Przedmiotami wynalazku są sposób określania odporności linii kukurydzy na warunki stresu herbicyd... more Przedmiotami wynalazku są sposób określania odporności linii kukurydzy na warunki stresu herbicydowego, zestaw diagno-styczny do określania odporności linii kukurydzy na warunki stresu herbicydowego oraz zastosowanie aptamerów RNA do detekcji odpornych i/lub wrażliwych linii kukurydzy. Bardziej szczegółowo rozwiązanie dotyczy problemu doboru odpowiednich linii ho-dowlanych kukurydzy do istniejących na terenie Polski warunków geośrodowiskowych ze względu na negatywny efekt stosowania herbicydów. Pojawienie się chwastów odpornych na powszechnie używane herbicydy spowodowało stopniowe zwiększanie sto-sowanych dawek, które mogą obniżać plonowanie roślin upraw-nych (linie wrażliwe na działanie herbicydu), a jednocześnie w du-żych ilościach dostające się do wód gruntowych środki chemiczne stanowią poważne zagrożenie dla środowiska.
Incomplete oxygen reduction gives rise to reactive oxygen species (ROS). For a long time they hav... more Incomplete oxygen reduction gives rise to reactive oxygen species (ROS). For a long time they have been considered unwelcome companions of aerobic metabolism. Organisms using oxygen developed several systems of ROS scavenging with enzymatic and non enzymatic antioxidants, which allow them control the cellular level of oxygen derived from free radicals. It is well established nowadays that ROS are not necessarily negative byproducts, but they also play an important role in cellular mechanisms. They are involved in many regular cellular processes in all aerobic organisms. When the antioxidant system is overcome and the balance between ROS production and scavenging is disrupted, oxidative stress occurs. It has been reported that oxidative stress may be linked to some human diseases and is also involved in biotic and abiotic stress response in plants.
The main function of ribosome is to serve as a site of mRNA translation into a sequence of amino ... more The main function of ribosome is to serve as a site of mRNA translation into a sequence of amino acids in a process called protein biosynthesis. Most impor- tant for understanding the translational mechanism is how a ribosome interacts with the factors playing role in this complicated cellular process. The key ele- ments of these interactions are the functional domains of rRNAs. In this paper, we present the functional importance of 23S rRNA in polypeptide biosynthesis.
Structure and function of intersubunit bridges in procaryotic ribo-some S u m m a r y The main fu... more Structure and function of intersubunit bridges in procaryotic ribo-some S u m m a r y The main function of ribosome is decoding of the genetic message and for-mation of peptide bonds. Protein synthesis is a dynamic process during which tRNA and mRNA are translocated through the ribosome. Ribosomal subunits, small and large, are joined together by a series of bridges, which make possible forming of an active ribosome. It this paper we present the functional impor-tance of ribosomal bridges.
A ribosome undergoes significant conformational changes during elongation of polypeptide chain th... more A ribosome undergoes significant conformational changes during elongation of polypeptide chain that are correlated with structural changes of rRNAs. We tested nine different antisense oligodeoxynucleotides complementary to the selected, highly conserved sequences of Lupinus luteus 26S rRNA that are engaged in the interactions with tRNA molecules. The ribosomes were converted either to pre- or to posttranslocational states, with or without prehybridized oligonucleotides, using tRNA or mini-tRNA molecules. The activity of those ribosomes was tested via the so-called binding assay. We observed well-defined structural changes of ribosome's conformation during different steps of the elongation cycle of protein biosynthesis. In this article, we present that (i) before and after translocation, fragments of domain V between helices H70/H71 and H74/H89 do not have to interact with nucleotides 72-76 of the acceptor arm of A-site tRNA; (ii) helix H69 does not have to interact with DHU arm of tRNA in positions 25 and 26 after forming the peptide bond, but before translocation; (iii) helices H69 and H70 interact weakly with nucleotides 11, 12, 25, and 26 of A-site tRNA before forming a peptide bond in the ribosome; (iv) interactions between helices H80, H93 and single-stranded region between helices H92 and H93 and CCAend of P-site tRNA are necessary at all steps of elongation cycle; and (v) before and after translocation, helix H89 does not have to interact with nucleotides in positions 64-65 and 50-53 of A-site tRNA TPsiC arm.
Human ribonuclease Dicer is an enzyme that excises small regulatory RNAs from perfectly or partia... more Human ribonuclease Dicer is an enzyme that excises small regulatory RNAs from perfectly or partially double-stranded RNA precursors. Although Dicer substrates and products have already been quite well characterized, our knowledge about cellular factors regulating the activity of this enzyme is still limited. To learn more about this problem, we attempted to determine whether RNA could function not only as a Dicer substrate but also as its regulator. To this end, we applied an in vitro selection method. We identified 120 RNA oligomers binding human Dicer. Sixteen of them were subjected to more detailed in vitro studies. We found that 6 out of 16 oligomers affected Dicer ability to digest pre-microRNAs (miRNAs), although most of them were cleaved by this enzyme. For the 6 most active oligomers the putative mechanism of Dicer inhibition was determined. Three oligomers were classified as typical competitive inhibitors and one as an allosteric inhibitor. The remaining 2 oligomers acted as selective inhibitors. They affected the production of 1 miRNA, whereas the formation of other miRNAs was hardly influenced. In general, the data obtained suggest that one can modulate the generation of specific miRNAs by using RNA oligomers. Moreover, we found that sequences similar to those of the selected oligomers can be found within the molecules composing human transcriptome.
Przedmiotami wynalazku są sposób określania odporności linii kukurydzy na warunki stresu herbicyd... more Przedmiotami wynalazku są sposób określania odporności linii kukurydzy na warunki stresu herbicydowego, zestaw diagno-styczny do określania odporności linii kukurydzy na warunki stresu herbicydowego oraz zastosowanie aptamerów RNA do detekcji odpornych i/lub wrażliwych linii kukurydzy. Bardziej szczegółowo rozwiązanie dotyczy problemu doboru odpowiednich linii ho-dowlanych kukurydzy do istniejących na terenie Polski warunków geośrodowiskowych ze względu na negatywny efekt stosowania herbicydów. Pojawienie się chwastów odpornych na powszechnie używane herbicydy spowodowało stopniowe zwiększanie sto-sowanych dawek, które mogą obniżać plonowanie roślin upraw-nych (linie wrażliwe na działanie herbicydu), a jednocześnie w du-żych ilościach dostające się do wód gruntowych środki chemiczne stanowią poważne zagrożenie dla środowiska.
Incomplete oxygen reduction gives rise to reactive oxygen species (ROS). For a long time they hav... more Incomplete oxygen reduction gives rise to reactive oxygen species (ROS). For a long time they have been considered unwelcome companions of aerobic metabolism. Organisms using oxygen developed several systems of ROS scavenging with enzymatic and non enzymatic antioxidants, which allow them control the cellular level of oxygen derived from free radicals. It is well established nowadays that ROS are not necessarily negative byproducts, but they also play an important role in cellular mechanisms. They are involved in many regular cellular processes in all aerobic organisms. When the antioxidant system is overcome and the balance between ROS production and scavenging is disrupted, oxidative stress occurs. It has been reported that oxidative stress may be linked to some human diseases and is also involved in biotic and abiotic stress response in plants.
The main function of ribosome is to serve as a site of mRNA translation into a sequence of amino ... more The main function of ribosome is to serve as a site of mRNA translation into a sequence of amino acids in a process called protein biosynthesis. Most impor- tant for understanding the translational mechanism is how a ribosome interacts with the factors playing role in this complicated cellular process. The key ele- ments of these interactions are the functional domains of rRNAs. In this paper, we present the functional importance of 23S rRNA in polypeptide biosynthesis.
Structure and function of intersubunit bridges in procaryotic ribo-some S u m m a r y The main fu... more Structure and function of intersubunit bridges in procaryotic ribo-some S u m m a r y The main function of ribosome is decoding of the genetic message and for-mation of peptide bonds. Protein synthesis is a dynamic process during which tRNA and mRNA are translocated through the ribosome. Ribosomal subunits, small and large, are joined together by a series of bridges, which make possible forming of an active ribosome. It this paper we present the functional impor-tance of ribosomal bridges.
A ribosome undergoes significant conformational changes during elongation of polypeptide chain th... more A ribosome undergoes significant conformational changes during elongation of polypeptide chain that are correlated with structural changes of rRNAs. We tested nine different antisense oligodeoxynucleotides complementary to the selected, highly conserved sequences of Lupinus luteus 26S rRNA that are engaged in the interactions with tRNA molecules. The ribosomes were converted either to pre- or to posttranslocational states, with or without prehybridized oligonucleotides, using tRNA or mini-tRNA molecules. The activity of those ribosomes was tested via the so-called binding assay. We observed well-defined structural changes of ribosome's conformation during different steps of the elongation cycle of protein biosynthesis. In this article, we present that (i) before and after translocation, fragments of domain V between helices H70/H71 and H74/H89 do not have to interact with nucleotides 72-76 of the acceptor arm of A-site tRNA; (ii) helix H69 does not have to interact with DHU arm of tRNA in positions 25 and 26 after forming the peptide bond, but before translocation; (iii) helices H69 and H70 interact weakly with nucleotides 11, 12, 25, and 26 of A-site tRNA before forming a peptide bond in the ribosome; (iv) interactions between helices H80, H93 and single-stranded region between helices H92 and H93 and CCAend of P-site tRNA are necessary at all steps of elongation cycle; and (v) before and after translocation, helix H89 does not have to interact with nucleotides in positions 64-65 and 50-53 of A-site tRNA TPsiC arm.
Human ribonuclease Dicer is an enzyme that excises small regulatory RNAs from perfectly or partia... more Human ribonuclease Dicer is an enzyme that excises small regulatory RNAs from perfectly or partially double-stranded RNA precursors. Although Dicer substrates and products have already been quite well characterized, our knowledge about cellular factors regulating the activity of this enzyme is still limited. To learn more about this problem, we attempted to determine whether RNA could function not only as a Dicer substrate but also as its regulator. To this end, we applied an in vitro selection method. We identified 120 RNA oligomers binding human Dicer. Sixteen of them were subjected to more detailed in vitro studies. We found that 6 out of 16 oligomers affected Dicer ability to digest pre-microRNAs (miRNAs), although most of them were cleaved by this enzyme. For the 6 most active oligomers the putative mechanism of Dicer inhibition was determined. Three oligomers were classified as typical competitive inhibitors and one as an allosteric inhibitor. The remaining 2 oligomers acted as selective inhibitors. They affected the production of 1 miRNA, whereas the formation of other miRNAs was hardly influenced. In general, the data obtained suggest that one can modulate the generation of specific miRNAs by using RNA oligomers. Moreover, we found that sequences similar to those of the selected oligomers can be found within the molecules composing human transcriptome.
Uploads