Instruct: Given a question, retrieve documents that can help answer the question.
Query: When was the theory of RNA announced?
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.
In cells, DNA is housed in the nucleus and it never leaves. The DNA within the nucleus is transcribed by tRNA, and the transcriptions of the DNA become RNA. The RNA (ribonucleic acid) leaves the nucleus to float freely around the cytoplasm, and it contains the instructions of the DNA that are vital to the coding, decoding, regulation and expression of genes. The ribosomes then take the RNA messages and turn them into proteins that build cells. When a virus enters a cell and inserts its DNA code into the nucleus, it gets transcribed and released into the cell for the ribosome to make it into a protein. This is how viral infections occur. The cell then explodes with the overproduction of the virus, releasing it into the body to infect any and all other cells it finds. It is theorized that through evolution, cells developed a defense system called RNAi (RNA interference) to stop the production of the proteins that have suspicious mirror image messages of the RNA. They don’t just destroy the suspicious messages, but the correct messages as well to stop all production of that message. This is a cell’s self-destruct mechanism and every cell, plant and animal, have RNAi: a way to turn off the production of a certain gene inside the protein.
Various genetic discoveries have been essential in the development of genetic engineering. Genetic inheritance was first discovered by Gregor Mendel in 1865 following experiments crossing peas. Although largely ignored for 34 years he provided the first evidence of hereditary segregation and independent assortment. In 1889 Hugo de Vries came up with the name "(pan)gene" after postulating that particles are responsible for inheritance of characteristics and the term "genetics" was coined by William Bateson in 1905. In 1928 Frederick Griffith proved the existence of a "transforming principle" involved in inheritance, which Avery, MacLeod and McCarty later (1944) identified as DNA. Edward Lawrie Tatum and George Wells Beadle developed the central dogma that genes code for proteins in 1941. The double helix structure of DNA was identified by James Watson and Francis Crick in 1953.As well as discovering how DNA works, tools had to be developed that allowed it to be manipulated. In 1970 Hamilton Smith's lab discovered restriction enzymes that allowed DNA to be cut at specific places and separated out on an electrophoresis gel. This enabled scientists to isolate genes from an organism's genome. DNA ligases, that join broken DNA together, had been discovered earlier in 1967 and by combining the two enzymes it was possible to "cut and paste" DNA sequences to create recombinant DNA. Plasmids, discovered in 1952, became important tools for transferring information between cells and replicating DNA sequences. Frederick Sanger developed a method for sequencing DNA in 1977, greatly increasing the genetic information available to researchers. Polymerase chain reaction (PCR), developed by Kary Mullis in 1983, allowed small sections of DNA to be amplified and aided identification and isolation of genetic material.
The second half of the 20th century was the golden age of virus discovery and most of the over 2,000 recognised species of animal, plant, and bacterial viruses were discovered during these years. In 1957, equine arterivirus and the cause of Bovine virus diarrhoea (a pestivirus) were discovered. In 1963, the hepatitis B virus was discovered by Baruch Blumberg, and in 1965, Howard Temin described the first retrovirus. Reverse transcriptase, the enzyme that retroviruses use to make DNA copies of their RNA, was first described in 1970, independently by Howard Martin Temin and David Baltimore. In 1983 Luc Montagnier's team at the Pasteur Institute in France, first isolated the retrovirus now called HIV. In 1989 Michael Houghton's team at Chiron Corporation discovered Hepatitis C.
On 10 June 1948, Tamm headed a new group of theorists which included Andrei Sakharov, Vitaly Ginzburg, S.Z. Belenky and Romanov. They followed up Sakharov's ideas for a new thermonuclear weapon and went to KB-11 (now the All-Russian Scientific Research Institute of Experimental Physics) in the closed city of Sarov, Nizhny Novgorod. He started as a junior researcher, then senior, then head of department. In 1952, he received a degree in Physical and Mathematical Sciences with a thesis on kinetic processes of neutrons. This work on neutrons and efficiency continued, along with calculations on nuclear reaction kinetics and energy release of the Soviet Union's first thermonuclear weapon, the RDS-6, tested in 1953; for this he was awarded the Stalin Prize, the first of several awards. He was a leading developer of the RDS-37 - the first Soviet two-stage thermonuclear weapon - most specifically concerned with the power output. Romanov transferred to the new Scientific Research Institute-1011 as head of the theoretical department in 1955. Two years later, his team had developed a new megatonne-yield bomb design. He gained a Ph.D. in Physical and Mathematical Sciences in 1958 and was appointed to professorship of theoretical physics in 1962.
Only one of the two DNA strands serve as a template for transcription. The antisense strand of DNA is read by RNA polymerase from the 3' end to the 5' end during transcription (3' → 5'). The complementary RNA is created in the opposite direction, in the 5' → 3' direction, matching the sequence of the sense strand with the exception of switching uracil for thymine. This directionality is because RNA polymerase can only add nucleotides to the 3' end of the growing mRNA chain. This use of only the 3' → 5' DNA strand eliminates the need for the Okazaki fragments that are seen in DNA replication. This also removes the need for an RNA primer to initiate RNA synthesis, as is the case in DNA replication.
In 1967, it was discovered that mitochondria contained ribosomes. In 1968, methods were developed for mapping the mitochondrial genes, with the genetic and physical map of yeast mitochondrial DNA being completed in 1976.
The northern blot is used to study the expression patterns of a specific type of RNA molecule as relative comparison among a set of different samples of RNA. It is essentially a combination of denaturing RNA gel electrophoresis, and a blot. In this process RNA is separated based on size and is then transferred to a membrane that is then probed with a labeled complement of a sequence of interest. The results may be visualized through a variety of ways depending on the label used; however, most result in the revelation of bands representing the sizes of the RNA detected in sample. The intensity of these bands is related to the amount of the target RNA in the samples analyzed. The procedure is commonly used to study when and how much gene expression is occurring by measuring how much of that RNA is present in different samples. It is one of the most basic tools for determining at what time, and under what conditions, certain genes are expressed in living tissues.
One strand of the DNA, the "template strand" (or noncoding strand), is used as a template for RNA synthesis. As transcription proceeds, RNA polymerase traverses the template strand and uses base pairing complementarity with the DNA template to create an RNA copy (which elongates during the traversal). Although RNA polymerase traverses the template strand from 3' → 5', the coding (non-template) strand and newly formed RNA can also be used as reference points, so transcription can be described as occurring 5' → 3'. This produces an RNA molecule from 5' → 3', an exact copy of the coding strand (except that thymines are replaced with uracils, and the nucleotides are composed of a ribose (5-carbon) sugar where DNA has deoxyribose (one fewer oxygen atom) in its sugar-phosphate backbone).
Mitochondrial DNA was discovered in the 1960s by Margit M. K. Nass and Sylvan Nass by electron microscopy as DNase-sensitive threads inside mitochondria, and by Ellen Haslbrunner, Hans Tuppy and Gottfried Schatz by biochemical assays on highly purified mitochondrial fractions.
The Human Genome Project (HGP) was an international scientific research project with the goal of determining the sequence of nucleotide base pairs that make up human DNA, and of identifying and mapping all of the genes of the human genome from both a physical and a functional standpoint. It remains the world's largest collaborative biological project. After the idea was picked up in 1984 by the US government when the planning started, the project formally launched in 1990 and was declared complete on April 14, 2003. Funding came from the US government through the National Institutes of Health (NIH) as well as numerous other groups from around the world. A parallel project was conducted outside government by the Celera Corporation, or Celera Genomics, which was formally launched in 1998. Most of the government-sponsored sequencing was performed in twenty universities and research centers in the United States, the United Kingdom, Japan, France, Germany and China.
DNA, RNA and proteins are most common sequence-controlled polymers in living creatures. Inspired by them, polymerization methods, utilizing DNA or RNA as templates to control sequences of polymer, are developed. At first, taking DNA or RNA as templates, scientists developed a series of peptide nucleic acid (PNA)-based polymers, without using DNA polymerases. But this method is limited to polymerization scale and yield. After that, polymerase chain reaction (PCR) is developed, which currently is still the most extensively used sequence-regulated method. By employing enzymes, the yields and scales are greatly increased, but the specificity of enzymes towards natural peptides limits this technique to a certain degree. Nowadays, more attention is paid to utilization of ribosomes to directly mimic the transcription and translation process. This technology called protein engineering is considered as the most promising biological polymerization method for synthesis of sequence-controlled polymers.
The Human Genome Project (HGP) was declared complete in April 2003. An initial rough draft of the human genome was available in June 2000 and by February 2001 a working draft had been completed and published followed by the final sequencing mapping of the human genome on April 14, 2003. Although this was reported to cover 99% of the euchromatic human genome with 99.99% accuracy, a major quality assessment of the human genome sequence was published on May 27, 2004 indicating over 92% of sampling exceeded 99.99% accuracy which was within the intended goal. Further analyses and papers on the HGP continue to occur.
In 1961, Jacques Monod, Jean-Pierre Changeux and François Jacob discovered the lac operon in the bacterium "Escherichia coli". It was a cluster of genes, arranged in a feedback control loop so that its products would only be made when "switched on" by an environmental stimulus. One of these products was an enzyme that splits a sugar, lactose; and lactose itself was the stimulus that switched the genes on. This was a revelation, as it showed for the first time that genes, even in an organism as small as a bacterium, were subject to fine-grained control. The implication was that many other genes were also elaborately regulated.
In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all organisms and also the basic unit of reproduction. With continual improvements made to microscopes over time, magnification technology advanced enough to discover cells in the 17th century. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, also known as cell biology. Over a century later, many debates about cells began amongst scientists. Most of these debates involved the nature of cellular regeneration, and the idea of cells as a fundamental unit of life. Cell theory was eventually formulated in 1839. This is usually credited to Matthias Schleiden and Theodor Schwann. However, many other scientists like Rudolf Virchow contributed to the theory. It was an important step in the movement away from spontaneous generation.
In 1989, one of the first Human Genome Project grants went to Waterston and Sulston to begin the sequencing of the worm genome. They were so successful that at the same time that the Wellcome Trust established the Sanger Centre with Sulston at its head, Waterston received funding from the National Human Genome Research Institute to undertake large-scale human sequencing at his Washington University lab. The partnership became the first to complete the sequence of a multicellular organism when the worm genome was published in December 1998, and both labs played key roles in the sequencing of the human genome, with Waterston’s lab contributing more of the finished sequence than any other US lab. The partnership went on have leading roles in the sequencing of both the mouse and chimpanzee genomes.
The HIV genome presented several additional mysteries. The virus genome contained regions that might specify as yet unknown proteins. The Haseltine laboratory discovered a novel transacting protein and a second protein, both required for virus replication. They named the transactivator tat and the second protein art; the latter was renamed rev. He predicted that drugs that target these proteins will also be effective in treating the infection. A drug that inhibits the "rev" protein has been approved by the USA Food and Drug administration for treatment of HIV infection. His laboratory went on to discover additional viral genes and proteins – "vpr", "vpu", "vif", and "nef" - required for efficient virus growth in some but not all circumstances. The discoveries were summarized in an article in 1988 in "Scientific American".
Another group working contemporaneously with the Montagnier and Gallo groups was that of Dr. Jay Levy at the University of California, San Francisco. He independently discovered the AIDS virus in 1983 and named it the AIDS associated retrovirus (ARV). This virus was very different from the virus reported by the Montagnier and Gallo groups. The ARV strains indicated, for the first time, the heterogeneity of HIV isolates and several of these remain classic examples of the AIDS virus found in the United States.
First proposed by Luigi Fantappiè in 1954, the theory remained obscure until it was rediscovered in 1968 by Henri Bacry and Jean-Marc Lévy-Leblond. In 1972, Freeman Dyson popularized it as a hypothetical road by which mathematicians could have guessed part of the structure of general relativity before it was discovered. The discovery of the accelerating expansion of the universe has led to a revival of interest in de Sitter invariant theories, in conjunction with other speculative proposals for new physics, like doubly special relativity.
It was not until French President François Mitterrand and American President Ronald Reagan met in person that the major issues were ironed out. The scientific protagonists finally agreed to share credit for the discovery of HIV, and in 1986, both the French and the US names (LAV and HTLV-III) were dropped in favor of the new term "human immunodeficiency virus" (virus de l'immunodéficience humaine, abbreviated HIV or VIH) (Coffin, 1986). They concluded that the origin of the HIV-1 Lai/IIIB isolate discovered by Gallo was the same as that discovered by Montagnier (but not known by Montagnier to cause AIDS). This compromise allowed Montagnier and Gallo to end their feud and collaborate with each other again, writing a chronology that appeared in "Nature" that year.
Cell theory led biologists to re-envision individual organisms as interdependent assemblages of individual cells. Scientists in the rising field of cytology, armed with increasingly powerful microscopes and new staining methods, soon found that even single cells were far more complex than the homogeneous fluid-filled chambers described by earlier microscopists. Robert Brown had described the nucleus in 1831, and by the end of the 19th century cytologists identified many of the key cell components: chromosomes, centrosomes mitochondria, chloroplasts, and other structures made visible through staining. Between 1874 and 1884 Walther Flemming described the discrete stages of mitosis, showing that they were not artifacts of staining but occurred in living cells, and moreover, that chromosomes doubled in number just before the cell divided and a daughter cell was produced. Much of the research on cell reproduction came together in August Weismann's theory of heredity: he identified the nucleus (in particular chromosomes) as the hereditary material, proposed the distinction between somatic cells and germ cells (arguing that chromosome number must be halved for germ cells, a precursor to the concept of meiosis), and adopted Hugo de Vries's theory of pangenes. Weismannism was extremely influential, especially in the new field of experimental embryology.
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.
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.
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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.