|
NEIL3 (gene)
Nei endonuclease VIII-like 3 (E. coli) is a protein in humans that is encoded by the NEIL3 gene. NEIL3 belongs to a class of DNA glycosylases homologous to the bacterial Fpg/Nei family. These glycosylases initiate the first step in base excision repair by cleaving bases damaged by reactive oxygen species and introducing a DNA strand break via the associated lyase reaction. See also * OGG1 * NTHL1 * NEIL1 * NEIL2 Endonuclease VIII-like 2 is an enzyme that in humans is encoded by the ''NEIL2'' gene. NEIL2 belongs to a class of DNA glycosylases homologous to the bacterial Fpg/Nei family. These glycosylases initiate the first step in base excision repair by ... References {{gene-4-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humans
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, and language. Humans are highly social and tend to live in complex social structures composed of many cooperating and competing groups, from families and kinship networks to political states. Social interactions between humans have established a wide variety of values, social norms, and rituals, which bolster human society. Its intelligence and its desire to understand and influence the environment and to explain and manipulate phenomena have motivated humanity's development of science, philosophy, mythology, religion, and other fields of study. Although some scientists equate the term ''humans'' with all members of the genus ''Homo'', in common usage, it generally refers to ''Homo sapiens'', the only extant member. Anatomically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosylases
Glycosylases ( EC 3.2) are enzymes that hydrolyze glycosyl compounds. They are a type of hydrolase (EC 3). In turn, glycosylases are divided into two groups: glycosidase Glycoside hydrolases (also called glycosidases or glycosyl hydrolases) catalyze the hydrolysis of glycosidic bonds in complex sugars. They are extremely common enzymes with roles in nature including degradation of biomass such as cellulose (c ...s—enzymes that hydrolyze O- and S-glycosyl compounds (EC 3.2.1) -- and enzymes that hydrolyze N-glycosyl compounds (EC 3.2.2). References {{Portal bar, Biology, border=no EC 3.2 Enzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterial
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationships ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Excision Repair
Base excision repair (BER) is a cellular mechanism, studied in the fields of biochemistry and genetics, that repairs damaged DNA throughout the cell cycle. It is responsible primarily for removing small, non-helix-distorting base lesions from the genome. The related nucleotide excision repair pathway repairs bulky helix-distorting lesions. BER is important for removing damaged bases that could otherwise cause mutations by mispairing or lead to breaks in DNA during replication. BER is initiated by DNA glycosylases, which recognize and remove specific damaged or inappropriate bases, forming AP sites. These are then cleaved by an AP endonuclease. The resulting single-strand break can then be processed by either short-patch (where a single nucleotide is replaced) or long-patch BER (where 2–10 new nucleotides are synthesized). Lesions processed by BER Single bases in DNA can be chemically damaged by a variety of mechanisms, the most common ones being deamination, oxidation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reactive Oxygen
In chemistry, reactive oxygen species (ROS) are highly Reactivity (chemistry), reactive chemicals formed from diatomic oxygen (). Examples of ROS include peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha-oxygen. The reduction of molecular oxygen () produces superoxide (), which is the Precursor (chemistry), precursor to most other reactive oxygen species: :O2 + e^- -> \ ^\bullet O2- Dismutation of superoxide produces hydrogen peroxide (): :2 H+ + \ ^\bullet O2^- + \ ^\bullet O2^- -> H2O2 + O2 Hydrogen peroxide in turn may be partially reduced, thus forming hydroxide ions and hydroxyl radicals (), or fully reduced to water: :H2O2 + e^- -> HO^- + \ ^\bullet OH :2 H+ + 2 e- + H2O2 -> 2 H2O In a biological context, ROS are byproducts of the normal metabolism of oxygen. ROS have roles in cell signaling and homeostasis. ROS are intrinsic to cellular functioning, and are present at low and stationary levels in normal cells. In plants, ROS are involved in metabolic pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NTHL1
Endonuclease III-like protein 1 is an enzyme that in humans is encoded by the ''NTHL1'' gene. As reviewed by Li et al., NTHL1 is a bifunctional DNA glycosylase that has an associated beta-elimination activity. NTHL1 is usually involved in removing oxidative pyrimidine lesions through base excision repair. NTHL1 catalyses the first step in base excision repair. It cleaves the N-glycosylic bond between the damaged base and its associated sugar residue and then cleaves the phosphodiester bond 3' to the AP site, leaving a 3'-unsaturated aldehyde after beta-elimination and a 5'-phosphate at the termini of the repair gap. Low expression of NTHL1 is associated with initiation and development of astrocytoma. Low expression of NTHL1 is also found in follicular thyroid tumors. A germ line homozygous mutation in ''NTHL1'' causes a cancer susceptibility syndrome similar to Lynch syndrome Hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome is an autosomal dominant ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NEIL1
Endonuclease VIII-like 1 is an enzyme that in humans is encoded by the ''NEIL1'' gene. NEIL1 belongs to a class of DNA glycosylases homologous to the bacterial Fpg/Nei family. These glycosylases initiate the first step in base excision repair by cleaving bases damaged by reactive oxygen species (ROS) and introducing a DNA strand break via the associated lyase reaction. Targets NEIL1 recognizes (targets) and removes certain ROS-damaged bases and then incises the abasic site via β,δ elimination, leaving 3′ and 5′ phosphate ends. NEIL1 recognizes oxidized pyrimidines, formamidopyrimidines, thymine residues oxidized at the methyl group, and both stereoisomers of thymine glycol. The best substrates for human NEIL1 appear to be the hydantoin lesions, guanidinohydantoin, and spiroiminodihydantoin that are further oxidation products of 8-oxoG. NEIL1 is also capable of removing lesions from single-stranded DNA as well as from bubble and forked DNA structures. Because the expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
