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RNA Extraction
RNA extraction is the purification of RNA from biological samples. This procedure is complicated by the ubiquitous presence of ribonuclease enzymes in cells and tissues, which can rapidly degrade RNA. Several methods are used in molecular biology to isolate RNA from samples, the most common of these is guanidinium thiocyanate-phenol-chloroform extraction. The filter paper based lysis and elution method features high throughput capacity. RNA extraction in liquid nitrogen, commonly using a mortar and pestle (or specialized steel devices known as tissue pulverizers) is also useful in preventing ribonuclease activity. RNase contamination The extraction of RNA in molecular biology experiments is greatly complicated by the presence of ubiquitous and hardy RNases that degrade RNA samples. Certain RNases can be extremely hardy and inactivating them is difficult compared to neutralizing DNases. In addition to the cellular RNases that are released there are several RNases that are present in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribonuclease
Ribonuclease (commonly abbreviated RNase) is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 (for the phosphorolytic enzymes) and 3.1 (for the hydrolytic enzymes) classes of enzymes. Function All organisms studied contain many RNases of two different classes, showing that RNA degradation is a very ancient and important process. As well as clearing of cellular RNA that is no longer required, RNases play key roles in the maturation of all RNA molecules, both messenger RNAs that carry genetic material for making proteins and non-coding RNAs that function in varied cellular processes. In addition, active RNA degradation systems are the first defense against RNA viruses and provide the underlying machinery for more advanced cellular immune strategies such as RNAi. Some cells also secrete copious quantities of non-specific RN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methods In Molecular Biology
''Methods in Molecular Biology'' is a book series published by Humana Press (an imprint of Springer Science+Business Media) that covers molecular biology research methods and protocols. The book series was introduced by series editor John M. Walker in 1983 and provides step-by-step instructions for carrying out experiments in a research lab. As of January 2020, more than 2000 volumes (2471 as of 10-March-2022) had been published in the series. The protocols are also available online in SpringerLink, and were previously in ''Springer Protocols ''Springer Protocols'' was a database of life sciences protocols published by Springer Science+Business Media. It replaced ''BioMed Protocols'', a Humana Press database, in January 2008, and was deactivated on 25 July 2018. The protocols were then ...''. Each protocol opens with an introductory overview and a list of the materials and reagents needed to complete the experiment. Every protocol is followed by a detailed procedure that is supp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guanidinium Thiocyanate-phenol-chloroform Extraction
Acid guanidinium thiocyanate-phenol-chloroform extraction (abbreviated AGPC) is a liquid–liquid extraction technique in biochemistry. It is widely used in molecular biology for isolating RNA (as well as DNA and protein in some cases). This method may take longer than a column-based system such as the silica-based purification, but has higher purity and the advantage of high recovery of RNA: an RNA column is typically unsuitable for purification of short (<200 ) RNA species, such as , , and |
DNase
Deoxyribonuclease (DNase, for short) refers to a group of glycoprotein endonucleases which are enzymes that catalyze the hydrolytic cleavage of phosphodiester linkages in the DNA backbone, thus degrading DNA. The role of the DNase enzyme in cells includes breaking down extracellular DNA (ecDNA) excreted by apoptosis, necrosis, and neutrophil extracellular traps (NET) of cells to help reduce inflammatory responses that otherwise are elicited. A wide variety of deoxyribonucleases are known and fall into one of two families (DNase I or DNase II), which differ in their substrate specificities, chemical mechanisms, and biological functions. Laboratory applications of DNase include purifying proteins when extracted from prokaryotic organisms. Additionally, DNase has been applied as a treatment for diseases that are caused by ecDNA in the blood plasma. Assays of DNase are emerging in the research field as well. Types The two main types of DNase found in metazoans are known as deoxyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNase A
Pancreatic ribonuclease family (, ''RNase'', ''RNase I'', ''RNase A'', ''pancreatic RNase'', ''ribonuclease I'', ''endoribonuclease I'', ''ribonucleic phosphatase'', ''alkaline ribonuclease'', ''ribonuclease'', ''gene S glycoproteins'', ''Ceratitis capitata alkaline ribonuclease'', ''SLSG glycoproteins'', ''gene S locus-specific glycoproteins'', ''S-genotype-assocd. glycoproteins'', ''ribonucleate 3'-pyrimidino-oligonucleotidohydrolase'') is a superfamily of pyrimidine-specific endonucleases found in high quantity in the pancreas of certain mammals and of some reptiles. Specifically, the enzymes are involved in endonucleolytic cleavage of 3'-phosphomononucleotides and 3'-phosphooligonucleotides ending in C-P or U-P with 2',3'-cyclic phosphate intermediates. Ribonuclease can unwind the RNA helix by complexing with single-stranded RNA; the complex arises by an extended multi-site cation-anion interaction between lysine and arginine residues of the enzyme and phosphate groups of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exaptation
Exaptation and the related term co-option describe a shift in the function of a trait during evolution. For example, a trait can evolve because it served one particular function, but subsequently it may come to serve another. Exaptations are common in both anatomy and behaviour. Bird feathers are a classic example. Initially they may have evolved for temperature regulation, but later were adapted for flight. When feathers were first used to aid in flight, that was an exaptive use. They have since then been shaped by natural selection to improve flight, so in their current state they are best regarded as adaptations for flight. So it is with many structures that initially took on a function as an exaptation: once molded for a new function, they become further adapted for that function. Interest in exaptation relates to both the process and products of evolution: the process that creates complex traits and the products (functions, anatomical structures, biochemicals, etc.) that may b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Column Purification
Spin column-based nucleic acid purification is a solid phase extraction method to quickly purify nucleic acids. This method relies on the fact that nucleic acid will bind to the solid phase of silica under certain conditions. Procedure The stages of the method are lyse, bind, wash, and elute. More specifically, this entails the lysis of target cells to release nucleic acids, selective binding of nucleic acid to a silica membrane, washing away particulates and inhibitors that are not bound to the silica membrane, and elution of the nucleic acid, with the end result being purified nucleic acid in an aqueous solution. For lysis, the cells (blood, tissue, etc.) of the sample must undergo a treatment to break the cell membrane and free the nucleic acid. Depending on the target material, this can include the use of detergent or other buffers, proteinases or other enzymes, heating to various times/temperatures, or mechanical disruption such as cutting with a knife or homogenizer, usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Extraction
The first isolation of deoxyribonucleic acid (DNA) was done in 1869 by Friedrich Miescher. Currently, it is a routine procedure in molecular biology or forensic analyses. For the chemical method, many different kits are used for extraction, and selecting the correct one will save time on kit optimization and extraction procedures. PCR sensitivity detection is considered to show the variation between the commercial kits. What does it deliver? DNA extraction is frequently a preliminary step in many diagnostic procedures used to identify environmental viruses and bacteria and diagnose illnesses and hereditary diseases. These methods consist of, but are not limited to: Fluorescence In Situ Hybridization (FISH) technique was developed in the 1980s. The basic idea is to use a nucleic acid probe to hybridize nuclear DNA from either interphase cells or metaphase chromosomes attached to a microscopic slide. It is a molecular method used, among other things, to recognize and count parti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol Precipitation
Ethanol precipitation is a method used to purify and/or concentrate RNA, DNA, and polysaccharides such as pectin and xyloglucan from aqueous solutions by adding ethanol as an antisolvent. DNA precipitation Theory DNA is polar due to its highly charged phosphate backbone. Its polarity makes it water-soluble (water is polar) according to the principle "like dissolves like". Because of the high polarity of water, illustrated by its high dielectric constant of 80.1 (at 20 °C), electrostatic forces between charged particles are considerably lower in aqueous solution than they are in a vacuum or in air. This relation is reflected in Coulomb's law, which can be used to calculate the force acting on two charges q_1 and q_2 separated by a distance r by using the dielectric constant \varepsilon_r (also called relative static permittivity) of the medium in the denominator of the equation (\varepsilon_0 is an electric constant): F = \frac \frac At an atomic level, the reduction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemical Separation Processes
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research. Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis which allows biological molecules to give rise to the processes that occur within living cells and between cells,Karp (2009), p. 2. in turn relating greatly to the understanding of tissues and organs, as well as organism structure and function.Miller (2012). p. 62. Biochemistry is closely related to molecular biology, which is the study of the molecular mechanisms of biological phenomena.Astb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
