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Ribosome Binding Site
A ribosome binding site, or ribosomal binding site (RBS), is a sequence of nucleotides upstream of the start codon of an mRNA transcript that is responsible for the recruitment of a ribosome during the initiation of translation. Mostly, RBS refers to bacterial sequences, although internal ribosome entry sites (IRES) have been described in mRNAs of eukaryotic cells or viruses that infect eukaryotes. Ribosome recruitment in eukaryotes is generally mediated by the 5' cap present on eukaryotic mRNAs. Prokaryotes The RBS in prokaryotes is a region upstream of the start codon. This region of the mRNA has the consensus 5'-AGGAGG-3', also called the Shine-Dalgarno (SD) sequence. The complementary sequence (CCUCCU), called the anti-Shine-Dalgarno (ASD) is contained in the 3’ end of the 16S region of the smaller (30S) ribosomal subunit. Upon encountering the Shine-Dalgarno sequence, the ASD of the ribosome base pairs with it, after which translation is initiated. Variations of the 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotides
Nucleotides are Organic compound, organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all Life, life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common Nutrient, nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a pentose, five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine, and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP), and uridine triph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Neural Network
In machine learning, a neural network (also artificial neural network or neural net, abbreviated ANN or NN) is a computational model inspired by the structure and functions of biological neural networks. A neural network consists of connected units or nodes called '' artificial neurons'', which loosely model the neurons in the brain. Artificial neuron models that mimic biological neurons more closely have also been recently investigated and shown to significantly improve performance. These are connected by ''edges'', which model the synapses in the brain. Each artificial neuron receives signals from connected neurons, then processes them and sends a signal to other connected neurons. The "signal" is a real number, and the output of each neuron is computed by some non-linear function of the sum of its inputs, called the '' activation function''. The strength of the signal at each connection is determined by a ''weight'', which adjusts during the learning process. Typically, ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Biosynthesis
Protein biosynthesis, or protein synthesis, is a core biological process, occurring inside Cell (biology), cells, homeostasis, balancing the loss of cellular proteins (via Proteolysis, degradation or Protein targeting, export) through the production of new proteins. Proteins perform a number of critical functions as enzymes, structural proteins or hormones. Protein synthesis is a very similar process for both prokaryotes and eukaryotes but there are some distinct differences. Protein synthesis can be divided broadly into two phases: Transcription (biology), transcription and Translation (biology), translation. During transcription, a section of DNA encoding a protein, known as a gene, is converted into a molecule called messenger RNA (mRNA). This conversion is carried out by enzymes, known as RNA polymerases, in the cell nucleus, nucleus of the cell. In eukaryotes, this mRNA is initially produced in a premature form (Primary transcript, pre-mRNA) which undergoes post-transcriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Prediction
In computational biology, gene prediction or gene finding refers to the process of identifying the regions of genomic DNA that encode genes. This includes protein-coding genes as well as RNA genes, but may also include prediction of other functional elements such as regulatory regions. Gene finding is one of the first and most important steps in understanding the genome of a species once it has been sequenced. In its earliest days, "gene finding" was based on painstaking experimentation on living cells and organisms. Statistical analysis of the rates of homologous recombination of several different genes could determine their order on a certain chromosome, and information from many such experiments could be combined to create a genetic map specifying the rough location of known genes relative to each other. Today, with comprehensive genome sequence and powerful computational resources at the disposal of the research community, gene finding has been redefined as a largely computa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeal Translation
Archaeal translation is the process by which messenger RNA is translated into proteins in archaea. Not much is known on this subject, but on the protein level it seems to resemble eukaryotic translation. Most of the initiation, elongation, and termination factors in archaea have homologs in eukaryotes. Shine-Dalgarno sequences only are found in a minority of genes for many phyla, with many leaderless mRNAs probably initiated by scanning. The process of ABCE1 ATPase-based recycling is also shared with eukaryotes. Being a prokaryote A prokaryote (; less commonly spelled procaryote) is a unicellular organism, single-celled organism whose cell (biology), cell lacks a cell nucleus, nucleus and other membrane-bound organelles. The word ''prokaryote'' comes from the Ancient Gree ... without a nucleus, archaea do perform transcription and translation at the same time like bacteria do. References Further reading * Molecular biology Protein biosynthesis Gene expression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterial Translation
Bacterial translation is the process by which messenger RNA is translated into proteins in bacteria. Initiation Initiation of translation in bacteria involves the assembly of the components of the translation system, which are: the two ribosomal subunits (50S and 30S subunits); the mature mRNA to be translated; the tRNA charged with ''N''-formylmethionine (the first amino acid in the nascent peptide); guanosine triphosphate (GTP) as a source of energy, and the three prokaryotic initiation factors IF1, IF2, and IF3, which help the assembly of the initiation complex. Variations in the mechanism can be anticipated. The ribosome has three active sites: the A site, the P site, and the E site. The ''A site'' is the point of entry for the aminoacyl tRNA (except for the first aminoacyl tRNA, which enters at the P site). The ''P site'' is where the peptidyl tRNA is formed in the ribosome. And the ''E site'' which is the exit site of the now uncharged tRNA after it gives its amino a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotic Translation
Eukaryotic translation is the biological process by which messenger RNA is Translation (biology), translated into proteins in eukaryotes. It consists of four phases: initiation, elongation, termination, and recapping. Initiation Translation initiation is the process by which the ribosome and its associated factors bind to an mRNA and are assembled at the start codon. This process is defined as either cap-dependent, in which the ribosome binds initially at the 5' cap and then travels to the stop codon, or as cap-independent, where the ribosome does not initially bind the 5' cap. Cap-dependent initiation Initiation of translation usually involves the interaction of certain key proteins, the initiation factors, with a special tag bound to the 5'-end of an mRNA molecule, the 5' cap, as well as with the 5' UTR. These proteins bind the small (40S) ribosome, ribosomal subunit and hold the mRNA in place. Eukaryotic initiation factor 3, eIF3 is associated with the 40S ribosomal subunit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Operon Ribosome Binding Site
The alpha operon ribosome binding site in bacteria is surrounded by this complex pseudoknotted RNA structure. Translation of the mRNA produces 4 ribosomal protein products, one of which (S4) acts as a translational repressor by binding to the nested pseudoknot region. The mechanism of repression is thought to involve a conformational switch in the pseudoknot region and ribosome Ribosomes () are molecular machine, macromolecular machines, found within all cell (biology), cells, that perform Translation (biology), biological protein synthesis (messenger RNA translation). Ribosomes link amino acids together in the order s ... entrapment. References External links * Cis-regulatory RNA elements {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Pittsburgh
The University of Pittsburgh (Pitt) is a Commonwealth System of Higher Education, state-related research university in Pittsburgh, Pennsylvania, United States. The university is composed of seventeen undergraduate and graduate schools and colleges at its Urban university, urban Pittsburgh campus, home to the university's central administration and around 28,000 undergraduate and graduate students. The 132-acre Pittsburgh campus includes various historic buildings that are part of the Schenley Farms Historic District, most notably its 42-story Gothic Revival architecture, Gothic revival centerpiece, the Cathedral of Learning. Pitt is a member of the Association of American Universities and is Carnegie Classification of Institutions of Higher Education, classified among "R1: Doctoral Universities – Very high research activity". Pitt traces its roots to the Pittsburgh Academy founded by Hugh Henry Brackenridge in 1787. While the city was still on the History of Pittsburgh#Gatewa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marilyn Kozak
Marilyn S. Kozak is an American professor of biochemistry at the Robert Wood Johnson Medical School. She was previously at the University of Medicine and Dentistry of New Jersey before the school was merged. She was awarded a PhD in microbiology by Johns Hopkins University studying the synthesis of the Bacteriophage MS2, advised by Daniel Nathans. Kozak sought to study the mechanism of eukaryotic translation initiation, a problem long thought to have already been solved by Joan Steitz. While in the Department of Biological Sciences at University of Pittsburgh, she published a series of studies that established the scanning model of translation initiation and the Kozak consensus sequence. Her last publication was in 2008. Recognition Kozak was listed as one of the top 10 Women Scientists of the 80's in an article published by The Scientist. This was awarded based on the number of citations for their published work between 1981-1988. During this time, Kozak had 3,107 citation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lynn Dalgarno
Lynn Dalgarno (born 12 November 1935) is an Australian geneticist known for the discovery of the Shine–Dalgarno sequence with his graduate student, John Shine. Early life and education The son of Frederick Leslie Roy Dalgarno and Nadine Ilma (née Rankin) Dalgarno, Lynn Dalgarno was born at Berklea Private Hospital, Caulfield, Victoria on 13 November 1935. Dalgarno was awarded a B.Sc.(Agr.) in 1958, conducting research with F. J. R. Hird at the Departments of Biochemistry and Agriculture, University of Melbourne, and a Ph.D. in 1962, from the Australian National University (ANU), with a dissertation titled, ''Respiratory metabolism and processes of uptake in a plant tissue'', with research advisor, L. M. Birt at The Russell Grimwade School of Biochemistry, University of Melbourne. Career In his early career (between 1963 and 1967) Dalgarno conducted research, first at the Medical Research Council's National Institute for Medical Research supported by a University of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Shine
John Shine (born 3 July 1946) is an Australian biochemist and molecular biologist. Shine and Lynn Dalgarno discovered a nucleotide sequence, called the Shine–Dalgarno sequence, necessary for the initiation of protein synthesis. He directed the Garvan Institute of Medical Research in Sydney from 1990 to 2011. From 2018 to 2022, Shine was President of the Australian Academy of Science. Background and early career The brother of scientist Richard Shine, John Shine was born in Brisbane in 1946 and completed his university studies at the Australian National University (ANU) in Canberra, graduating with a bachelor of science with honours in 1972 and completing his PhD in 1975. During the course of his studies he and his supervisor, Lynn Dalgarno, discovered the RNA sequence necessary for ribosome binding and the initiation of protein synthesis in the bacterium ''Escherichia coli''. The sequence was named the Shine–Dalgarno sequence. This was a key discovery allowing fur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
