Exploration of Antiviral Effects of RNA-dependent RNA Polymerases 3, 4 and 5 in Arabidopsis.

Small RNAs play a number of vital roles in plants, including viral resistance. A particular class of small RNA that regulates plant defense from pathogens, among other functions, is known as small interfering RNAs (siRNAs). A key player in the biogenesis pathway of siRNAs are RNA-Dependent RNA Polymerases (RDRs). There are six RDR proteins in Arabidopsis thaliana, three of which have well documented roles (RDRs 1, 2 and 6), and three of which have no documented role. Here, we look at the functions of the unstudied RDRs, RDRs 3, 4 and 5, to see whether they affect antiviral resistance

MOTOR ABILITIES OF CHILDREN IN URBAN AND RURAL AREAS

Knowledge of motor skills in young schoolchildren is directly related to the effects of physical education and the development of certain motor skills. During the younger school age, the dynamics of the development change is slower when compared to the development of preschoolers. The general mobility factor which, according to most authors, exists during the pre-school age begins to vary during the first few years of elementary school, and this is precisely the period in which children quickly develop their motor skills. The aim of this study is to determine the differences in the motor abilities of students in urban and rural areas. The sample in this study consisted of fourth-grade elementary school students (N = 120) in the municipality of Vranje. The data processing was carried out with the help of the T-test and X2 test.  What was tested was the explosive strength, speed of movement frequency, repetitive strength of the trunk and flexibility. Each test of motor ability is covered with at least three variables, and in any case, it did not happen that one group had better results in all three variables that are used for the estimation of some motor skills. Students from urban areas showed significantly better results in explosive strength of the upper limbs (MBCM) and the flexibility of the lower extremities (MDPR and MPRS). Students from rural areas showed significantly better results in speed-frequency movements of the arms and legs (MKRR and MKRN) and the repetitive strength of the trunk (MPNL and MZTL). The number of schoolchildren from urban areas who participate in sports is not significantly different from the number of schoolchildren from rural areas who are involved in sports. The difference that occurs in some variables of motor skills is most likely a consequence of specific training in the context of some field of sport, the quality of training in the field, genetics and physical activity during leisure time

Genomics of small RNAs in the Brassicales

[EMBARGOED UNTIL 6/1/2023] In Chapter 1, I examined the relationship between TEs and genome size in the Brassicales, in Chapter 2 I characterized sRNAs in Brassicaceae, and in Chapter 3 I evaluate nat-siRNAs as a sRNA type. In this introduction, I provide background on the diversity of angiosperms, with special focus on the Brassicales order, plant genomes, and small RNAs and their biogenesis.Includes bibliographical references

EU som demokratifrämjande aktör i Ukraina : En kvalitativ teorikonsumerande fallstudie om ENP:s inverkan på Ukrainas demokratiutveckling 2009-2020

Ukraine is a state that has been characterized by authoritarian trends for a long time. This is due to political division. The political regime in Ukraine has consequently been influenced by pro-Russian and pro-European actors. A minority of Ukrainan population has a desire to join Russia, while the majority of the Ukrainan population wants to join the EU. Therefore, this study will examine the influence of the European Neighborhood Policy on Ukraine’s democratic development between the period of 2009 - 2020. By using the theoretical framework of Daniel Silanders thesis “Democracy From the Outside-In? The Conceptualization and Significance of Democracy Promotion” this study has implemented the six democracy-promoting aspects - actors, interets, methods, channels, relations and impact of the ENP in Ukraine. The main result of this study shows that the European Neighborhood Policy has left a major impact in Ukraine with the different instruments that the EU has provided. For instance, the Association Agreement (AA) and the Deep and Comprehensive Free Trade Area (DCFTA). However, Russia’s involvement tends to slow down the democratization process in Ukraine, the geopolitical interests of the EU tend to consider cooperation and the lack of down-top strategies has prevented the civil society from becoming involved in the development of democracy

EU som demokratifrämjande aktör i Ukraina : En kvalitativ teorikonsumerande fallstudie om ENP:s inverkan på Ukrainas demokratiutveckling 2009-2020

Ukraine is a state that has been characterized by authoritarian trends for a long time. This is due to political division. The political regime in Ukraine has consequently been influenced by pro-Russian and pro-European actors. A minority of Ukrainan population has a desire to join Russia, while the majority of the Ukrainan population wants to join the EU. Therefore, this study will examine the influence of the European Neighborhood Policy on Ukraine’s democratic development between the period of 2009 - 2020. By using the theoretical framework of Daniel Silanders thesis “Democracy From the Outside-In? The Conceptualization and Significance of Democracy Promotion” this study has implemented the six democracy-promoting aspects - actors, interets, methods, channels, relations and impact of the ENP in Ukraine. The main result of this study shows that the European Neighborhood Policy has left a major impact in Ukraine with the different instruments that the EU has provided. For instance, the Association Agreement (AA) and the Deep and Comprehensive Free Trade Area (DCFTA). However, Russia’s involvement tends to slow down the democratization process in Ukraine, the geopolitical interests of the EU tend to consider cooperation and the lack of down-top strategies has prevented the civil society from becoming involved in the development of democracy

Further insight into the bioactivity of the freshwater sponge Ochridaspongia rotunda

Context: Bioprospection has become a dynamic scientific field that explores novel possibilities for the implementation of natural products in medicine and pharmacy. Compared to marine species from all kingdoms, freshwater species have been highly neglected. Objective: This work focuses on the screening of acetylcholinesterase inhibitory (AChE) and mutagenic activities of the acetone extract (obtained by maceration) of the freshwater sponge Ochridaspongia rotunda Arndt (Malawispongiidae) in vitro. Materials and methods: AChE inhibitory activity was evaluated both in liquid (five different concentrations of the extract, from 1 to 100 μg/mL) and in solid (seven different concentrations of the extract, from 0.5 to 10.0 μg) by methods well described in literature, while mutagenicity was estimated using the Ames test (four different concentrations of the extract, from 0.106 to 1.328 mg/plate). Results: Ochridaspongia rotunda acetone extract exhibited promising AChE inhibitory activity in a dose-dependent manner both in liquid (IC50 23.07 μg/mL) and in solid (1.50 μg). Furthermore, the Ames test revealed no sign of mutagenicity at any concentration tested. Its FTIR spectrum coupled with the positive Liebermann?Burchard, Salkowski and Zak color reactions (tests) indicated the presence of sterol compounds. Discussion and conclusion: The screened extract may inspire a search for novel anticholinesterase therapeutic agent(s) potentially used in the treatment of Alzheimer's disease. Further research will be directed toward its detailed chemical analysis along with addressing the issue of a real producer of the natural product(s) responsible for the AChE activity observed

A contribution to pharmaceutical biology of freshwater sponges

<p><i>In vitro</i> anti-tumour and anti-radical activities of the acetone extract of the freshwater sponge <i>Ochridaspongia rotunda</i> were the subject of this study. The extract was found to be highly cytotoxic to human lung tumour cell line A-549 reaching IC₅₀ value of 5.01 ± 0.21 μg/mL. Indeed, it displayed only 2-fold less anti-tumour activity than doxorubicin (IC₅₀ value 2.42 ± 0.13 μg/mL) used as a positive control. The same extract was also found to be almost 37-fold more selective against A-549 vs. MRC-5 (normal) lung cells, in difference to weak selectivity of doxorubicin (less than 3-fold). Its profound anti-DPPH radical activity comparable to that of quercetin (IC₅₀ values 3.68 ± 0.19 and 3.14 ± 0.09 μg/mL, respectively) coupled with no signs of genotoxicity in the comet assay (MRC-5 cell line, vs. doxorubicin) has actually implicated the importance of this animal bioresource in searching for pharmaceutically useful bioactive compounds of natural origin.</p

Comparative phylogenetics of repetitive elements in a diverse order of flowering plants (Brassicales).

Genome sizes of plants have long piqued the interest of researchers due to the vast differences among organisms. However, the mechanisms that drive size differences have yet to be fully understood. Two important contributing factors to genome size are expansions of repetitive elements, such as transposable elements (TEs), and whole-genome duplications (WGD). Although studies have found correlations between genome size and both TE abundance and polyploidy, these studies typically test for these patterns within a genus or species. The plant order Brassicales provides an excellent system to further test if genome size evolution patterns are consistent across larger time scales, as there are numerous WGDs. This order is also home to one of the smallest plant genomes, Arabidopsis thaliana-chosen as the model plant system for this reason-as well as to species with very large genomes. With new methods that allow for TE characterization from low-coverage genome shotgun data and 71 taxa across the Brassicales, we confirm the correlation between genome size and TE content, however, we are unable to reconstruct phylogenetic relationships and do not detect any shift in TE abundance associated with WGD

Premeiotic 24-nt phasiRNAs are present in the Zea genus and unique in biogenesis mechanism and molecular function.

Reproductive phasiRNAs (phased, small interfering RNAs) are broadly present in angiosperms and play crucial roles in sustaining male fertility. While the premeiotic 21-nt (nucleotides) phasiRNAs and meiotic 24-nt phasiRNA pathways have been extensively studied in maize (Zea mays) and rice (Oryza sativa), a third putative category of reproductive phasiRNAs-named premeiotic 24-nt phasiRNAs-have recently been reported in barley (Hordeum vulgare) and wheat (Triticum aestivum). To determine whether premeiotic 24-nt phasiRNAs are also present in maize and related species and begin to characterize their biogenesis and function, we performed a comparative transcriptome and degradome analysis of premeiotic and meiotic anthers from five maize inbred lines and three teosinte species/subspecies. Our data indicate that a substantial subset of the 24-nt phasiRNA loci in maize and teosinte are already highly expressed at the premeiotic phase. The premeiotic 24-nt phasiRNAs are similar to meiotic 24-nt phasiRNAs in genomic origin and dependence on DCL5 (Dicer-like 5) for biogenesis, however, premeiotic 24-nt phasiRNAs are unique in that they are likely i) not triggered by microRNAs, ii) not loaded by AGO18 proteins, and iii) not capable of mediating PHAS precursor cleavage. In addition, we also observed a group of premeiotic 24-nt phasiRNAs in rice using previously published data. Together, our results indicate that the premeiotic 24-nt phasiRNAs constitute a unique class of reproductive phasiRNAs and are present more broadly in the grass family (Poaceae) than previously known