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Karissa Sanbonmatsu
Karissa Y. Sanbonmatsu is an American structural biologist at Los Alamos National Laboratory. She works on the mechanism of non-coding RNA complexes including the ribosome, riboswitches, long non-coding RNAs, as well as chromatin. She was the first to perform an atomistic simulation of the ribosome, determine the secondary structure of an intact lncRNA and to publish one billion atom simulationof a biomolecular complex. Education and early career Sanbonmatsu was born in Rochester, New York, the daughter of Joan Loveridge-Sanbonmatsu, and Akira Loveridge-Sanbonmatsu, who are both professors of speech communication in the State University of New York. She attended Oswego High School, and was valedictorian. She won the Pembroke College Stokes Society Scientific Lecture Competition at the University of Cambridge. Sanbonmatsu studied physics at Columbia University, where she used the Very Large Array radio telescope to estimate the distance to supernova remnant G27.4+0.0 and its c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhattan, Columbia is the oldest institution of higher education in New York and the fifth-oldest institution of higher learning in the United States. It is one of nine colonial colleges founded prior to the Declaration of Independence. It is a member of the Ivy League. Columbia is ranked among the top universities in the world. Columbia was established by royal charter under George II of Great Britain. It was renamed Columbia College in 1784 following the American Revolution, and in 1787 was placed under a private board of trustees headed by former students Alexander Hamilton and John Jay. In 1896, the campus was moved to its current location in Morningside Heights and renamed Columbia University. Columbia scientists and scholars have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Very Large Array
The Karl G. Jansky Very Large Array (VLA) is a centimeter-wavelength radio astronomy observatory located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~ west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes (twenty-seven of which are operational while one is always rotating through maintenance) deployed in a Y-shaped array and all the equipment, instrumentation, and computing power to function as an interferometer. Each of the massive telescopes is mounted on double parallel railroad tracks, so the radius and density of the array can be transformed to adjust the balance between its angular resolution and its surface brightness sensitivity. Astronomers using the VLA have made key observations of black holes and protoplanetary disks around young stars, discovered magnetic filaments and traced complex gas motions at the Milky Way's center, probed the Universe's cosmological parameters, and provided new knowled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Repressor
In molecular genetics, a repressor is a DNA- or RNA-binding protein that inhibits the expression of one or more genes by binding to the operator or associated silencers. A DNA-binding repressor blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. An RNA-binding repressor binds to the mRNA and prevents translation of the mRNA into protein. This blocking or reducing of expression is called repression. Function If an inducer, a molecule that initiates the gene expression, is present, then it can interact with the repressor protein and detach it from the operator. RNA polymerase then can transcribe the message (expressing the gene). A co-repressor is a molecule that can bind to the repressor and make it bind to the operator tightly, which decreases transcription. A repressor that binds with a co-repressor is termed an ''aporepressor'' or ''inactive repressor''. One type of aporepressor is the trp repressor, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiotensin-converting Enzyme 2
Angiotensin-converting enzyme 2 (ACE2) is an enzyme that can be found either attached to the membrane of cells (mACE2) in the intestines, kidney, testis, gallbladder, and heart or in a soluble form (sACE2). Both membrane bound and soluble ACE2 are integral parts of the renin–angiotensin–aldosterone system (RAAS) that exists to keep the body's blood pressure in check. While mACE2 does not appear to factor into the harmful phase of RAAS (the increase of blood pressure), its existence is vital in order for the enzyme ADAM17 to cleave its extracellular domain to create soluble ACE2 (sACE2). Soluble ACE2 lowers blood pressure by catalyzing the hydrolysis of angiotensin II (a vasoconstrictor peptide) into angiotensin (1–7) (a vasodilator) which in turns binds to MasR receptors creating localized vasodilation and hence decreasing blood pressure. This decrease in blood pressure makes the entire process a promising drug target for treating cardiovascular diseases. mACE2 also ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronavirus Spike Protein
Spike (S) glycoprotein (sometimes also called spike protein, formerly known as E2) is the largest of the four major structural proteins found in coronaviruses. The spike protein assembles into trimers that form large structures, called spikes or peplomers, that project from the surface of the virion. The distinctive appearance of these spikes when visualized using negative stain transmission electron microscopy, "recalling the solar corona", gives the virus family its name. The function of the spike glycoprotein is to mediate viral entry into the host cell by first interacting with molecules on the exterior cell surface and then fusing the viral and cellular membranes. Spike glycoprotein is a class I fusion protein that contains two regions, known as S1 and S2, responsible for these two functions. The S1 region contains the receptor-binding domain that binds to receptors on the cell surface. Coronaviruses use a very diverse range of receptors; SARS-CoV (which causes SARS) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryo-Electron Microscopy
Cryogenic electron microscopy (cryo-EM) is a cryomicroscopy technique applied on samples cooled to cryogenic temperatures. For biological specimens, the structure is preserved by embedding in an environment of vitreous ice. An aqueous sample solution is applied to a grid-mesh and plunge-frozen in liquid ethane or a mixture of liquid ethane and propane. While development of the technique began in the 1970s, recent advances in detector technology and software algorithms have allowed for the determination of biomolecular structures at near-atomic resolution. This has attracted wide attention to the approach as an alternative to X-ray crystallography or NMR spectroscopy for macromolecular structure determination without the need for crystallization. In 2017, the Nobel Prize in Chemistry was awarded to Jacques Dubochet, Joachim Frank, and Richard Henderson "for developing cryo-electron microscopy for the high-resolution structure determination of biomolecules in solution." ''Nature M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Contact
In protein folding, a native contact is a contact between the side chains of two amino acids that are not neighboring in the amino acid sequence (i.e., they are more than four residues apart in the primary sequence in order to remove trivial i to i+4 contacts along alpha helices) but are spatially close in the protein's native state tertiary structure. The fraction of native contacts reproduced in a particular structure is often used as a reaction coordinate for measuring the deviation from the native state of structures produced during molecular dynamics simulations or in benchmarks of protein structure prediction methods. The contact order is a measure of the locality of a protein's native contacts; that is, the sequence distance between amino acids that form contacts. Proteins with low contact order are thought to fold faster and some may be candidates for downhill folding Downhill folding is a process in which a protein folds without encountering any significant macroscopic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epigenetics
In biology, epigenetics is the study of stable phenotypic changes (known as ''marks'') that do not involve alterations in the DNA sequence. The Greek prefix '' epi-'' ( "over, outside of, around") in ''epigenetics'' implies features that are "on top of" or "in addition to" the traditional genetic basis for inheritance. Epigenetics most often involves changes that affect the regulation of gene expression, but the term can also be used to describe any heritable phenotypic change. Such effects on cellular and physiological phenotypic traits may result from external or environmental factors, or be part of normal development. The term also refers to the mechanism of changes: functionally relevant alterations to the genome that do not involve mutation of the nucleotide sequence. Examples of mechanisms that produce such changes are DNA methylation and histone modification, each of which alters how genes are expressed without altering the underlying DNA sequence. Gene expression c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Non-coding RNA
Long non-coding RNAs (long ncRNAs, lncRNA) are a type of RNA, generally defined as transcripts more than 200 nucleotides that are not translated into protein. This arbitrary limit distinguishes long ncRNAs from small non-coding RNAs, such as microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long intervening/intergenic noncoding RNAs (lincRNAs) are sequences of lncRNA which do not overlap protein-coding genes. Long non-coding RNAs include intergenic lincRNAs, intronic ncRNAs, and sense and antisense lncRNAs, each type showing different genomic positions in relation to genes and exons. Abundance In 2007 a study found only one-fifth of transcription across the human genome is associated with protein-coding genes, indicating at least four times more long non-coding than coding RNA sequences. Large-scale complementary DNA (cDNA) sequencing projects such as FANTOM reveal the complexity of this t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercomputer
A supercomputer is a computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second ( FLOPS) instead of million instructions per second (MIPS). Since 2017, there have existed supercomputers which can perform over 1017 FLOPS (a hundred quadrillion FLOPS, 100 petaFLOPS or 100 PFLOPS). For comparison, a desktop computer has performance in the range of hundreds of gigaFLOPS (1011) to tens of teraFLOPS (1013). Since November 2017, all of the world's fastest 500 supercomputers run on Linux-based operating systems. Additional research is being conducted in the United States, the European Union, Taiwan, Japan, and China to build faster, more powerful and technologically superior exascale supercomputers. Supercomputers play an important role in the field of computational science, and are used for a wide range of computationally intensive tasks in var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Q-machine
A Q-machine is a device that is used in experimental plasma physics. The name Q-machine stems from the original intention of creating a quiescent plasma that is free from the fluctuations that are present in plasmas created in electric discharges. The Q-machine was first described in a publication by Rynn and D'Angelo. The Q-machine plasma is created at a plate that has been heated to about 2000 K and hence is called the hot plate. Electrons are emitted by the hot plate through thermionic emission, and ions are created through contact ionization of atoms of alkali metals that have low ionisation potentials. The hot plate is made of a metal that has a large work function and can withstand high temperatures, e.g. tungsten or rhenium. The alkali metal is boiled in an oven that is designed to direct a beam of alkaline metal vapour onto the hot plate. A high value of the hot plate work function and a low ionisation potential of the metal makes for a low potential barrier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
