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Rad50
DNA repair protein RAD50, also known as RAD50, is a protein that in humans is encoded by the ''RAD50'' gene. Function The protein encoded by this gene is highly similar to ''Saccharomyces cerevisiae'' Rad50, a protein involved in DNA double-strand break repair. This protein forms a complex with MRE11 and NBS1 (also known as Xrs2 in yeast). This MRN complex (MRX complex in yeast) binds to broken DNA ends and displays numerous enzymatic activities that are required for double-strand break repair by nonhomologous end-joining or homologous recombination. Gene knockout studies of the mouse homolog of Rad50 suggest it is essential for cell growth and viability. Two alternatively spliced transcript variants of Rad50, which encode distinct proteins, have been reported. Structure Rad50 is a member of the structural maintenance of chromosomes (SMC) family of proteins. Like other SMC proteins, Rad50 contains a long internal coiled-coil domain that folds back on itself, bringing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRN Complex
The MRN complex (MRX complex in yeast) is a protein complex consisting of Mre11, Rad50 and Nbs1 (also known as Nibrin in humans and as Xrs2 in yeast). In eukaryotes, the MRN/X complex plays an important role in the initial processing of double-strand DNA breaks prior to repair by homologous recombination or non-homologous end joining. The MRN complex binds avidly to double-strand breaks both in vitro and in vivo and may serve to tether broken ends prior to repair by non-homologous end joining or to initiate DNA end resection prior to repair by homologous recombination. The MRN complex also participates in activating the checkpoint kinase ATM in response to DNA damage. Production of short single-strand oligonucleotides by Mre11 endonuclease activity has been implicated in ATM activation by the MRN complex. Evolutionary ancestry and biologic function The MRN complex has been mainly studied in eukaryotes. However, recent work shows that two of the three protein components of this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRE11A
Double-strand break repair protein MRE11 is an enzyme that in humans is encoded by the ''MRE11'' gene. The gene has been designated ''MRE11A'' to distinguish it from the pseudogene ''MRE11B'' that is nowadays named ''MRE11P1''. Function This gene encodes a nuclear protein involved in homologous recombination, telomere length maintenance, and DNA double-strand break repair. By itself, the protein has 3' to 5' exonuclease activity and endonuclease activity. The protein forms a complex with the RAD50 homolog; this complex is required for nonhomologous joining of DNA ends and possesses increased single-stranded DNA endonuclease and 3' to 5' exonuclease activities. In conjunction with a DNA ligase, this protein promotes the joining of noncomplementary ends in vitro using short homologies near the ends of the DNA fragments. This gene has a pseudogene on chromosome 3. Alternative splicing of this gene results in two transcript variants encoding different isoforms. Orthologs Mre11, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nibrin
Nibrin, also known as NBN or NBS1, is a protein which in humans is encoded by the ''NBN'' gene. Function Nibrin is a protein associated with the repair of double strand breaks (DSBs) which pose serious damage to a genome. It is a 754 amino acid protein identified as a member of the NBS1/hMre11/RAD50(N/M/R, more commonly referred to as MRN) double strand DNA break repair complex. This complex recognizes DNA damage and rapidly relocates to DSB sites and forms nuclear foci. It also has a role in regulation of N/M/R (MRN) protein complex activity which includes end-processing of both physiological and mutagenic DNA double strand breaks (DSBs). Cellular response to DSBs Cellular response is performed by damage sensors, effectors of lesion repair and signal transduction. The central role is carried out by ataxia telangiectasia mutated (ATM) by activating the DSB signaling cascade, phosphorylating downstream substrates such as histone H2AX and NBS1. NBS1 relocates to DSB sites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BRCA1
Breast cancer type 1 susceptibility protein is a protein that in humans is encoded by the ''BRCA1'' () gene. Orthologs are common in other vertebrate species, whereas invertebrate genomes may encode a more distantly related gene. ''BRCA1'' is a human tumor suppressor gene (also known as a caretaker gene) and is responsible for repairing DNA. ''BRCA1'' and '' BRCA2'' are unrelated proteins, but both are normally expressed in the cells of breast and other tissue, where they help repair damaged DNA, or destroy cells if DNA cannot be repaired. They are involved in the repair of chromosomal damage with an important role in the error-free repair of DNA double-strand breaks. If ''BRCA1'' or ''BRCA2'' itself is damaged by a BRCA mutation, damaged DNA is not repaired properly, and this increases the risk for breast cancer. ''BRCA1'' and ''BRCA2'' have been described as "breast cancer susceptibility genes" and "breast cancer susceptibility proteins". The predominant allele has a norm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RINT1
RAD50-interacting protein 1 is a protein that in humans is encoded by the ''RINT1'' gene. Interactions RINT1 has been shown to interact with Rad50 DNA repair protein RAD50, also known as RAD50, is a protein that in humans is encoded by the ''RAD50'' gene. Function The protein encoded by this gene is highly similar to ''Saccharomyces cerevisiae'' Rad50, a protein involved in DNA double- ... and ZW10. References Further reading * * * * * * * * * * {{gene-7-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ATP-binding Cassette Transporter
The ATP-binding cassette transporters (ABC transporters) are a transport system superfamily that is one of the largest and possibly one of the oldest gene families. It is represented in all extant phyla, from prokaryotes to humans. ABC transporters belong to translocases. ABC transporters often consist of multiple subunits, one or two of which are transmembrane proteins and one or two of which are membrane-associated AAA ATPases. The ATPase subunits utilize the energy of adenosine triphosphate (ATP) binding and hydrolysis to provide the energy needed for the translocation of substrates across membranes, either for uptake or for export of the substrate. Most of the uptake systems also have an extracytoplasmic receptor, a solute binding protein. Some homologous ATPases function in non-transport-related processes such as translation of RNA and DNA repair. ABC transporters are considered to be an ABC superfamily based on the similarities of the sequence and organization of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homologous Recombination
Homologous recombination is a type of genetic recombination in which genetic information is exchanged between two similar or identical molecules of double-stranded or single-stranded nucleic acids (usually DNA as in cellular organisms but may be also RNA in viruses). Homologous recombination is widely used by cells to accurately DNA repair harmful breaks that occur on both strands of DNA, known as double-strand breaks (DSB), in a process called homologous recombinational repair (HRR). Homologous recombination also produces new combinations of DNA sequences during meiosis, the process by which eukaryotes make gamete cells, like sperm and egg cells in animals. These new combinations of DNA represent genetic variation in offspring, which in turn enables populations to adapt during the course of evolution. Homologous recombination is also used in horizontal gene transfer to exchange genetic material between different strains and species of bacteria and viruses. Horizon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TERF2
Telomeric repeat-binding factor 2 is a protein that is present at telomeres throughout the cell cycle. It is also known as TERF2, TRF2, and TRBF2, and is encoded in humans by the ''TERF2'' gene. It is a component of the shelterin nucleoprotein complex and a second negative regulator of telomere length, playing a key role in the protective activity of telomeres. It was first reported in 1997 in the lab of Titia de Lange, where a DNA sequence similar, but not identical, to TERF1 was discovered, with respect to the Myb-domain. De Lange isolated the new Myb-containing protein sequence and called it TERF2. Structure and domains TERF2 has a similar structure to that of TERF1. Both proteins carry a C-terminus Myb motif and large TERF1-related dimerization domains near their N-terminus. However, both proteins exist exclusively as homodimers and do not heterodimerize with each other, as proven by co-immunoprecipitation assay analysis. Also, TERF2 has a basic N-terminus, differing f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SMC Proteins
SMC complexes represent a large family of ATPases that participate in many aspects of higher-order chromosome organization and dynamics. SMC stands for Structural Maintenance of Chromosomes. Classification Eukaryotic SMCs Eukaryotes have at least six SMC proteins in individual organisms, and they form three distinct heterodimers with specialized functions: * A pair of SMC1 and SMC3 constitutes the core subunits of the cohesin complexes involved in sister chromatid cohesion. * Likewise, a pair of SMC2 and SMC4 acts as the core of the condensin complexes implicated in chromosome condensation. * A dimer composed of SMC5 and SMC6 functions as part of a yet-to-be-named complex implicated in DNA repair and checkpoint responses. Each complex contains a distinct set of non-SMC regulatory subunits. Some organisms have variants of SMC proteins. For instance, mammals have a meiosis-specific variant of SMC1, known as SMC1β. The nematode ''Caenorhabditis elegans'' has an SMC4-variant t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TERF2IP
Telomeric repeat-binding factor 2-interacting protein 1 also known as repressor activator protein 1 (Rap1) is a protein that in humans is encoded by the ''TERF2IP'' gene. Interactions TERF2IP has been shown to interact with Ku80, Rad50 DNA repair protein RAD50, also known as RAD50, is a protein that in humans is encoded by the ''RAD50'' gene. Function The protein encoded by this gene is highly similar to ''Saccharomyces cerevisiae'' Rad50, a protein involved in DNA double- ... and TERF2. Upon interaction, TERF2IP/TERF2 complex has been shown to bind to telomeric junction sites with higher affinity References Further reading * * * * * * * * * * * * * * * * * * {{gene-16-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfolobus
''Sulfolobus'' is a genus of microorganism in the family Sulfolobaceae. It belongs to the archaea domain. ''Sulfolobus'' species grow in volcanic springs with optimal growth occurring at pH 2-3 and temperatures of 75-80 °C, making them acidophiles and thermophiles respectively. ''Sulfolobus'' cells are irregularly shaped and flagellar. Species of ''Sulfolobus'' are generally named after the location from which they were first isolated, e.g. ''Sulfolobus solfataricus'' was first isolated in the Solfatara volcano. Other species can be found throughout the world in areas of volcanic or geothermal activity, such as geological formations called mud pots, which are also known as ''solfatare'' (plural of solfatara). ''Sulfolobus'' as a model to study the molecular mechanisms of DNA replication When the first Archaeal genome, ''Methanococcus jannaschii'', had been sequenced completely in 1996, it was found that the genes in the genome of ''Methanococcus jannaschii'' involved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
