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Excision Repair Cross-complementing
Excision repair cross-complementing (ERCC) is a set of proteins which are involved in DNA repair. In humans, ERCC proteins are transcribed from the following genes: ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, ERCC6, and ERCC8. Members 1 though 5 are associated with Xeroderma Pigmentosum. Members 6 and 8 are associated with Cockayne syndrome Cockayne syndrome (CS), also called Neill-Dingwall syndrome, is a rare and fatal autosomal recessive neurodegenerative disorder characterized by growth failure, impaired development of the nervous system, abnormal sensitivity to sunlight (photosen .... References DNA repair {{protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Repair
DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as radiation can cause DNA damage, resulting in tens of thousands of individual molecular lesions per cell per day. Many of these lesions cause structural damage to the DNA molecule and can alter or eliminate the cell's ability to transcribe the gene that the affected DNA encodes. Other lesions induce potentially harmful mutations in the cell's genome, which affect the survival of its daughter cells after it undergoes mitosis. As a consequence, the DNA repair process is constantly active as it responds to damage in the DNA structure. When normal repair processes fail, and when cellular apoptosis does not occur, irreparable DNA damage may occur, including double-strand breaks and DNA crosslinkages (interstrand crosslinks or ICLs). This can eventually lead to malignant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC1
DNA excision repair protein ERCC-1 is a protein that in humans is encoded by the ''ERCC1'' gene. Together with ERCC4, ERCC1 forms the ERCC1-XPF enzyme complex that participates in DNA repair and DNA recombination. Many aspects of these two gene products are described together here because they are partners during DNA repair. The ERCC1-XPF nuclease is an essential activity in the pathway of DNA nucleotide excision repair (NER). The ERCC1-XPF nuclease also functions in pathways to repair double-strand breaks in DNA, and in the repair of “crosslink” damage that harmfully links the two DNA strands. Cells with disabling mutations in ''ERCC1'' are more sensitive than normal to particular DNA damaging agents, including ultraviolet (UV) radiation and to chemicals that cause crosslinking between DNA strands. Genetically engineered mice with disabling mutations in ERCC1 have defects in DNA repair, accompanied by metabolic stress-induced changes in physiology that result in premature a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC2
__NOTOC__ ERCC2, or XPD is a protein involved in transcription-coupled nucleotide excision repair. The XPD (ERCC2) gene encodes for a 2.3-kb mRNA containing 22 exons and 21 introns. The XPD protein contains 760 amino acids and is a polypeptide with a size of 87kDa. Defects in this gene can result in three different disorders: the cancer-prone syndrome xeroderma pigmentosum complementation group D, photosensitive trichothiodystrophy, and Cockayne syndrome. Just like XPB, XPD is a part of human transcriptional initiation factor TFIIH and has ATP-dependent helicase activity. It belongs to the RAD3/XPD subfamily of helicases. XPD is essential for the viability of cells. Deletion of XPD in mice is lethal for developing embryos. Consequences of mutations in ERCC2 The ERCC2/XPD protein participates in nucleotide excision repair and is used in unwinding the DNA double helix after damage is initially identified. Nucleotide excision repair is a multi-step pathway that removes a wide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC4
ERCC4 is a protein designated as DNA repair endonuclease XPF that in humans is encoded by the ''ERCC4'' gene. Together with ERCC1, ERCC4 forms the ERCC1-XPF enzyme complex that participates in DNA repair and DNA recombination. The nuclease enzyme ERCC1-XPF cuts specific structures of DNA. Many aspects of these two gene products are described together here because they are partners during DNA repair. The ERCC1-XPF nuclease is an essential activity in the pathway of DNA nucleotide excision repair (NER). The ERCC1-XPF nuclease also functions in pathways to repair double-strand breaks in DNA, and in the repair of "crosslink" damage that harmfully links the two DNA strands. Cells with disabling mutations in ''ERCC4'' are more sensitive than normal to particular DNA damaging agents, including ultraviolet radiation and to chemicals that cause crosslinking between DNA strands. Genetically engineered mice with disabling mutations in ''ERCC4'' also have defects in DNA repair, accompanie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC5
DNA repair protein complementing XP-G cells is a protein that in humans is encoded by the ''ERCC5'' gene. Function Excision repair cross-complementing rodent repair deficiency, complementation group 5 (xeroderma pigmentosum, complementation group G) is involved in excision repair of UV-induced DNA damage. Mutations cause Cockayne syndrome, which is characterized by severe growth defects, mental retardation, and cachexia. Multiple alternatively spliced transcript variants encoding distinct isoforms have been described, but the biological validity of all variants has not been determined. Mutations in ERCC5 cause arthrogryposis. XPG is a structure specific endonuclease that incises DNA at the 3’ side of the damaged nucleotide during nucleotide excision repair. Syndromes Mutational defects in the ''Ercc5''(''Xpg'') gene can cause either the cancer-prone condition xeroderma pigmentosum (XP) alone, or in combination with the severe neurodevelopmental disorder Cockayne syndrome (C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC6
DNA excision repair protein ERCC-6 (also CS-B protein) is a protein that in humans is encoded by the ''ERCC6'' gene. The ''ERCC6'' gene is located on the long arm of chromosome 10 at position 11.23.NIH. "ERCC6 Gene." Genetics Home Reference. National Institutes of Health, 16 Feb. 2015. Web. 22 Feb. 2015. . Having 1 or more copies of a mutated ERCC6 causes Cockayne syndrome, type II. Function DNA can be damaged by ultraviolet radiation, toxins, radioactive substances, and reactive biochemical intermediates like free radicals. The ERCC6 protein is involved in repairing the genome when specific genes undergoing transcription (dubbed ''active genes'') are inoperative; as such, ERCC6 serves as a transcription-coupled excision repair protein, being one of the fundamental enzymes in active gene repair. Structure and Mechanism CSB has been found to exhibit ATPase properties; there are contradictory publications regarding the effect of ATP concentration on CSB's activity. The most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ERCC8 (gene)
DNA excision repair protein ERCC-8 is a protein that in humans is encoded by the ''ERCC8'' gene. This gene encodes a WD repeat protein, which interacts with the Cockayne syndrome type B (CSB) and p44 proteins, the latter being a subunit of the RNA polymerase II transcription factor II H. Mutations in this gene have been identified in patients with the hereditary disease Cockayne syndrome (CS). CS is an accelerated aging disorder characterized by photosensitivity, impaired development and multi-system progressive degeneration. The CS cells are abnormally sensitive to ultraviolet radiation and are defective in the repair of transcriptionally active genes. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. CS arises from germline mutations in either of two genes ''CSA(ERCC8)'' or ''CSB(ERCC6)''. ''CSA'' mutations generally give rise to a more moderate form of CS than ''CSB'' mutations. Mutations in the ''CSA'' gene account ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xeroderma Pigmentosum
Xeroderma pigmentosum (XP) is a genetic disorder in which there is a decreased ability to repair DNA damage such as that caused by ultraviolet (UV) light. Symptoms may include a severe sunburn after only a few minutes in the sun, freckling in sun-exposed areas, dry skin and changes in skin pigmentation. Nervous system problems, such as hearing loss, poor coordination, loss of intellectual function and seizures, may also occur. Complications include a high risk of skin cancer, with about half having skin cancer by age 10 without preventative efforts, and cataracts. There may be a higher risk of other cancers such as brain cancers. XP is autosomal recessive, with mutations in at least nine specific genes able to result in the condition. Normally, the damage to DNA which occurs in skin cells from exposure to UV light is repaired by nucleotide excision repair. In people with xeroderma pigmentosum, this damage is not repaired. As more abnormalities form in DNA, cells malfunction and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cockayne Syndrome
Cockayne syndrome (CS), also called Neill-Dingwall syndrome, is a rare and fatal autosomal recessive neurodegenerative disorder characterized by growth failure, impaired development of the nervous system, abnormal sensitivity to sunlight (photosensitivity), eye disorders and premature aging.Bender M, Potocki L, Metry D. What syndrome is this? Cockayne syndrome. Pediatric Dermatology erial online November 2003;20(6):538-540. Available from: MEDLINE with Full Text, Ipswich, MA. Accessed April 30, 2015. Failure to thrive and neurological disorders are criteria for diagnosis, while photosensitivity, hearing loss, eye abnormalities, and cavities are other very common features. Problems with any or all of the internal organs are possible. It is associated with a group of disorders called leukodystrophies, which are conditions characterized by degradation of neurological white matter. The underlying disorder is a defect in a DNA repair mechanism. Unlike other defects of DNA repair, pati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
