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DNA Damage Repair

DNA is the carrier of the genetic information that defines any living being. The genetic code fixed in DNA is crucial for processes on a subcellular scale up to the appearance and function of the organism as s whole. Nonetheless, DNA is constantly exposed to insults from endogenous sources such as hydrolysis, oxidation, alkylation, or replication errors. In addition, ionizing radiation, UV radiation, and a plethora of chemical reagents are external factors that threaten the integrity of DNA.

Unlike RNA and proteins, DNA is not being degraded and re-synthesized upon damage. Instead, various repair pathways are in existence to assure that the DNA remains intact. Francis Crick noted in 1974 that “we totally missed the possible role of enzymes in [DNA] repair. I later came to realize that DNA is so precious that probably many distinct mechanisms could exist.”

This presage holds true today: over a hundred genes have been characterized since that are involved in an intricate network of DNA repair pathways. DNA damage can be repaired via six different pathways depending on the nature of the lesion: chemical modifications, misincorporated nucleotides, and cross-links are reverted through direct reversal (DR), mismatch repair (MMR), and nucleotide excision repair mechanisms. DNA single strand breaks are being mended via base excision repair. Highly mutagenic DNA double strand breaks finally are repaired through a number of complex pathways that rely on homologous recombination (HR) with the sister chromatid (in the S or G2 phase of the cell cycle) or non-homologous end-joining (NHEJ) of both ends of the double strand break. In case a DNA lesion cannot be repaired in time, specialized DNA polymerases enable trans-lesion synthesis (TLS) in order to prevent the DNA replication fork from stalling. Mutations that render components of these repair pathways non-functional lead to diseases such as xeroderma pigmentosum, ataxia telangiectasia, Fanconi anemia, and a predisposition for cancer.

Besides, these repair mechanisms are of high interest for current targeted genome editing approaches that typically take advantage of the cellular DNA repair machinery.

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Canonical Non-Homologous End-Joining

PRKDC (Protein Kinase, DNA-Activated, Catalytic Polypeptide):

Immunohistochemical analysis of DNA-PKcs staining in human tonsil formalin fixed paraffin embedded tissue section. The section was pre-treated using heat mediated antigen retrieval with sodium citrate buffer (pH 6.0). The section was then incubated with the antibody at room temperature and detected using an HRP conjugated compact polymer system. DAB was used as the chromogen. The section was then counterstained with haematoxylin and mounted with DPX.

This gene encodes the catalytic subunit of the DNA-dependent protein kinase (DNA-PK). It functions with the Ku70/Ku80 heterodimer protein in DNA double strand break repair and recombination. The protein encoded is a member of the PI3/PI4-kinase family.[provided by RefSeq, Jul 2010]. More...

XRCC6 - X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 6

Immunofluorescence staining of ARIH2 in HeLa cells. Cells were fixed with 4% PFA,blocked with 10% serum, and incubated with rabbit anti-human ARIH2 polyclonal antibody (1 µg/ml) at 4℃ overnight. Then cells were stained with the Alexa Fluor®594-conjugated Goat Anti-rabbit IgG secondary antibody (green)Positive staining was localized to nucleus.

XRCC5 (X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 5 (Double-Strand-Break Rejoining)):

ATM (Ataxia Telangiectasia Mutated):

TRIM29 (Tripartite Motif Containing 29):

ATR (Ataxia Telangiectasia and Rad3 Related):

ATR Antibodies

H2AFX - H2A Histone Family, Member X:

XRCC4 (X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 4):

LIG4 - Ligase IV, DNA, ATP-Dependent:

NHEJ1 - Nonhomologous End-Joining Factor 1:

APTX - Aprataxin:

APLF (Aprataxin and PNKP Like Factor):

DCLRE1C (DNA Cross-Link Repair 1C):

PNKP (Polynucleotide Kinase 3'-Phosphatase):

DNTT - Deoxynucleotidyltransferase, terminal:

POLL (Polymerase (DNA Directed), lambda):

POLM - Polymerase (DNA Directed), mu:

MRE11A - MRE11 Meiotic Recombination 11 Homolog A (S. Cerevisiae):

RAD50 (RAD50 Homolog (S. Cerevisiae)):

NBN - Nibrin:

TP53BP1 (Tumor Protein P53 Binding Protein 1):

Microhomology-Mediated End-Joining

PARP1 (Poly (ADP-Ribose) Polymerase 1):

Immunochemical staining of human PARP1 in human brain with rabbit polyclonal antibody (0.5 µg/mL, formalin-fixed paraffin embedded sections).

This gene encodes a chromatin-associated enzyme, poly(ADP-ribosyl)transferase, which modifies various nuclear proteins by poly(ADP-ribosyl)ation. The modification is dependent on DNA and is involved in the regulation of various important cellular processes such as differentiation, proliferation, and tumor transformation and also in the regulation of the molecular events involved in the recovery... More...

LIG3 (Ligase III, DNA, ATP-Dependent):

LIG2 - Ligase II, DNA, ATP-Dependent:

PARP2 - Poly (ADP-Ribose) Polymerase 2:

LIG1 (Ligase I, DNA, ATP-Dependent):

ATM (Ataxia Telangiectasia Mutated):

TRIM29 (Tripartite Motif Containing 29):

ATR (Ataxia Telangiectasia and Rad3 Related):

ATR Antibodies

RBBP8 - Retinoblastoma Binding Protein 8:

MRE11A - MRE11 Meiotic Recombination 11 Homolog A (S. Cerevisiae):

RAD50 (RAD50 Homolog (S. Cerevisiae)):

NBN - Nibrin:

RECQL2 - RECQL2 (ARABIDOPSIS RECQ HELICASE L2), 3'-5' DNA Helicase/ ATP-Dependent Helicase/ Four-Way Junction Helicase/ Protein Binding:

RECQL2 Antibodies

Homologous Recombination

RAD51 (DNA Repair Protein Homolog 1):

The protein encoded by this gene is a member of the RAD51 protein family. RAD51 family members are highly similar to bacterial RecA and Saccharomyces cerevisiae Rad51, and are known to be involved in the homologous recombination and repair of DNA. This protein can interact with the ssDNA-binding protein RPA and RAD52, and it is thought to play roles in homologous pairing and strand transfer of... More...

BRCA1 (Breast Cancer 1):

Immunofluorescence staining of BRCA1 in HeLa cells. Cells were fixed with 4% PFA,blocked with 10% serum. Then incubated with rabbit anti-human BRCA1 polyclonal antibody (1 µg/ml)(Figure A), incubated with rabbit anti-human BRCA1 polyclonal antibody and antigen (Figure B) at 4℃ overnight. Then cells were stained with the Alexa Fluor®488-conjugated Goat Anti-rabbit IgG secondary antibody (green) and counterstained with DAPI (blue). Positive staining was localized to cytoplasm and nucleus.

BRCA2 (Breast Cancer 2, Early Onset):

Immunohistochemical analysis of BRCA2 staining in human breast cancer formalin fixed paraffin embedded tissue section. The section was pre-treated using heat mediated antigen retrieval with sodium citrate buffer (pH 6.0). The section was then incubated with the antibody at room temperature and detected using an HRP conjugated compact polymer system. DAB was used as the chromogen. The section was then counterstained with haematoxylin and mounted with DPX.

POLE (Polymerase (DNA Directed), Epsilon, Catalytic Subunit):

POLE Antibodies

POLE2 - Polymerase (DNA Directed), epsilon 2 (p59 Subunit):

POLE3 - Polymerase (DNA Directed), epsilon 3 (p17 Subunit):

POLE4 (Polymerase (DNA-Directed), epsilon 4 (p12 Subunit)):

POLD1 - Polymerase (DNA Directed), delta 1, Catalytic Subunit 125kDa:

POLD2 (Polymerase (DNA Directed), delta 2, Accessory Subunit):

POLD3 - Polymerase (DNA-Directed), delta 3, Accessory Subunit:

POLD4 (Polymerase (DNA-Directed), delta 4, Accessory Subunit):

ATM (Ataxia Telangiectasia Mutated):

TRIM29 (Tripartite Motif Containing 29):

ATR (Ataxia Telangiectasia and Rad3 Related):

ATR Antibodies

Rad51B - RAD51 Homolog B (S. Cerevisiae):

RAD51C (RAD51 Homolog C (S. Cerevisiae)):

XRCC2 (X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 2):

XRCC3 (X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 3):

BRIP1 (BRCA1 Interacting Protein C-terminal Helicase 1):

BARD1 (BRCA1 Associated RING Domain 1):

RBBP8 - Retinoblastoma Binding Protein 8:

FAM175A - Family with Sequence Similarity 175, Member A:

UIMC1 - Ubiquitin Interaction Motif Containing 1:

MRE11A - MRE11 Meiotic Recombination 11 Homolog A (S. Cerevisiae):

RAD50 (RAD50 Homolog (S. Cerevisiae)):

NBN - Nibrin:

TP53BP1 (Tumor Protein P53 Binding Protein 1):

RPA1 - Replication Protein A1, 70kDa:

RPA2 (Replication Protein A2, 32kDa):

RPA3 (Replication Protein A3, 14kDa):

PALB2 (Partner and Localizer of BRCA2):

TOP3A (Topoisomerase (DNA) III alpha):

RMI1 (Homolog of Yeast RecQ-mediated Genome Instability 1):

RMI2 (RMI2, RecQ Mediated Genome Instability 2, Homolog (S. Cerevisiae)):

DNA2 (DNA Replication Helicase 2 Homolog (Yeast)):

DNA2 Antibodies

RECQL2 - RECQL2 (ARABIDOPSIS RECQ HELICASE L2), 3'-5' DNA Helicase/ ATP-Dependent Helicase/ Four-Way Junction Helicase/ Protein Binding:

RECQL2 Antibodies

RAD54L (RAD54-Like (S. Cerevisiae)):

MUS81 (MUS81 Endonuclease Homolog (S. Cerevisiae)):

SLX1B - SLX1 Structure-Specific Endonuclease Subunit Homolog B (S. Cerevisiae):

BTBD12 - BTB (POZ) Domain Containing 12:

BTBD12 Antibodies

GEN1 (Gen Endonuclease Homolog 1 (Drosophila)):

GEN1 Antibodies

Single Strand Annealing

(MSH2):

Antibodies

ERCC1 (Excision Repair Cross Complementing Polypeptide-1):

MSH3 (MutS Homolog 3 (E. Coli)):

MSH3 Antibodies

ERCC4 - Excision Repair Cross-Complementing Rodent Repair Deficiency, Complementation Group 4:

ATM (Ataxia Telangiectasia Mutated):

TRIM29 (Tripartite Motif Containing 29):

ATR (Ataxia Telangiectasia and Rad3 Related):

ATR Antibodies

MRE11A - MRE11 Meiotic Recombination 11 Homolog A (S. Cerevisiae):

RAD50 (RAD50 Homolog (S. Cerevisiae)):

NBN - Nibrin:

RPA1 - Replication Protein A1, 70kDa:

RPA2 (Replication Protein A2, 32kDa):

RPA3 (Replication Protein A3, 14kDa):

RAD52 (RAD52 Homolog (S. Cerevisiae)):

Break-Induced Replication

MCM2 - Minichromosome Maintenance Complex Component 2

Immunofluorescence analysis of HepG2 cells, using MCM2 antibody (ABIN5976452).

MCM7 - Minichromosome Maintenance Complex Component 7

Immunohistochemistry of Human colon cancer using MCM7 Polyclonal Antibody at dilution of 1:15

RAD51 (DNA Repair Protein Homolog 1):

MRE11A - MRE11 Meiotic Recombination 11 Homolog A (S. Cerevisiae):

RAD50 (RAD50 Homolog (S. Cerevisiae)):

NBN - Nibrin:

RPA1 - Replication Protein A1, 70kDa:

RPA2 (Replication Protein A2, 32kDa):

RPA3 (Replication Protein A3, 14kDa):

MCM3 (Minichromosome Maintenance Complex Component 3):

MCM4 (Minichromosome Maintenance Deficient 4):

MCM5 - Minichromosome Maintenance Complex Component 5:

MCM6 - Minichromosome Maintenance Complex Component 6:

Base Excision Repair

OGG1 (8-Oxoguanine DNA Glycosylase):

Immunofluorescence of purified MaxPab antibody to OGG1 on HeLa cell. (antibody concentration 10 ﾵg/mL)

This gene encodes the enzyme responsible for the excision of 8-oxoguanine, a mutagenic base byproduct which occurs as a result of exposure to reactive oxygen. The action of this enzyme includes lyase activity for chain cleavage. Alternative splicing of the C-terminal region of this gene classifies splice variants into two major groups, type 1 and type 2, depending on the last exon of the... More...

UNG (Uracil-DNA Glycosylase):

APEX1 - APEX Nuclease (Multifunctional DNA Repair Enzyme) 1

Human APEX1/APE1/Ref-1 Western blot (WB) 6521

MPG - N-Methylpurine-DNA Glycosylase:

SMUG1 - Single-Strand-Selective Monofunctional Uracil-DNA Glycosylase 1:

TDG - Thymine-DNA Glycosylase:

MBD4 (Methyl-CpG Binding Domain Protein 4):

MUTYH - MutY Homolog (E. Coli):

NEIL1 (Endonuclease VIII-Like 1):

NEIL2 (Nei Endonuclease VIII-Like 2 (E. Coli)):

NEIL3 (Nei Endonuclease VIII-Like 3 (E. Coli)):

POLB (Polymerase (DNA Directed), beta):

POLD1 - Polymerase (DNA Directed), delta 1, Catalytic Subunit 125kDa:

POLD2 (Polymerase (DNA Directed), delta 2, Accessory Subunit):

POLD3 - Polymerase (DNA-Directed), delta 3, Accessory Subunit:

POLD4 (Polymerase (DNA-Directed), delta 4, Accessory Subunit):

FEN1 (Flap Structure-Specific Endonuclease 1):

LIG1 (Ligase I, DNA, ATP-Dependent):

Nuleotide Excision Repair

POLR2B - Polymerase (RNA) II (DNA Directed) Polypeptide B, 140kDa

ICC/IF Image Immunofluorescence analysis of paraformaldehyde-fixed HeLa, using RPB2, antibody at 1:200 dilution.

This gene encodes the second largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. This subunit, in combination with at least two other polymerase subunits, forms a structure within the polymerase that maintains contact in the active site of the enzyme between the DNA template and the newly synthesized RNA. [provided by RefSeq, Jul 2008]. More...

POLR2B Antibodies

XPC (Xeroderma Pigmentosum, Complementation Group C):

DDB1 (Damage Specific DNA Binding Protein 1):

Western blot detection of DDB1 antibody in Hela, 3T3, C6, COS7, 293T and K562 cell lysates using DDB1 antibody (1:1000 diluted) .

XPA (Xeroderma Pigmentosum, Complementation Group A):

RAD23A (RAD23 Homolog A (S. Cerevisiae)):

RAD23B - RAD23 Homolog B (S. Cerevisiae):

CETN2 (Centrin, EF-Hand Protein, 2):

DDB2 (Damage-Specific DNA Binding Protein 2, 48kDa):

ERCC1 (Excision Repair Cross Complementing Polypeptide-1):

ERCC2 (Excision Repair Cross-Complementing Rodent Repair Deficiency, Complementation Group 2):

ERCC3 - DNA Repair Protein Complementing XP-B Cells:

GTF2H1 - General Transcription Factor IIH, Polypeptide 1, 62kDa:

GTF2H4 (General Transcription Factor IIH, Polypeptide 4, 52kDa):

GTF2H3 (General Transcription Factor IIH, Polypeptide 3, 34kD):

GTF2H5 - General Transcription Factor IIH, Polypeptide 5:

CDK7 (Cyclin-Dependent Kinase 7):

RFC1 - Replication Factor C (Activator 1) 1, 145kDa:

RFC2 (Replication Factor C (Activator 1) 2, 40kDa):

RFC3 - Replication Factor C (Activator 1) 3, 38kDa:

RFC4 (Replication Factor C (Activator 1) 4, 37kDa):

RFC5 (Replication Factor C (Activator 1) 5, 36.5kDa):

POLK - Polymerase (DNA Directed) kappa:

ERCC4 - Excision Repair Cross-Complementing Rodent Repair Deficiency, Complementation Group 4:

ERCC5 - DNA Repair Protein Complementing XP-G Cells:

ERCC6 (Excision Repair Cross-Complementing Rodent Repair Deficiency, Complementation Group 6):

ERCC8 (Excision Repair Cross-Complementing Rodent Repair Deficiency, Complementation Group 8):

POLE (Polymerase (DNA Directed), Epsilon, Catalytic Subunit):

POLE Antibodies

POLE2 - Polymerase (DNA Directed), epsilon 2 (p59 Subunit):

POLE3 - Polymerase (DNA Directed), epsilon 3 (p17 Subunit):

POLE4 (Polymerase (DNA-Directed), epsilon 4 (p12 Subunit)):

PCNA (Proliferating Cell Nuclear Antigen):

XRCC1 (X-Ray Repair Complementing Defective Repair in Chinese Hamster Cells 1):

FEN1 (Flap Structure-Specific Endonuclease 1):

LIG1 (Ligase I, DNA, ATP-Dependent):

RPA1 - Replication Protein A1, 70kDa:

RPA2 (Replication Protein A2, 32kDa):

RPA3 (Replication Protein A3, 14kDa):

Mismatch Repair

(MSH2):

This locus is frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). When cloned, it was discovered to be a human homolog of the E. coli mismatch repair gene mutS, consistent with the characteristic alterations in microsatellite sequences (RER+ phenotype) found in HNPCC. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]. More...

Antibodies

MSH3 (MutS Homolog 3 (E. Coli)):

Immunohistochemistry of Human colon cancer using MSH3 Polyclonal Antibody at dilution of 1:20

MSH3 Antibodies

MSH6 (MutS Homolog 6 (E. Coli)):

MLH1 (MutL Homolog 1, Colon Cancer, Nonpolyposis Type 2 (E. Coli)):

PMS2 (PMS2 Postmeiotic Segregation Increased 2 (S. Cerevisiae)):

RFC1 - Replication Factor C (Activator 1) 1, 145kDa:

RFC2 (Replication Factor C (Activator 1) 2, 40kDa):

RFC3 - Replication Factor C (Activator 1) 3, 38kDa:

RFC4 (Replication Factor C (Activator 1) 4, 37kDa):

RFC5 (Replication Factor C (Activator 1) 5, 36.5kDa):

POLD1 - Polymerase (DNA Directed), delta 1, Catalytic Subunit 125kDa:

POLD2 (Polymerase (DNA Directed), delta 2, Accessory Subunit):

POLD3 - Polymerase (DNA-Directed), delta 3, Accessory Subunit:

PCNA (Proliferating Cell Nuclear Antigen):

LIG1 (Ligase I, DNA, ATP-Dependent):

RPA1 - Replication Protein A1, 70kDa:

RPA2 (Replication Protein A2, 32kDa):

RPA3 (Replication Protein A3, 14kDa):

EXO1 - Exonuclease 1:

Direct Reversal

MGMT (O6-Methylguanine-DNA-Methyltransferase):

Involved in the cellular defense against the biological effects of O6-methylguanine (O6-MeG) in DNA. Repairs alkylated guanine in DNA by stoichiometrically transferring the alkyl group at the O-6 position to a cysteine residue in the enzyme. This is a More...

ALKBH - AlkB, Alkylation Repair Homolog 1 (E. Coli)

Immunofluorescence of purified MaxPab antibody to ALKBH on HeLa cell. [antibody concentration 10 ug/ml]

ALKBH2 - AlkB, Alkylation Repair Homolog 2

ALKBH3 - AlkB, Alkylation Repair Homolog 3 (E. Coli):

Trans-Lesion Synthesis

POLI - Polymerase (DNA Directed) iota

Western Blot analysis of POLI expression in transfected 293T cell line by POLI monoclonal antibody (M01), clone 8G9.Lane 1: POLI transfected lysate(80.3 KDa).Lane 2: Non-transfected lysate. Dilution: 1:500~1000

POLH - Polymerase (DNA Directed), eta