and, thus, to represent a considerable health risks to humans. Studies devoted to research on thorium and its effects on plants has not been published much yet. The majority of these studies focus mainly only on plant abilities to accumulate thorium and/or monitoring distribution of thorium in plant body. But till now, a study is still missing, which would monitor the effect of thorium on the physiological characteristics of plants. Plants of Nicotiana glutinosa (L.) medium Thorium accumulatin were hydroponically cultivated Hoagland nutrient media differedin the presence of thorium, tartaric acid, putrescine and phosphates. In first part of the present study I monitored accumulation of thorium by tobacco plants under the influence of the above-mentioned modifications of media. In the second part, I studied the Th effect on the photosynthetic apparatus (contents...
|
|
| |
|
| |
|
|
Arsenic toxicity and hyperaccumulation in plants and their potentail use in phytoremediation
Gímeš, Lukáš ; Mašková, Petra (advisor) ; Podlipná, Radka (referee)
Arsenic is classified as a heavy metalloid. Small amounts of arsenic can be found in the environment naturally, but human activity constantly increases the amount of arsenic in the soil. Increasing arsenic contamination of the soil causes serious health problems for both animals and humans. Due to its toxicity, it can also cause considerable problems for plants. Arsenic negatively affects a number of processes in the body of plants, such as oxidative stress or the metabolism of important macromolecules. Photosynthesis is a physiological process that is the most affected by arsenic toxicity. Closely related to photosynthesis are the growth properties of plants. Negative effects that arsenic has on many biochemical, physiological and morphological processes in the plant body, we must understand the uptake, translocation and detoxification of arsenic in the plant body. Arsenic hyperaccumulators are plants that can accumulate orders of magnitude higher concentrations of As and better manage the phytotoxicity of this contaminant than non-hyperaccumulating plants. Hyperaccumulation of heavy metals is associated with changes in the physiological properties of plants. A common characteristic of hyperaccumulators is that they can accumulate the higher concentrations of metals they in the aboveground parts...
|
guest ::
