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Chromatin modifications in association with priming phenomenon in plants
Marková, Hana ; Holá, Dana (advisor) ; Fischer, Lukáš (referee)
Plants are exposed to many stressors to which they must be able to adapt. It has been found that plants can memorize the respective stress response and may respond to a subsequent stress exposure faster and to a greater extent. The mechanism of this so-called priming could be associated with the changes in the levels of chromatin modifications. Chromatin modifications are usually dynamically changing during the stress reaction. Some of these changes could persist for some time, thus the specific stress memory, mitotically and meiotically transmissible, could be established. Such a phenomenon was observed for stress caused by dehydration, salinity, mechanical damage, a combination of various stressors and a systemic resistance to pathogenic bacteria. So far, only a few studies on this topic exist; but even now it is clear that there are differences in the response of specific genes as well as the dependence on the length of the stress stimulus and the duration of the period between the first and second stress. A major disadvantage of existing studies is that they focus solely on histone modifications. Regarding the chromatin modifications studied so far, H3K4me3 could serve as the main mark for such priming. On the other hand, H3K27me3 modification is apparently not used as a memory tag. However, it is still...
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Plant - insect interactions in lower Miocene of Central Europe: palaeoclimatological and palaeoecological implications
Knor, Stanislav ; Prokop, Jakub (advisor) ; Kvaček, Jiří (referee) ; Mikuláš, Radek (referee)
The paleoecology of plant - arthropod herbivory associations constitute very important source of knowledge about the phylogeny and co-evolution of both groups. The traces of herbivory interactions between plants and arthropods on the fossil leaves are preserved as so called damaged types (DTs) clustered into distinct functional feeding groups (FFGs). The diversity and frequency of these damage traces also seem to have been strongly influenced by environmental and climatic conditions. This research has been focused on rich fossil plant assemblages from the area of the Most Basin in the north-western Bohemia. The undergoing work has comprised the diagnosis of the individual damages on the basis of their specific morphological traits as their number, size, shape and distributional pattern on the leaf surface. The next issue has involved the statistical analyses concerning the differences in the frequency and diversity of the types of damage and functional feeding groups between two separate fossiliferous layers, namely those of the stratigraphically older Bílina Delta and younger Břešťany Clay. Significant differences were confirmed in this regard, especially in connection with achieved frequency and proportional occurrences of distinct functional feeding groups in the Bílina Delta. The galls were the...
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Plants as source of isoflavonoids
Raabová, Karin ; Karlíčková, Jana (advisor) ; Vytlačilová, Jitka (referee)
CHARLES UNIVERSITY IN PRAGUE PHARMACEUTICAL FACULTY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL BOTANY AND ECOLOGY Title of the Bachelor thesis: PLANTS AS SOURCE OF ISOFLAVONOIDS Candidate: Karin Raabová Supervisor: PharmDr. Jana Karlíčková, Ph.D. Bachelor thesis 2014/2015, pp. 65 Isoflavonoids belong to the low molecular weight secondary metabolites of plants produced by many plant families, particularly plants of the family Fabaceae. They are a common part of the human diet (peas, beans, soybeans) and have many biological effects, such as the estrogenic and antioxidant effects, but also can exhibit larvicidal activity. To subsequent establish the presence of these substances in plants are most often used special instrumental (HPLC, MS, DAD) or immunological (ELISA, RIA) methods. This thesis is a literature review, which aimed to gather information about plant sources of isoflavonoids. Among their significant sources of the Kingdom Plantae belong for example Pueraria, Dalbergia, Astragalus, Belamcanda and Gynerium. Keywords: isoflavonoids, plants, biological activity, identification
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Plant microtubule-organizing centers
Škrdlová, Iveta ; Schwarzerová, Kateřina (advisor) ; Libusová, Lenka (referee)
In eukaryotic cells, microtubules are nucleated and organized by protein structures called microtubule- organizing centers. There is a great diversity in structure and morphology of these structures in eukaryotic organisms. Animal centrosome, yeast spindle pole body and basal bodies of flagellar apparatus are the best known types of so called focused microtubule-organizing centers, where microtubules are nucleated from one or two concrete sites in the cell. These focused microtubule- organizing centers are replaced by diffuse centers in higher plant cells, which means that microtubules are nucleated from dispersed nucleation sites. Focused centers are rarely found in land plant cells. These focused centers comprise bicentrioles and blepharoplasts, which give rise to the locomotory apparatus of motile spermatozoid of bryophytes, pteridophytes, cycads and Ginkgo. Another types of focused microtubule-organizing centers in bryophytes are polar organizers, and the nuclear and the plastid envelopes in mitotic and meiotic cells. Powered by TCPDF (www.tcpdf.org)
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Mechanoreception in plants
Martinek, Jan ; Vosolsobě, Stanislav (advisor) ; Kulich, Ivan (referee)
Because of their sessile nature, plants are unable to change their location and thus they are forced to adapt as much as possible to the environment they grow in. Plants evolved the ability to sense many environmental cues, which enables them to perceive the conditions in their surroundings. One class of these stimuli are mechanical forces - from wind sways to contact with obstacles, herbivores or other plants - other mechanical stimuli are e.g. gravity or sound waves. Carnivorous or climbing plants have structures specialised for perception and rapid response to mechanical stimuli. Intriguingly, there is a less spectacular but maybe even more interesting and important response to mechanical perturbation in non-specialized plants. This thesis tries to summarize ubiquity of mechanoperception in plant kingdom and its adaptive importance for the plant life - from activation of traps, to morphological adaptation for growth at windy sites, tendril coiling in climbing plants and root navigation through obstacles in soil. In the following part, the thesis summarizes the recent knowledge of molecular processes accompanied with mechanoreception, signal transduction and integration, and response to mechanostimulation. In the last part I proppose a scheme of mechanosensing workflow from initial mechanical...
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Analysis of antioxidant systems, morphological and physiological parameters in two faba bean (Vicia faba L.) cultivars during drought stress
Jelénková, Iva ; Kočová, Marie (advisor) ; Wilhelmová, Naďa (referee)
Knowledge of physiological and morfological mechanisms which are related to drought tolerance is essential in breeding high-yielding and tolerant plants, which would not suffer unfavourable environmental conditions. Drought stress can lead to oxidative damage which causes serious disorders in physiological and biochemical processes in plant cells. Antioxidants can reduce those negative effects. Morphological (dry mass of shoot and roots, height of shoot, number of leaves), physiological (photosynthetic efficiency, pigment content, relative water content-RWC) and antioxidative (catalase-CAT, ascorbate peroxidase-APX, proline) parameters were evaluated in this study using two genotypes of Vicia faba L. differing in drought susceptibility. Drought resistant (Merkur) and sensitive (Piešťanský) genotypes were exposed to 10 days of drought. Activity of CAT and APX of stressed plants rather decreased. Proline content oscillated and no evident trend or significant differences were observed in relation to drought stress. Decrease in RWC was expressed more at susceptible plants, electron-transport chain activity and pigment content were not affected much by drought. Drought susceptible genotype expressed more serious negative effects of drought in morphological parameters, however this genotype was a bit bigger than...
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The impact of human knowledge on animals and plants
Richterová, Klaudie ; Thein, Karel (advisor) ; Jirsa, Jakub (referee)
Název práce: Dopad lidského poznání na zvířata a rostliny Vedoucí práce: doc. PhDr. Karel Thein, Ph.D. Vypracovala: Klaudie Richterová Abstrakt anglicky The last century has seen the rise of interest in the welfare of animals and one of the leaders of this movement has been the philosopher Peter Singer. His theory says that animals have their own interests, just like humans, because they are able to feel pleasure and pain. On the basis of this assumption he recurs to the principle of equal consideration of interests. Nevertheless this principle applies only to animals and human beings. However, modern research proves that humans and animals are not the only sentient beings on the Earth. Plants are not simply passive things in vegetative state. According to the current research, plants are active individuals who communicate with each other, have their own system of self-defence and basically their own way of life. In accordance with this new scientific knowledge we should include plants into the application of the principle of equal consideration of interests that is if we do not want to be proponents of species superiority.
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The sampling methodology for GM plants unintentionally present in the environment
Ovesná, Jaroslava ; Kučera, Ladislav ; Sovová, Tereza ; Mitrová, Katarína ; Pouchová, Vladimíra
In this methodology, sampling of plants from agricultural crops(corn, soybean, canola and potato) is defined to assess the presence of unauthorized GM plants in the environment.The methodology is applied mainly in the field of inspection controls of the compliance with Act no.78/2004. The sampling and collected samples must represent to a maximum extent the crops of the controlled part of the field (land parcel or land parcel portion). The basic applications of the methodology include:(a) low portion of unauthorized GM plants(seed contaminated with GM plants unauthorized for cultivation), (b) monitoring of the presence of unauthorized GM plants on land parcel, where there was such an occurence recorded in previous years (for example, plants growing on the field from seeds or tubers from the so called "soil´s seed bank").
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