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TRIM5
Tripartite motif-containing protein 5 also known as RING finger protein 88 is a protein that in humans is encoded by the ''TRIM5'' gene. The alpha isoform of this protein, TRIM5α, is a retrovirus restriction factor, which mediates a species-specific early block to retrovirus infection. TRIM5α is composed of 493 amino acids which is found in the cells of most primates. TRIM5α is an intrinsic immune factor important in the innate immune defense against retroviruses, along with the APOBEC family of proteins, tetherin and TRIM22. Structure TRIM5α belongs to the TRIM protein family (TRIM stands for TRIpartite Motif); this family was first identified by Reddy in 1992 as a set of proteins which contain a RING type zinc finger domain, a B-box zinc binding domain, followed by a coiled-coil region. TRIM5α bears the C-terminal PRY-SPRY or B30.2 domain in addition to the other domains. Function and means of action When a retrovirus enters the host cell cytosol, the retroviral ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripartite Motif Family
The tripartite motif family (TRIM) is a protein family. Function Many TRIM proteins are induced by interferons, which are important component of resistance to pathogens and several TRIM proteins are known to be required for the restriction of infection by lentiviruses. TRIM proteins are involved in pathogen-recognition and by regulation of transcriptional pathways in host defence. Structure The tripartite motif is always present at the N-terminus of the TRIM proteins. The TRIM motif includes the following three domains: * (1) a RING finger domain * (2) one or two B-box zinc finger domains ** when only one B-box is present, it is always a type-2 B-box ** when two B-boxes are present the type-1 B-Box always precedes the type-2 B-Box * (3) coiled coil region The C-terminus of TRIM proteins contain either: * Group 1 proteins: a C-terminal domain selected from the following list: ** NHL and IGFLMN domains, either in association or alone ** PHD domain associated with a bromodomain ** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RING Finger Domain
In molecular biology, a RING (short for Really Interesting New Gene) finger domain is a protein structural domain of zinc finger type which contains a C3HC4 amino acid motif which binds two zinc cations (seven cysteines and one histidine arranged non-consecutively). This protein domain contains 40 to 60 amino acids. Many proteins containing a RING finger play a key role in the ubiquitination pathway. Zinc fingers Zinc finger (Znf) domains are relatively small protein motifs that bind one or more zinc atoms, and which usually contain multiple finger-like protrusions that make tandem contacts with their target molecule. They bind DNA, RNA, protein and/or lipid substrates. Their binding properties depend on the amino acid sequence of the finger domains and of the linker between fingers, as well as on the higher-order structures and the number of fingers. Znf domains are often found in clusters, where fingers can have different binding specificities. There are many superfamilies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PtERV1
Pan troglodytes endogenous retrovirus-1 (PtERV1), or chimpanzee endogenous retrovirus-1 (CERV1), is a retrovirus that putatively infected chimpanzees about 4 million years ago, and may have been involved in the process of speciation, making the chimpanzee and human lines diverge. Kaiser ''et al.'' have suggested that TRIM5alpha, TRIM5α may have played a critical role in the human immune defense system about 4 million years ago, when the retrovirus was infecting chimpanzees. While no trace of PtERV1 has yet been found in the human genome, about 130 traces of PtERV1 DNA have been found in the genome of modern chimpanzees. After recreating part of the PtERV1 retrovirus, it was reported that TRIM5α prevents the virus from entering human cells ''in vitro''. While this cellular defense mechanism may have been very useful 4 million years ago when facing a PtERV1 epidemic, it has the side effect of leaving cells more susceptible to attack by the HIV-1 retrovirus. Recently, doubt has b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRIM22
Tripartite motif-containing 22, also known as TRIM22, is a protein which in humans is encoded by the ''TRIM22'' gene. Function The protein encoded by this gene is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. This protein localizes to the cytoplasm and its expression is induced by interferon. TRIM22 is also a target gene of the tumor suppressor protein p53. TRIM22 possesses E3 ubiquitin ligase activity and is able to ubiquitinate itself with the assistance of the E2 enzyme UbcH5B. Furthermore, TRIM22 is located in the nucleus and therefore may function as a nuclear E3 ubiquitin ligase. Clinical significance The protein down-regulates transcription from the HIV-1 long terminal repeat promoter region, suggesting that function of this protein may be to mediate interferon's antiviral effects. Other proteins that function to restrict HIV replication i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptidylprolyl Isomerase A
Peptidylprolyl isomerase A (PPIA), also known as cyclophilin A (CypA) or rotamase A is an enzyme that in humans is encoded by the ''PPIA'' gene on chromosome 7. As a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family, this protein catalyzes the cis-trans isomerization of proline imidic peptide bonds, which allows it to regulate many biological processes, including intracellular signaling, transcription, inflammation, and apoptosis. Due to its various functions, PPIA has been implicated in a broad range of inflammatory diseases, including atherosclerosis and arthritis, and viral infections. Structure PPIA is an 18 kDa, 165-amino acid long cytosolic protein. Like other cyclophilins, PPIA forms a β-barrel structure with a hydrophobic core. This β-barrel is composed of eight anti-parallel β-strands and capped by two α-helices at the top and bottom. In addition, the β-turns and loops in the strands contribute to the flexibility of the barrel. Its active site is a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Owl Monkey
Night monkeys, also known as owl monkeys or douroucoulis (), are nocturnal New World monkeys of the genus ''Aotus'', the only member of the family Aotidae (). The genus comprises eleven species which are found across Panama and much of South America in primary and secondary forests, tropical rainforests and cloud forests up to . Night monkeys have large eyes which improve their vision at night, while their ears are mostly hidden, giving them their name ''Aotus'', meaning "earless". Night monkeys are the only truly nocturnal monkeys with the exception of some cathemeral populations of Azara's night monkey, who have irregular bursts of activity during day and night. They have a varied repertoire of vocalisations and live in small family groups of a mated pair and their immature offspring. Night monkeys have monochromatic vision which improves their ability to detect visual cues at night. Night monkeys are threatened by habitat loss, the pet trade, hunting for bushmeat, and by bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code, or its genotype, and the influence of environmental factors. Both factors may interact, further affecting phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book ''The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as cad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murine Leukemia Virus
The murine leukemia viruses (MLVs or MuLVs) are retroviruses named for their ability to cause cancer in murine (mouse) hosts. Some MLVs may infect other vertebrates. MLVs include both exogenous and endogenous viruses. Replicating MLVs have a positive sense, single-stranded RNA (ssRNA) genome that replicates through a DNA intermediate via the process of reverse transcription. Classification The murine leukemia viruses are group/type VI retroviruses belonging to the gammaretroviral genus of the Retroviridae family. The viral particles of replicating MLVs have C-type morphology as determined by electron microscopy. The MLVs include both exogenous and endogenous viruses. Exogenous forms are transmitted as new infections from one host to another. The Moloney, Rauscher, Abelson and Friend MLVs, named for their discoverers, are used in cancer research. Endogenous MLVs are integrated into the host's germ line and are passed from one generation to the next. Stoye and Coffin hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-terminal Domain
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is translated from messenger RNA, it is created from N-terminus to C-terminus. The convention for writing peptide sequences is to put the C-terminal end on the right and write the sequence from N- to C-terminus. Chemistry Each amino acid has a carboxyl group and an amine group. Amino acids link to one another to form a chain by a dehydration reaction which joins the amine group of one amino acid to the carboxyl group of the next. Thus polypeptide chains have an end with an unbound carboxyl group, the C-terminus, and an end with an unbound amine group, the N-terminus. Proteins are naturally synthesized starting from the N-terminus and ending at the C-terminus. Function C-terminal retention signals While the N-terminus of a protein often c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New World Monkey
New World monkeys are the five families of primates that are found in the tropical regions of Mexico, Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Ceboidea (), the only extant superfamily in the parvorder Platyrrhini (). Platyrrhini is derived from the Greek for "broad nosed", and their noses are flatter than those of other simians, with sideways-facing nostrils. Monkeys in the family Atelidae, such as the spider monkey, are the only primates to have prehensile tails. New World monkeys' closest relatives are the other simians, the Catarrhini ("down-nosed"), comprising Old World monkeys and apes. New World monkeys descend from African simians that colonized South America, a line that split off about 40 million years ago. Evolutionary history About 40 million years ago, the Simiiformes infraorder split into the parvorders Platyrrhini (New World monkeys) and Catarrhini (apes and Old World mon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteasome
Proteasomes are protein complexes which degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds. Enzymes that help such reactions are called proteases. Proteasomes are part of a major mechanism by which cells regulate the concentration of particular proteins and degrade misfolded proteins. Proteins are tagged for degradation with a small protein called ubiquitin. The tagging reaction is catalyzed by enzymes called ubiquitin ligases. Once a protein is tagged with a single ubiquitin molecule, this is a signal to other ligases to attach additional ubiquitin molecules. The result is a ''polyubiquitin chain'' that is bound by the proteasome, allowing it to degrade the tagged protein. The degradation process yields peptides of about seven to eight amino acids long, which can then be further degraded into shorter amino acid sequences and used in synthesizing new proteins. Proteasomes are found inside all eukaryotes and archaea, and in so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swiss Institute Of Bioinformatics
The SIB Swiss Institute of Bioinformatics is an academic not-for-profit foundation which federates bioinformatics activities throughout Switzerland. The institute was established on 30 March 1998 and its mission is to provide core bioinformatics resources to the national and international life science research community in fields such as genomics, proteomics and systems biology as well as to lead and coordinate the field of bioinformatics in Switzerland. In particular, it promotes research, develops databanks and computer technologies, and is involved in teaching and service activities. History The institute was originally created to provide a framework for stable long-term funding for both the Swiss-Prot database and the Swiss EMBnet node. Swiss-Prot in particular went through a major funding crisis in 1996, which led the leaders of the five research groups active in bioinformatics in Geneva and Lausanne, Ron Appel, Amos Bairoch, Philipp Bucher, Victor Jongeneel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
