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Toll Like Receptor
Toll-like receptors (TLRs) are a class of proteins that play a key role in the innate immune system. They are single-pass membrane-spanning receptors usually expressed on sentinel cells such as macrophages and dendritic cells, that recognize structurally conserved molecules derived from microbes. Once these microbes have reached physical barriers such as the skin or intestinal tract mucosa, they are recognized by TLRs, which activate immune cell responses. The TLRs include TLR1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, TLR10, TLR11, TLR12, and TLR13. Humans lack genes for TLR11, TLR12 and TLR13 and mice lack a functional gene for TLR10. TLR1, TLR2, TLR4, TLR5, TLR6, and TLR10 are located on the cell membrane, whereas TLR3, TLR7, TLR8, and TLR9 are located in intracellular vesicles (because they are sensors of nucleic acids). TLRs received their name from their similarity to the protein coded by the toll gene. Function The ability of the immune syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TLR9
Toll-like receptor 9 is a protein that in humans is encoded by the ''TLR9'' gene. TLR9 has also been designated as CD289 (cluster of differentiation 289). It is a member of the toll-like receptor (TLR) family. TLR9 is an important receptor expressed in immune system cells including dendritic cells, macrophages, natural killer cells, and other antigen presenting cells. TLR9 preferentially binds DNA present in bacteria and viruses, and triggers signaling cascades that lead to a pro-inflammatory cytokine response. Cancer, infection, and tissue damage can all modulate TLR9 expression and activation. TLR9 is also an important factor in autoimmune diseases, and there is active research into synthetic TLR9 agonists and antagonists that help regulate autoimmune inflammation. Function The TLR family plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are named for the high degree of conservation in structure and function seen between mammalian TLRs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TLR4
Toll-like receptor 4 is a protein that in humans is encoded by the ''TLR4'' gene. TLR4 is a transmembrane protein, member of the toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. Its activation leads to an intracellular signaling pathway NF-κB and inflammatory cytokine production which is responsible for activating the innate immune system. TLR4 expressing cells are myeloid (erythrocytes, granulocytes, macrophages) rather than lymphoid (T-cells, B-cells, NK cells). Most myeloid cells also express high levels of CD14, which facilitates activation of TLR4 by LPS. It is most well known for recognizing lipopolysaccharide (LPS), a component present in many Gram-negative bacteria (e.g. ''Neisseria'' spp.) and selected Gram-positive bacteria. Its ligands also include several viral proteins, polysaccharide, and a variety of endogenous proteins such as low-density lipoprotein, beta-defensins, and heat shock protein. Palmitic acid and lauric acid a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucine-rich Repeat
A leucine-rich repeat (LRR) is a protein structural motif that forms an α/β horseshoe fold. It is composed of repeating 20–30 amino acid stretches that are unusually rich in the hydrophobic amino acid leucine. These tandem repeats commonly fold together to form a solenoid protein domain, termed leucine-rich repeat domain. Typically, each repeat unit has beta strand- turn-alpha helix structure, and the assembled domain, composed of many such repeats, has a horseshoe shape with an interior parallel beta sheet and an exterior array of helices. One face of the beta sheet and one side of the helix array are exposed to solvent and are therefore dominated by hydrophilic residues. The region between the helices and sheets is the protein's hydrophobic core and is tightly sterically packed with leucine residues. Leucine-rich repeats are frequently involved in the formation of protein–protein interactions. Examples Leucine-rich repeat motifs have been identified in a large numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TLR6
Toll-like receptor 6 is a protein that in humans is encoded by the ''TLR6'' gene. TLR6 is a transmembrane protein, member of toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. TLR6 acts in a heterodimer form with toll-like receptor 2 (TLR2). Its ligands include multiple diacyl lipopeptides derived from gram-positive bacteria and mycoplasma and several fungal cell wall saccharides. After dimerizing with TLR2, the NF-κB intracellular signalling pathway is activated, leading to a pro-inflammatory cytokine production and activation of innate immune response. TLR6 has also been designated as CD286 (cluster of differentiation 286). Function The protein encoded by this gene is a member of the toll-like receptor (TLR) family which plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from Drosophila to humans and share structural and functional similarities. They recognize pathogen-associate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Melanogaster
''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly" or "pomace fly". Starting with Charles W. Woodworth's 1901 proposal of the use of this species as a model organism, ''D. melanogaster'' continues to be widely used for biological research in genetics, physiology, microbial pathogenesis, and life history evolution. As of 2017, five Nobel Prizes have been awarded to drosophilists for their work using the insect. ''D. melanogaster'' is typically used in research owing to its rapid life cycle, relatively simple genetics with only four pairs of chromosomes, and large number of offspring per generation. It was originally an African species, with all non-African lineages having a common origin. Its geographic range includes all continents, including islands. ''D. melanogaster'' is a common pest in homes, restaurants, and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Future Microbiology
''Future Microbiology'' is a peer-reviewed medical journal that was established in 2006 and is published by Future Medicine. The editors-in-chief are Richard A. Calderone (Georgetown University) and B. Brett Finlay (University of British Columbia). The journal covers all aspects of the microbiological sciences, including virology, bacteriology, parasitology, and mycology. Abstracting and indexing The journal is abstracted and indexed in BIOSIS Previews, Biotechnology Citation Index, CAB Abstracts, Chemical Abstracts, Elsevier Biobase, EMBASE/Excerpta Medica, Index Medicus/MEDLINE/PubMed, Science Citation Index Expanded, and Scopus. According to the ''Journal Citation Reports'', the journal has a 2017 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 3.190, ranking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleic Acid
Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). If the sugar is ribose, the polymer is RNA; if the sugar is the ribose derivative deoxyribose, the polymer is DNA. Nucleic acids are naturally occurring chemical compounds that serve as the primary information-carrying molecules in cells and make up the genetic material. Nucleic acids are found in abundance in all living things, where they create, encode, and then store information of every living cell of every life-form on Earth. In turn, they function to transmit and express that information inside and outside the cell nucleus to the interior operations of the cell and ultimately to the next generation of each living organism. The encoded information is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vesicle (biology And Chemistry)
In cell biology, a vesicle is a structure within or outside a cell, consisting of liquid or cytoplasm enclosed by a lipid bilayer. Vesicles form naturally during the processes of secretion (exocytosis), uptake ( endocytosis) and transport of materials within the plasma membrane. Alternatively, they may be prepared artificially, in which case they are called liposomes (not to be confused with lysosomes). If there is only one phospholipid bilayer, the vesicles are called ''unilamellar liposomes''; otherwise they are called ''multilamellar liposomes''. The membrane enclosing the vesicle is also a lamellar phase, similar to that of the plasma membrane, and intracellular vesicles can fuse with the plasma membrane to release their contents outside the cell. Vesicles can also fuse with other organelles within the cell. A vesicle released from the cell is known as an extracellular vesicle. Vesicles perform a variety of functions. Because it is separated from the cytosol, the inside of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracellular Receptor
Intracellular receptors are Globular protein receptors located inside the cell rather than on its cell membrane. The word ''intracellular'' means "within or inside a cell". Molecules that cross a cell membrane to bind with a receptor are generally nonpolar and may be relatively small. These molecules are also known as ligands. Hormones that use intracellular receptors include thyroid, aldosterone, and steroid hormones. Examples are the class of nuclear receptors located in the cell nucleus and cytoplasm and the IP3 receptor located on the endoplasmic reticulum. The ligands that bind to them are usually intracellular second messengers like inositol trisphosphate (IP3) and extracellular lipophilic hormones like steroid hormones. Some intracrine peptide hormones also have intracellular receptors. Examples * transcription factors ** nuclear receptors * other ** Sigma1 (neurosteroids) ** IP3 receptor (inositol triphosphate, IP3) See also * Receptor * Steroid hormone A stero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Membrane
The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures. The membrane also contains membrane proteins, including integral proteins that span the membrane and serve as membrane transporters, and peripheral proteins that loosely attach to the outer (peripheral) side of the cell membrane, acting as enzymes to facilitate interaction with the cell's environment. Glycolipids embedded in the outer lipid layer serve a similar purpose. The cell membrane controls the movement of substances in and out of cells and organelles, being selectively permeable to ions a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TLR12
Toll-like receptor 1 (TIL) is a member of the toll-like receptor family (TLR) of pattern recognition receptors of the innate immune system. TIL recognizes pathogen-associated molecular pattern with a specificity for gram-positive bacteria. TIL has also been designated as CD281 (cluster of differentiation 281). TLRs are highly conserved from ''Drosophila'' to humans and share structural and functional similarities. They recognize pathogen-associated molecular patterns (PAMPs) that are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. The various TLRs exhibit different patterns of expression. This gene is ubiquitously expressed, and at higher levels than other TLR genes. Different length transcripts presumably resulting from use of alternative polyadenylation site, and/or from alternative splicing, have been noted for this gene. TLR1 recognizes peptidoglycan and (triacyl) lipopeptides in concert with TLR2 (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
