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LIM Domain
LIM domains are protein structural domains, composed of two contiguous zinc fingers, separated by a two-amino acid residue hydrophobic linker. The domain name is an acronym of the three genes in which it was first identified (LIN-11, Isl-1 and MEC-3). LIM is a protein interaction domain that is involved in binding to many structurally and functionally diverse partners. The LIM domain appeared in eukaryotes sometime prior to the most recent common ancestor of plants, fungi, amoeba and animals. In animal cells, LIM domain-containing proteins often shuttle between the cell nucleus where they can regulate gene expression, and the cytoplasm where they are usually associated with actin cytoskeletal structures involved in connecting cells together and to the surrounding matrix, such as stress fibers, focal adhesions and adherens junctions. Discovery LIM domains are named after their initial discovery in the three homeobox proteins that have the following functions: * Lin-11 – as ... [...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 residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 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 pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, have myocytes and are motility, able to move, can reproduce sexually, and grow from a hollow sphere of Cell (biology), cells, the blastula, during embryonic development. Animals form a clade, meaning that they arose from a single common ancestor. Over 1.5 million extant taxon, living animal species have been species description, described, of which around 1.05 million are insects, over 85,000 are molluscs, and around 65,000 are vertebrates. It has been estimated there are as many as 7.77 million animal species on Earth. Animal body lengths range from to . They have complex ecologies and biological interaction, interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Motility
Motility is the ability of an organism to move independently using metabolism, metabolic energy. This biological concept encompasses movement at various levels, from whole organisms to cells and subcellular components. Motility is observed in animals, microorganisms, and even some plant structures, playing crucial roles in activities such as foraging, reproduction, and cellular functions. It is genetically determined but can be influenced by environmental factors. In multicellular organisms, motility is facilitated by systems like the Nervous system, nervous and Human musculoskeletal system, musculoskeletal systems, while at the cellular level, it involves mechanisms such as amoeboid movement and flagellar propulsion. These cellular movements can be directed by external stimuli, a phenomenon known as taxis. Examples include chemotaxis (movement along chemical gradients) and phototaxis (movement in response to light). Motility also includes physiological processes like gastroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cofilin
ADF/cofilin is a family of actin-binding proteins associated with the rapid depolymerization of Actin, actin microfilaments that give actin its characteristic dynamic instability. This dynamic instability is central to actin's role in muscle contraction, cell motility and transcription regulation. Three highly conserved and highly (70%-82%) identical genes belonging to this family have been described in humans and mice: * CFL1, coding for cofilin 1 (non-muscle, or n-cofilin) * CFL2 (gene), CFL2, coding for cofilin 2 (found in muscle: m-cofilin) * Destrin, DSTN, coding for destrin, also known as ADF or actin depolymerizing factor Actin-binding proteins regulate assembly and disassembly of actin filaments.Cooper, G. M. and R. E. Hausman. ''The Cell: A Molecular Approach,'' 3rd ed. Washington DC: ASM Press 2004 pp.436-440. Cofilin, a member of the ADF/cofilin family is actually a protein with 70% sequence identity to destrin, making it part of the ADF/cofilin family of small ADP-bind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycetozoa
Mycetozoa is a polyphyletic grouping of slime molds. It was originally thought to be a monophyletic clade, but in 2010 it was discovered that protostelia are a polyphyletic group within Conosa. Classification It can be divided into dictyostelid, myxogastrid, and protostelid groups. The mycetozoan groups all fit into the unikont supergroup Amoebozoa, whereas most other slime molds fit into various bikont groups ( fonticulids are opisthokonts). Utility in research The dictyostelids are used as examples of cell communication and differentiation, and may provide insights into how multicellular organisms develop. '' Physarum polycephalum'' are useful for studying cytoplasmic streaming. They have also been used to study the biochemical events that surround mitosis, since all of the nuclei in a medium-sized plasmodium divide in synchrony. It has been observed that they can find their way through mazes by spreading out and choosing the shortest path, an interesting example ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Polarity
Cell polarity refers to spatial differences in shape, structure, and function within a cell. Almost all cell types exhibit some form of polarity, which enables them to carry out specialized functions. Classical examples of polarized cells are described below, including epithelial cells with apical-basal polarity, neurons in which signals propagate in one direction from dendrites to axons, and migrating cells. Furthermore, cell polarity is important during many types of asymmetric cell division to set up functional asymmetries between daughter cells. Many of the key molecular players implicated in cell polarity are well conserved. For example, in metazoan cells, the complex plays a fundamental role in cell polarity. While the biochemical details may vary, some of the core principles such as negative and/or positive feedback between different molecules are common and essential to many known polarity systems. Examples of polarized cells Epithelial cells Epithelial cells adhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoarchitecture
Cytoarchitecture (from Greek κύτος 'cell' and ἀρχιτεκτονική 'architecture'), also known as cytoarchitectonics, is the study of the cellular composition of the central nervous system's tissues under the microscope. Cytoarchitectonics is one of the ways to parse the brain, by obtaining sections of the brain using a microtome and staining them with chemical agents which reveal where different neurons are located. The study of the parcellation of ''nerve fibers'' (primarily axons) into layers forms the subject of myeloarchitectonics (from Greek μυελός 'marrow' and ἀρχιτεκτονική 'architecture'), an approach complementary to cytoarchitectonics. History of the cerebral cytoarchitecture Defining cerebral cytoarchitecture began with the advent of histology—the science of slicing and staining brain slices for examination. It is credited to the Viennese psychiatrist Theodor Meynert (1833–1892), who in 1867 noticed regional variations in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adherens Junction
In cell biology, adherens junctions (or zonula adherens, intermediate junction, or "belt desmosome") are protein complexes that occur at cell–cell junctions and cell–matrix junctions in epithelial and endothelial tissues, usually more basal than tight junctions. An adherens junction is defined as a cell junction whose cytoplasmic face is linked to the actin cytoskeleton. They can appear as bands encircling the cell (zonula adherens) or as spots of attachment to the extracellular matrix (focal adhesion). Adherens junctions uniquely disassemble in uterine epithelial cells to allow the blastocyst to penetrate between epithelial cells. A similar cell junction in non-epithelial, non-endothelial cells is the fascia adherens. It is structurally the same, but appears in ribbonlike patterns that do not completely encircle the cells. One example is in cardiomyocytes. Proteins Adherens junctions are composed of the following proteins: * cadherins. The cadherins are a family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN1 Zinc Finger
In molecular biology, the AN1-type zinc finger domain, which has a dimetal (zinc)-bound alpha/beta tertiary structure, fold. This domain was first identified as a zinc finger at the C terminus of AN1 SWISSPROT, a ubiquitin-like protein in ''Xenopus laevis''. The AN1-type zinc finger contains six conserved sequence, conserved cysteines and two histidines that could potentially coordinate 2 zinc atoms. Certain stress-associated proteins (SAP) contain AN1 domain, often in combination with A20 zinc finger domains (SAP8) or C2H2 domains (SAP16). For example, the Homo sapiens, human protein Znf216 has an A20 zinc-finger at the N terminus and an AN1 zinc-finger at the C terminus, acting to negatively Transcriptional regulation, regulate the NFkappaB gene activation, activation pathway and to Protein-protein interaction, interact with components of the immune response like RIP, IKKgamma and TRAF6. The Protein-protein interaction, interact of Znf216 with IKK-gamma and RIP is mediated by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B-box Zinc Finger
In molecular biology the B-box-type zinc finger domain is a short protein domain of around 40 amino acid residues in length. B-box zinc fingers can be divided into two groups, where types 1 and 2 B-box domains differ in their consensus sequence and in the spacing of the 7-8 zinc-binding residues. Several proteins contain both types 1 and 2 B-boxes, suggesting some level of cooperativity between these two domains. Occurrence B-box domains are found in over 1500 proteins from a variety of organisms. They are found in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). TRIM proteins contain a type 2 B-box domain, and may also contain a type 1 B-box. In proteins that do not contain RING or coiled-coil domains, the B-box domain is primarily type 2. Many type 2 B-box proteins are involved in ubiquitinylation. Proteins containing a B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallopeptidase
A metalloproteinase, or metalloprotease, is any protease enzyme whose catalytic mechanism involves a metal. An example is ADAM12 which plays a significant role in the fusion of muscle cells during embryo development, in a process known as myogenesis. Most metalloproteases require zinc, but some use cobalt. The metal ion is coordinated to the protein via three ligands. The ligands coordinating the metal ion can vary with histidine, glutamate, aspartate, lysine, and arginine. The fourth coordination position is taken up by a labile water molecule. Treatment with chelating agents such as EDTA leads to complete inactivation. EDTA is a metal chelator that removes zinc, which is essential for activity. They are also inhibited by the chelator orthophenanthroline. Classification There are two subgroups of metalloproteinases: * Exopeptidases, metalloexopeptidases ( EC number: 3.4.17). * Endopeptidases, metalloendopeptidases (3.4.24). Well known metalloendopeptidases include ADAM prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
