Rabbit Anti-Bloom Syndrome (BLM, BS, RECQ2, RECQL2)
BLM, a member of the RecQ family of DNA helicases, is part of the BRCA1-associated genome surveillance complex (BASC) that responds to DNA damage, stalled replication forks and S phase arrest (1-4). Phosphorylation of BLM helicase at Thr99 and Thr122 occurs in response to genotoxic stress (4), and phosphorylation of Ser144 appears to be important in regulating chromosome stability during mitosis (5). Typical BLM protein resides in the nucleus and forms part of a dynamic protein complex that acts in response to DNA damage during specific periods of the cell cycle (6). Although RecQ helicases are rarely considered as essential enzymes, they function at the interface between DNA recombination and repair and are required for global genome stability maintenance. Mutations in BLM helicase are responsible for development of Bloom Syndrome, a recessive genetic disorder clinically characterized by short stature, immunodeficiency and elevated risk of malignancy (7). Similar alterations to genes encoding the related RecQ helicases RecQ4 and WRN also result in recessive genetic disorders associated with genomic instability (8,9). Cells from Bloom Syndrome patients exhibit genomic instability and increased frequency of sister chromatid exchange (10).
Mutations of the gene for BLM have previously been associated with Bloom's syndrome, a disorder characterized by growth deficiency, chromosomal instability, and a predisposition to various cancers. Studies have implicated the BLM protein, an enzyme with potential roles in DNA replication, recombination, and chromosome segregation.
Bloom syndrome is a rare autosomal recessive disorder characterized by telangiectases and photosensitivity, growth deficiency of prenatal onset, variable degrees of immunodeficiency, and increased susceptibility to neoplasms of many sites and types. The New York dermatologist David Bloom first described the syndrome in 1954. The syndrome is caused by a mutation in the gene designated BLM, traced to band 15q26.1. The protein encoded by the normal gene has DNA helicase activity and functions in the maintenance of genomic stability. Increased sister chromatid exchanges and chromosomal instability also occur, which is assumed to be responsible for the phenotype and the cancer predisposition. In 1989, Nicotera et al suggested that the major biochemical defect in persons with Bloom syndrome is chronic overproduction of the superoxide radical anion. They thought that inefficient removal of peroxide might be responsible for the high rates of sister chromatid exchange and chromosomal damage in Bloom syndrome cells. More than 170 case reports have been made. The frequency of parental consanguinity is much greater than in the general population.
Bloom syndrome is more common in Ashkenazi Jews but has been reported in Japan and other countries. Early diagnosis of leukemia is, at present, not known to improve the chances of curative therapy. Frequent hematologic examinations in children is not advised for fear of untoward psychologic effects. Allogeneic marrow grafting has not been performed in Bloom syndrome patients. Men with Bloom syndrome are sterile; women have reduced fertility and a shortened reproductive span. Bloom syndrome patients who become pregnant are at high risk for premature delivery. Intelligence is usually normal, although mild deficiency has occurred in a few affected persons. Diabetes occurs in approximately 10% of individuals with Bloom syndrome. Bloom syndrome is more common in eastern European Ashkenazi Jews. The male-to-female ratio is 1.3:1. This condition occurs in the first few months of life.
Applications
Suitable for use in Western Blot. Other applications not tested.
Recommended Dilution
Western Blot: 1:1000, incubate membrane with diluted antibody in 5% w/v BSA, 1X TBS, 0.1% Tween-20 at 4°C with gentle shaking, overnight. Optimal dilutions to be determined by the researcher.
Storage and Stability
For long-term storage, aliquot and store at -20°C. Aliquots are stable for at least 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
Immunogen
Synthetic peptide corresponding to residues near the N-terminus of human BLM.
Form
Supplied as a liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, 0.1mg/ml BSA, 50% glycerol.
Purity
Purified by peptide affinity chromatography.
Specificity
Detects endogenous levels of total BLM protein.
