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GSDMD
Gasdermin D (GSDMD) is a protein that in humans is encoded by the ''GSDMD'' gene on chromosome 8. It belongs to the gasdermin family which is conserved among vertebrates and comprises six members in humans, GSDMA, GSDMB, GSDMC, GSDMD, GSDME (DFNA5) and DFNB59 (Pejvakin). Members of the gasdermin family are expressed in a variety of cell types including epithelial cells and immune cells. GSDMA, GSDMB, GSDMC, GSDMD and GSDME have been suggested to act as tumour suppressors. Structure The structure of full-length GSDMD consists of two domains, the 31 kDa N-terminal (GSDMD-N) and 22 kDa C-terminal (GSDMD-C) domains, separated by a linker region. GSDMD-C can be divided into four subdomains and is composed of 10 α-helices and two β-strands, forming a compact globular fold. The linker helix contacts the two helix-repeats which consist of four-helix bundles. The middle domain comprises an antiparallel β-strand and a short α-helix. The first flexible loop of GSDMD-C, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroptosis
Pyroptosis is a highly inflammatory form of Lysis, lytic programmed cell death that occurs most frequently upon infection with intracellular pathogens and is likely to form part of the antimicrobial response. This process promotes the rapid clearance of various bacterial, viral, fungal and protozoan infections by removing intracellular replication niches and enhancing the host's defensive responses. Pyroptosis can take place in immune cells and is also reported to occur in keratinocytes and some epithelial cells. The process is initiated by formation of a large supramolecular complex termed the inflammasome (also known as a pyroptosome) upon intracellular danger signals. The inflammasome activates a different set of caspases as compared to apoptosis, for example, caspase-1/4/5 in humans and caspase-11 in mice. These caspases contribute to the maturation and activation of several proinflammatory cytokines and pore-forming protein GSDMD, gasdermins. Formation of pores causes cell membr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caspases
Caspases (cysteine-aspartic proteases, cysteine aspartases or cysteine-dependent aspartate-directed proteases) are a family of protease enzymes playing essential roles in programmed cell death. They are named caspases due to their specific cysteine protease activity – a cysteine in its active site nucleophilically attacks and cleaves a target protein only after an aspartic acid residue. As of 2009, there are 12 confirmed caspases in humans and 10 in mice, carrying out a variety of cellular functions. The role of these enzymes in programmed cell death was first identified in 1993, with their functions in apoptosis well characterised. This is a form of programmed cell death, occurring widely during development, and throughout life to maintain cell homeostasis. Activation of caspases ensures that the cellular components are degraded in a controlled manner, carrying out cell death with minimal effect on surrounding tissues. Caspases have other identified roles in programmed cell ... [...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] |
Substrate (chemistry)
In chemistry, the term substrate is highly context-dependent. Broadly speaking, it can refer either to a chemical species being observed in a chemical reaction, or to a surface on which other chemical reactions or microscopy are performed. In the former sense, a reagent is added to the ''substrate'' to generate a product through a chemical reaction. The term is used in a similar sense in synthetic and organic chemistry, where the substrate is the chemical of interest that is being modified. In biochemistry, an enzyme substrate is the material upon which an enzyme acts. When referring to Le Chatelier's principle, the substrate is the reagent whose concentration is changed. ;Spontaneous reaction : :*Where S is substrate and P is product. ;Catalysed reaction : :*Where S is substrate, P is product and C is catalyst. In the latter sense, it may refer to a surface on which other chemical reactions are performed or play a supporting role in a variety of spectroscopic and microsco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proinflammatory Cytokine
An inflammatory cytokine or proinflammatory cytokine is a type of signaling molecule (a cytokine) that is secreted from immune cells like helper T cells (Th) and macrophages, and certain other cell types that promote inflammation. They include interleukin-1 (IL-1), IL-6, IL-12, and IL-18, tumor necrosis factor alpha (TNF-α), interferon gamma (IFNγ), and granulocyte-macrophage colony stimulating factor (GM-CSF) and play an important role in mediating the innate immune response. Inflammatory cytokines are predominantly produced by and involved in the upregulation of inflammatory reactions. Excessive chronic production of inflammatory cytokines contribute to inflammatory diseases, that have been linked to different diseases, such as atherosclerosis and cancer. Dysregulation has also been linked to depression and other neurological diseases. A balance between proinflammatory and anti-inflammatory cytokines is necessary to maintain health. Aging and exercise also play a role in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogens
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the longest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracellular
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions from sub-disciplines and related fields, see Glossary of genetics, Glossary of evolutionary biology, Glossary of ecology, and Glossary of scientific naming, or any of the organism-specific glossaries in :Glossaries of biology. A B C D E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysis
Lysis ( ) is the breaking down of the membrane of a cell, often by viral, enzymic, or osmotic (that is, "lytic" ) mechanisms that compromise its integrity. A fluid containing the contents of lysed cells is called a ''lysate''. In molecular biology, biochemistry, and cell biology laboratories, cell cultures may be subjected to lysis in the process of purifying their components, as in protein purification, DNA extraction, RNA extraction, or in purifying organelles. Many species of bacteria are subject to lysis by the enzyme lysozyme, found in animal saliva, egg white, and other secretions. Phage lytic enzymes (lysins) produced during bacteriophage infection are responsible for the ability of these viruses to lyse bacterial cells. Penicillin and related β-lactam antibiotics cause the death of bacteria through enzyme-mediated lysis that occurs after the drug causes the bacterium to form a defective cell wall. If the cell wall is completely lost and the penicillin was used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection. Infections can be caused by a wide range of pathogens, most prominently bacteria and viruses. Hosts can fight infections using their immune system. Mammalian hosts react to infections with an innate response, often involving inflammation, followed by an adaptive response. Specific medications used to treat infections include antibiotics, antivirals, antifungals, antiprotozoals, and antihelminthics. Infectious diseases resulted in 9.2 million deaths in 2013 (about 17% of all deaths). The branch of medicine that focuses on infections is referred to as infectious disease. Types Infections are caused by infectious agents (pathogens) including: * Bacteria (e.g. ''Mycobacterium tuberculosis'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programmed Cell Death
Programmed cell death (PCD; sometimes referred to as cellular suicide) is the death of a cell as a result of events inside of a cell, such as apoptosis or autophagy. PCD is carried out in a biological process, which usually confers advantage during an organism's lifecycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate. PCD serves fundamental functions during both plant and animal tissue development. Apoptosis and autophagy are both forms of programmed cell death. Necrosis is the death of a cell caused by external factors such as trauma or infection and occurs in several different forms. Necrosis was long seen as a non-physiological process that occurs as a result of infection or injury, but in the 2000s, a form of programmed necrosis, called necroptosis, was recognized as an alternative form of programmed cell death. It is hypothesized that necroptosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effector (biology)
In biochemistry, an effector molecule is usually a small molecule that selectively binds to a protein and regulates its biological activity. In this manner, effector molecules act as ligands that can increase or decrease enzyme activity, gene expression, or cell signaling. Effector molecules can also directly regulate the activity of some mRNA molecules (riboswitches). Other examples of effector functions in biochemistry include hormone signaling and immune response. In some cases, specific proteins serve the same role as effector molecules (note: small molecules refers to organic compounds similar in size to amino acids or RNA strands. Most effector molecules are therefor much smaller than individual proteins, which consist of many amino acids). One example of this is in cellular signal transduction cascades. The term ''effector'' is used in other fields of biology. For instance, the effector end of a neuron is the terminus where an axon makes contact with the muscle or o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caspase 11
Murine caspase-11, and its human homologs caspase-4 and caspase-5, are mammalian intracellular receptor proteases activated by TLR4 and TLR3 signaling during the innate immune response. Caspase-11, also termed the non-canonical inflammasome, is activated by TLR3/TLR4- TRIF signaling and directly binds cytosolic lipopolysaccharide (LPS), a major structural element of Gram-negative bacterial cell walls. Activation of caspase-11 by LPS is known to cause the activation of other caspase proteins, leading to septic shock, pyroptosis, and often organismal death. History LPS is a known activator of innate immune responses. Extracellular LPS binds specifically to the cell surface receptor TLR4. LPS binding to TLR4 subsequently causes initiation of the MyD88 and TRIF signaling pathways, leading to expression of pro- inflammatory molecules and cytokines. These inflammatory mediators cause host toxic shock and sepsis as a result of an overactive immune response to LPS. Until recen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
