Ataxia-telangiectasia

In patients with ataxia-telangiectasia, an autosomal recessive disease in humans resulting in the development of cerebellar ataxia and lymphoreticular neoplasms, there appears to exist an increased sensitivity to damage by x-ray. Patients with Fanconi s anemia, an autosomal recessive anemia characterized also by an increased frequency of cancer and by chromosomal instability, probably have defective repair of cross-linking damage. 

Down s syndrome Bloom s syndrome Fanconi s anemia Klinefelter s syndrome Ataxia telangiectasia Langerhans cell histiocytosis Shwachman s syndrome Severe combined... 

Ataxia telangiectasia mutated (ATM), poly(ADP ribose) polymerase (PARP), DNA-dependent protein kinase, DNA replication factor C, DNA topoisomerase I, DNA fragmentation factor (DFF)45, inhibitor of caspase-activated DNAse (ICAD), lamins A, Bl, and C TRAF-1, Rafl, Ras, GAP, GDP dissociation inhibitor of Rho family GTPases, phospholipase A2, Statl... 

The invariant SQ motif in the C-terminus of H2AX is a consensus sequence for the 3 kinases belonging to the PIKK family, namely ATM, DNA-PK and ATR (Stiff et al, 2004). These kinases are involved in DNA repair. ATM [ataxia telangiectasia (A-T) mutated protein] is a crucial kinase for the signal transduction DSB pathway (Savitsky et al, 1995) and it is widely accepted that ATM is the major kinase involved in the in vivo phosphorylation of H2AX (Burma et al, 2001 Fernandez-Capetillo et al, 2002 Redon et al, 2002). The two other kinases were also associated with the generation y-H2AX, but they appeared not to be dominant (Redon et al, 2002 Stiff et al, 2004). 

ATM Ataxia telangiectasia mutated. Kinase, plays a key role in repair of double-stranded DNA breaks. 

Ataxia telangiectasia like disease (ATLD) Mrell... 

Boder E, Sedgwick RP (1958) Ataxia-telangiectasia a familial syndrome of progressive cerebellar ataxia, oculocutaneous telangiectasia and frequent pulmonary infection. Pediatrics 21(4) 526-554 Brown EJ, Baltimore D (2003) Essential and dispensable roles of ATR in cell cycle arrest and genome maintenance. Genes Dev 17(5) 615-628... 

O Driscoll M, Ruiz-Perez VL, Woods CG, Jeggo PA, Goodship JA (2003) A splicing mutation affecting expression of ataxia-telangiectasia and Rad3-related protein (ATR) results in Seckel syndrome. Nat Genet 33(4) 497-501... 

SI39 (for mammals). The responsible kinases are members from phosphatidyli-nositol 3-kinase (PI3K)-like family kinases, which include ataxia telangiectasia mutated (ATM), AT-related (ATR), and DNA dependent protein kinase (DNA-PK) (Burma et al, 2001 Stiff et al, 2004 van Attikum and Gasser, 2005). Histone H2AX phosphorylation is directly related to repair of damaged chromatin (for details see chapter on Role of histone phosphorylation in chromatin dynamics and its implication in diseases ). 

ATM gene encodes a kinase essential for p53 activity. ATM is inactivated in ataxia telangiectasia, characterized by hypersensitivity to x-rays and predisposition to lymphomas. 

Fig. 2. Mechanisms causing resistance to antitumor treatment. ATM. ataxia telangiectasia gene, (Westphal et al., 1998 Xu and Baltimore, 1996), bcl-2/bax (Farrow and Brown, 1996, Zunino et al., 1997 Haq and Zanke, 1998), bcr/abl (McGahon et al., 1994), BCRP, breast cancer resistance protein (Doyle et d., 1998 Ross et al, 1999) bleomycin hydrolase (El-Deiry, 1997), BRCAl (Husain et al., 1998 Chen et al., 1998), BRCA2 (Chen et al., 1998 Chen et 1999), c-abl (White and Prives, 1999), c-jun (Sanchez-Perez and Perona, 1999), cytidine deaminase (El-Deiry, 1997), DNA poip, DNA polymerase p (Ochs et al., 1999), dihydrofolate reductase (Schimke, 1986), DT-diaphorase (Riley and Workman, 1992 Fitzsimmons et al., 1996 El-Deiry, 1997), EGR-1 (Ahmed et al., 1996), fos (Niimi et al., 1991), glucosylceramide synthase...

Natarajan, A.T., Verdegaal-lmmerzeel, E.A.M., Ashwood-Smifh, M.J. and Poulton, G.A. (1981) Chromosomal damage induced hy furocoumarins and UVA in hamster and human cells including cells from patients with ataxia telangiectasia and xeroderma pigmentosum. Mutation Research, 84, 113-124. 

Ataxia telangiectasia is an autosomal recessive disease characterized by neurologic, endocrine, and hepatic abnormalities, as well as a predisposition to malignancy (119). The defect has been traced to a gene on chromosome 11, the ATM gene that codes for a phosphatidylinositol 3-kinase-like protein which is related to the catalytic subunit of DNA-dependent protein kinase. This protein has a role in signal transduction, DNA repair, and control of the cell cycle (120). Affected patients have a defect in cell-mediated immunity. A decrease in semm IgA is seen in a majority of affected patients. IgG2 or total IgG and IgE levels may be decreased, with an increase in IgM. Patients are susceptible to chronic respiratory... 

Ataxia telangiectasia Mutation in gene on chromosome 11, which codes for protein involved in signal transduction, DNA repair, and control of cell cycle. Defect in cell-mediated immunity. Cerebral ataxia and telangiectasias are hallmarks. 

Hartley, K. O., Gell, D., Smith, G. C., et al., DNA-dependent protein kinase catalytic subunit A relative of phosphatidylinositol 3-kinase and the ataxia telangiectasia gene product. Cell 82, 849-856 (1995). 

The ATM protein has been identified as an important member of a reaction chain that leads from detection of DNA damage to activation of the p53 protein. Mutations of the ATM protein are causally associated with the disease ataxia telangiectasia, thus the name ATM (ataxia telangiectasia mutated). The ATM protein has protein kinase activity and is counted as a member of the PI3-kinase family, due to sequence homologies (review Canman et al., 1998). The p53 protein is phosphorylated at Serl5 by ATM kinase (Canman et al., 1998) and it is assumed that this phosphorylation contributes to activation of the p53 protein. The ATM protein is preceded by other protein kinases that are directly or indirectly activated by DNA damage and pass this signal on to the p53 protein via the ATM protein. 

Fanconi s anaemia (homozygotes and heterozygotes), ataxia telangiectasia, xeroderma pigmentosum, normal... 

Association constant. See Formation constant Astacin 627 Asthma 26, 385 Asymmetric unit of crystal 134 Asymmetry of molecules 41-43 handedness 41-43 in oligomers 344 Ataxia telangiectasia 566, 574 Atomic force microscope 131 diagram of 131... 

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