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Nucleosome Core Particle 1EQZ V
A nucleosome is the basic structural unit of DNA packaging in eukaryotes. The structure of a nucleosome consists of a segment of DNA wound around eight histone proteins and resembles thread wrapped around a spool. The nucleosome is the fundamental subunit of chromatin. Each nucleosome is composed of a little less than two turns of DNA wrapped around a set of eight proteins called histones, which are known as a histone octamer. Each histone octamer is composed of two copies each of the histone proteins H2A, H2B, H3, and H4. DNA must be compacted into nucleosomes to fit within the cell nucleus. In addition to nucleosome wrapping, eukaryotic chromatin is further compacted by being folded into a series of more complex structures, eventually forming a chromosome. Each human cell contains about 30 million nucleosomes. Nucleosomes are thought to carry epigenetically inherited information in the form of covalent modifications of their core histones. Nucleosome positions in the gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basic Units Of Chromatin Structure
Basic or BASIC may refer to: Science and technology * BASIC, a computer programming language * Basic (chemistry), having the properties of a base * Basic access authentication, in HTTP Entertainment * ''Basic'' (film), a 2003 film * Basic, one of the languages in ''Star Wars'' Music * ''Basic'' (Glen Campbell album), 1978 * ''Basic'' (Robert Quine and Fred Maher album), 1984 * ''B.A.S.I.C.'' (Alpinestars album), 2000 * ''Basic'' (Brown Eyed Girls album), 2015 * ''B.A.S.I.C.'' (The Basics album), 2019 Places * Basic, Mississippi, a community in the US * BASIC countries, Brazil, South Africa, India and China in climate change negotiations Organizations * BASIC Bank Limited, government owned bank in Bangladesh * Basic Books, an American publisher Other uses * Basic (cigarette), a brand of cigarettes manufactured by the Altria Group (Philip Morris Company) * Basic (dance move), the dance move that defines the character of a particular dance * Basic (slang), a pejorative t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The Complementarity (molecular biology), complementary nature of this based-paired structure provides a Redundancy (information theory), redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apoptotic DNA Laddering
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemical events lead to characteristic cell changes (morphology) and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, DNA fragmentation, and mRNA decay. The average adult human loses 50 to 70 billion cells each day due to apoptosis. For the average human child between 8 and 14 years old, each day the approximate loss is 20 to 30 billion cells. In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle. For example, the separation of fingers and toes in a developing human embryo occurs because cells between the digits undergo a form of apoptosis that is genetically determined. Unlike necrosis, apoptosis produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root Mean Square Deviation
The root mean square deviation (RMSD) or root mean square error (RMSE) is either one of two closely related and frequently used measures of the differences between true or predicted values on the one hand and observed values or an estimator on the other. The deviation is typically simply a differences of scalars; it can also be generalized to the vector lengths of a displacement, as in the bioinformatics concept of root mean square deviation of atomic positions. RMSD of a sample The RMSD of a sample is the quadratic mean of the differences between the observed values and predicted ones. These deviations are called '' residuals'' when the calculations are performed over the data sample that was used for estimation (and are therefore always in reference to an estimate) and are called ''errors'' (or prediction errors) when computed out-of-sample (aka on the full set, referencing a true value rather than an estimate). The RMSD serves to aggregate the magnitudes of the errors in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palindromic Sequence
A palindromic sequence is a nucleic acid sequence in a double-stranded DNA or RNA molecule whereby reading in a certain direction (e.g. 5' to 3') on one strand is identical to the sequence in the same direction (e.g. 5' to 3') on the complementary strand. This definition of palindrome thus depends on complementary strands being palindromic of each other. The meaning of palindrome in the context of genetics is slightly different from the definition used for words and sentences. Since a double helix is formed by two paired antiparallel strands of nucleotides that run in opposite directions, and the nucleotides always pair in the same way (adenine (A) with thymine (T) in DNA or uracil (U) in RNA; cytosine (C) with guanine (G)), a (single-stranded) nucleotide sequence is said to be a palindrome if it is equal to its reverse complement. For example, the DNA sequence ACCTAGGT is palindromic with its nucleotide-by-nucleotide complement TGGATCCA because reversing the order of the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centromere
The centromere links a pair of sister chromatids together during cell division. This constricted region of chromosome connects the sister chromatids, creating a short arm (p) and a long arm (q) on the chromatids. During mitosis, spindle fibers attach to the centromere via the kinetochore. The physical role of the centromere is to act as the site of assembly of the kinetochores – a highly complex multiprotein structure that is responsible for the actual events of chromosome segregation – i.e. binding microtubules and signaling to the cell cycle machinery when all chromosomes have adopted correct attachments to the spindle, so that it is safe for cell division to proceed to completion and for cells to enter anaphase. There are, broadly speaking, two types of centromeres. "Point centromeres" bind to specific proteins that recognize particular DNA sequences with high efficiency. Any piece of DNA with the point centromere DNA sequence on it will typically form a centr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ETH Zurich
ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ranks among Europe's best universities. Like its sister institution École Polytechnique Fédérale de Lausanne, EPFL, ETH Zurich is part of the ETH Domain, Swiss Federal Institutes of Technology Domain, a consortium of universities and research institutes under the Swiss Federal Department of Economic Affairs, Education and Research. , ETH Zurich enrolled 25,380 students from over 120 countries, of which 4,425 were pursuing doctoral degrees. Students, faculty, and researchers affiliated with ETH Zurich include 22 Nobel Prize, Nobel laureates, two Fields Medalists, three Pritzker Architecture Prize, Pritzker Prize winners, and one Turing Award, Turing Award recipient, including Albert Einstein and John von Neumann. It is a founding member o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Structure
In crystallography, crystal structure is a description of ordered arrangement of atoms, ions, or molecules in a crystalline material. Ordered structures occur from intrinsic nature of constituent particles to form symmetric patterns that repeat along the principal directions of three-dimensional space in matter. The smallest group of particles in a material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive translation of the unit cell along its principal axes. The translation vectors define the nodes of the Bravais lattice. The lengths of principal axes/edges, of the unit cell and angles between them are lattice constants, also called ''lattice parameters'' or ''cell parameters''. The symmetry properties of a crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleosome 1KX5 Colour Coded
A nucleosome is the basic structural unit of DNA packaging in eukaryotes. The structure of a nucleosome consists of a segment of DNA wound around eight histone, histone proteins and resembles thread wrapped around a bobbin, spool. The nucleosome is the fundamental subunit of chromatin. Each nucleosome is composed of a little less than two turns of DNA wrapped around a set of eight proteins called histones, which are known as a histone octamer. Each histone octamer is composed of two copies each of the histone proteins Histone H2A, H2A, Histone H2B, H2B, Histone H3, H3, and Histone H4, H4. DNA must be compacted into nucleosomes to fit within the cell nucleus. In addition to nucleosome wrapping, eukaryotic chromatin is further compacted by being folded into a series of more complex structures, eventually forming a chromosome. Each human cell contains about 30 million nucleosomes. Nucleosomes are thought to carry Epigenetics, epigenetically inherited information in the form of coval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaea
Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even though the domain Archaea Cladistics, cladistically includes eukaryotes, the term "archaea" (: archaeon , from the Greek "ἀρχαῖον", which means ancient) in English still generally refers specifically to prokaryotic members of Archaea. Archaea were initially Taxonomy (biology), classified as bacteria, receiving the name archaebacteria (, in the Archaebacteria Kingdom (biology), kingdom), but this term has fallen out of use. Archaeal cells have unique properties separating them from Bacteria and Eukaryote, Eukaryota. Archaea are further divided into multiple recognized phylum, phyla. Classification is difficult because most have not been Isolation (microbiology), isolated in a laboratory and have been detected only by their Gene, gene s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protamines
Protamines are small, arginine-rich, nuclear proteins that replace histones late in the haploid phase of spermatogenesis and are believed essential for sperm head condensation and DNA stabilization. They may allow for denser packaging of DNA in the spermatozoon than histones, but they must be decompressed before the genetic data can be used for protein synthesis. However, part of the sperm's genome is packaged by histones (10-15% in humans and other primates) thought to bind genes that are essential for early embryonic development. Protamine and protamine-like (PL) proteins are collectively known as the sperm-specific nuclear basic proteins (SNBPs). The PL proteins are intermediate in structure between protamine and Histone H1. The C-terminal domain of PL could be the precursor of vertebrate protamine. Spermatogenesis During the formation of sperm, protamine binds to the phosphate backbone of DNA using the arginine-rich domain as an anchor. DNA is then folded into a toroid, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Microscope
An electron microscope is a microscope that uses a beam of electrons as a source of illumination. It uses electron optics that are analogous to the glass lenses of an optical light microscope to control the electron beam, for instance focusing it to produce magnified images or electron diffraction patterns. As the wavelength of an electron can be up to 100,000 times smaller than that of visible light, electron microscopes have a much higher Angular resolution, resolution of about 0.1 nm, which compares to about 200 nm for optical microscope, light microscopes. ''Electron microscope'' may refer to: * Transmission electron microscopy, Transmission electron microscope (TEM) where swift electrons go through a thin sample * Scanning transmission electron microscopy, Scanning transmission electron microscope (STEM) which is similar to TEM with a scanned electron probe * Scanning electron microscope (SEM) which is similar to STEM, but with thick samples * Electron microprobe sim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
