Structural Properties Of RNA Research Articles

Pioneering role of RNA in the early evolution of life.

The catalytic, regulatory and structural properties of RNA, combined with their extraordinary ubiquity in cellular processes, are consistent with the proposal that this molecule played a much more conspicuous role in heredity and metabolism during the early stages of biological evolution. This review explores the pivotal role of RNA in the earliest life forms and its relevance in modern biological systems. It examines current models that study the early evolution of life, providing insights into the primordial RNA world and its legacy in contemporary biology.

RNA multimerization as an organizing force for liquid-liquid phase separation.

RNA interactions are exceptionally strong and highly redundant. As such, nearly any two RNAs have the potential to interact with one another over relatively short stretches, especially at high RNA concentrations. This is especially true for pairs of RNAs that do not form strong self-structure. Such phenomena can drive liquid–liquid phase separation, either solely from RNA–RNA interactions in the presence of divalent or organic cations, or in concert with proteins. RNA interactions can drive multimerization of RNA strands via both base-pairing and tertiary interactions. In this article, we explore the tendency of RNA to form stable monomers, dimers, and higher order structures as a function of RNA length and sequence through a focus on the intrinsic thermodynamic, kinetic, and structural properties of RNA. The principles we discuss are independent of any specific type of biomolecular condensate, and thus widely applicable. We also speculate how external conditions experienced by living organisms can influence the formation of nonmembranous compartments, again focusing on the physical and structural properties of RNA. Plants, in particular, are subject to diverse abiotic stresses including extreme temperatures, drought, and salinity. These stresses and the cellular responses to them, including changes in the concentrations of small molecules such as polyamines, salts, and compatible solutes, have the potential to regulate condensate formation by melting or strengthening base-pairing. Reversible condensate formation, perhaps including regulation by circadian rhythms, could impact biological processes in plants, and other organisms.

Structural Properties of the RNA Synthesized by Glutamate Dehydrogenase for the Degradation of Total RNA

Glutamate dehydrogenase (GDH)-synthesized RNA, a nongenetic code-based RNA is suitable for unraveling the structural constraints imposed on the regulation (transcription, translation, siRNA etc.) of metabolism by genetic code. GDH-synthesized RNAs have been induced in whole plants to knock out target mRNA populations thereby producing plant phenotypes that are allergen-free; enriched in fatty acids, essential amino acids, shikimic acid, resveratrol etc. Methods applied hereunder for investigating the structural properties of GDH-synthesized RNA included purification of GDH isoenzymes, synthesis of RNA by the isoenzymes, reverse transcription of the RNA to cDNA, sequencing of the cDNA, computation of the G+C-contents, profiling the stability through PCR amplification compared with genetic code-based DNA; and biochemical characterization of the RNAs synthesized by individual hexameric isoenzymes of GDH. Single product bands resulted from the PCR amplification of the cDNAs of GDH-synthesized RNA, whereas several bands resulted from the amplification of genetic code-based DNA. The cDNAs have wide G+C-contents (35% to 59%), whereas genetic code-based DNA has narrower G+C-contents (50% to 60%). The GDH β6 homo-hexameric isoenzyme synthesized the A+U-rich RNAs, whereas the a6, and α6 homo-hexameric isoenzymes synthesized the G+C-rich RNAs. Therefore, the RNA synthesized by GDH is different from genetic code-based RNAs. In vitro chemical reactions revealed that GDH-synthesized RNA degraded total RNA to lower molecular weight products. Therefore, GDH-synthesized RNA is RNA enzyme. Dismantling of the structural constraints imposed on RNA by genetic code liberated RNA to become an enzyme with specificity to degrade unwanted transcripts. The RNA enzyme activity of GDH-synthesized RNA is ubiquitous in cells; it is readily induced by treatment of plants with mineral nutrients etc. and may simplify experimental approaches in plant enzymology and molecular biology research projects.

Reflections on the 20th anniversary of RNA.

Reflections on the 20th anniversary of RNA.