When was the theory of RNA announced?
611104#8
In August 1961, at the International Congress of Biochemistry in Moscow, Nirenberg presented his paper. The experimentation with synthetic RNA in a cell-free system was a key technical innovation. In 1961, when they announced their methods for decoding the relationship of mRNA to amino acids, there was still a lot of experimentation required before the entire code was deciphered. The scientists had to determine which bases made up each codon, then determine the sequence of bases in the codons. This proved to be a tremendous amount of work.
Nirenberg and Matthaei experiment
25758#22
At first, regulatory RNA was thought to be a eukaryotic phenomenon, a part of the explanation for why so much more transcription in higher organisms was seen than had been predicted. But as soon as researchers began to look for possible RNA regulators in bacteria, they turned up there as well. Currently, the ubiquitous nature of systems of RNA regulation of genes has been discussed as support for the RNA World theory. Bacterial small RNAs generally act via antisense pairing with mRNA to down-regulate its translation, either by affecting stability or affecting cis-binding ability. Riboswitches have also been discovered. They are cis-acting regulatory RNA sequences acting allosterically. They change shape when they bind metabolites so that they gain or lose the ability to bind chromatin to regulate expression of genes.
RNA
1058599#43
In 1967, Piaget considered the possibility of RNA molecules as likely embodiments of his still-abstract schemas (which he promoted as units of action)—though he did not come to any firm conclusion. At that time, due to work such as that of Swedish biochemist Holger Hydén, RNA concentrations had, indeed, been shown to correlate with learning, so the idea was quite plausible.
Piaget's theory of cognitive development
1058599#44
However, by the time of Piaget's death in 1980, this notion had lost favor. One main problem was over the protein which, it was assumed, such RNA would necessarily produce, and that did not fit in with observation. It was determined that only about 3% of RNA does code for protein. Hence, most of the remaining 97% (the "ncRNA") could theoretically be available to serve as Piagetian schemas (or other regulatory roles in the 2000s under investigation). The issue has not yet been resolved experimentally, but its theoretical aspects were reviewed in 2008 — then developed further from the viewpoints of biophysics and epistemology. Meanwhile, this RNA-based approach also unexpectedly offered explanations for other several biological issues unresolved, thus providing some measure of corroboration.
Piaget's theory of cognitive development
29491519#31
At the time of the hypercycle theory formulation, ribozymes were not known. After the breakthrough of discovering RNA's catalytic properties in 1982, it was realized that RNA had the ability to integrate protein and nucleotide-chain properties into one entity. Ribozymes potentially serving as templates and catalysers of replication can be considered components of quasispecies that can self-organize into a hypercycle without the need to invent a translation process. In 2001, a partial RNA polymerase ribozyme was designed via directed evolution. Nevertheless, it was able to catalyse only a polymerization of a chain having the size of about 14 nucleotides, even though it was 200 nucleotides long. The most up-to-date version of this polymerase was shown in 2013. While it has an ability to catalyse polymerization of longer sequences, even of its own length, it cannot replicate itself due to a lack of sequence generality and its inability to transverse secondary structures of long RNA templates. However, it was recently shown that those limitations could in principle be overcome by the assembly of active polymerase ribozymes from several short RNA strands. In 2014, a cross-chiral RNA polymerase ribozyme was demonstrated. It was hypothesized that it offers a new mode of recognition between an enzyme and substrates, which is based on the shape of the substrate, and allows avoiding the Watson-Crick pairing and, therefore, may provide greater sequence generality. Various other experiments have shown that, besides bearing polymerase properties, ribozymes could have developed other kinds of evolutionarily useful catalytic activity such as synthase, ligase, or aminoacylase activities. Ribozymal aminoacylators and ribozymes with the ability to form peptide bonds might have been crucial to inventing translation. An RNA ligase, in turn, could link various components of quasispecies into one chain, beginning the process of a genome integration. An RNA with a synthase or a synthetase activity could be critical for building compartments and providing building blocks for growing RNA and protein chains as well as other types of molecules. Many examples of this kind of ribozyme are currently known, including a peptidyl transferase ribozyme, a ligase, and a nucleotide synthetase. A transaminoacylator described in 2013 has five nucleotides, which is sufficient for a trans-amino acylation reaction and makes it the smallest ribozyme that has been discovered. It supports a peptidyl-RNA synthesis that could be a precursor for the contemporary process of linking amino acids to tRNA molecules. An RNA ligase's catalytic domain, consisting of 93 nucleotides, proved to be sufficient to catalyse a linking reaction between two RNA chains. Similarly, an acyltransferase ribozyme 82 nucleotides long was sufficient to perform an acyltransfer reaction. Altogether, the results concerning the RNA ligase's catalytic domain and the acyltransferase ribozyme are in agreement with the estimated upper limit of 100 nucleotides set by the error threshold problem. However, it was hypothesized that even if the putative first RNA-dependent RNA-polymerases are estimated to be longer—the smallest reported up-to-date RNA-dependent polymerase ribozyme is 165 nucleotides long—they did not have to arise in one step. It is more plausible that ligation of smaller RNA chains performed by the first RNA ligases resulted in a longer chain with the desired catalytically active polymerase domain.
Hypercycle (chemistry)
472878#86
On June 4, 2010, the university unveiled a new $12.5 million biomedical research center, The RNA Institute, whose mission would be to form an alliance of genetic scientists and biomedical investigators from New York's Capital Region to spur research and development into RNA and its implications for medicines, drug therapies and technologies, and curing disease. On Nov. 5, 2010, UAlbany announced The RNA Institute had received a $5.37 million grant from the National Institutes of Health/National Center for Research Resources (NIH/NCRR) and $2 million in matching funds from the State of New York to fund the design, engineering and construction of of research facilities on par with those of modern pharmaceutical companies. Comple On the same day, the institute announced the establishment of The RNA Institute MassSpec Center, dedicated to the development of mass spectrometry-based technologies for investigating the structure-function relationships of natural and synthetic RNA as tools for drug discovery.
University at Albany, SUNY
258695#3
Ŭ represents a semivowel in the orthography of Esperanto, which is an international auxiliary language publicly presented in 1887. As in Belarusian, Esperanto Ŭ is pronounced as a non-syllabic , primarily in the diphthongs "aŭ", "eŭ" and rarely "oŭ".
Ŭ
14046416#2
This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with 2-oxoglutarate as one donor, and incorporation of one atom o oxygen into each donor. The systematic name of this enzyme class is N6,N6,N6-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating). Other names in common use include trimethyllysine alpha-ketoglutarate dioxygenase, TML-alpha-ketoglutarate dioxygenase, TML hydroxylase, 6-N,6-N,6-N-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase, and (3-hydroxylating). This enzyme participates in lysine degradation and L-carnitine biosynthesis and requires the presence of iron and ascorbate.
Trimethyllysine dioxygenase
59575257#39
As noted above, Colin Blake, the author of the Gilbert-Blake theory for the origin of introns and exons, states, “Recent work by Senapathy, when applied to RNA, comprehensively explains the origin of the segregated form of RNA into coding and noncoding regions. It also suggests why a splicing mechanism was developed at the start of primordial evolution.”
Split gene theory
7892999#1
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Ȼ