The Functional Role of the Ataxia Telangiectasia Gene.
Abstract
Ataxia Telangiectasia (A-T) is an autosomal recessive disease characterized by a progressive cerebellar ataxia, severe immune deficiencies, gonadal atrophy, telangiectases, increased risk for cancer, particularly lymphomas, and radiation sensitivity. Additionally, carriers are suspected to be prone to other cancers including breast cancer. We are studying the biochemical function of ATM the product of the gene mutated in A-T in Xenopus, a simple model system suitable for cell cycle studies. We have cloned Xenopus ATM (X-ATM) and raised polyclonal antibodies against recombinant X-ATM that recognize a single polypeptide of 370-kDa in oocytes, embryos, egg extracts and a Xenopus cell line. We found that X-ATM was expressed maternally in eggs and as early as stage II pre-vitellogenic oocytes, and the protein and mRNA were present at relatively constant levels throughout development. Subcellular fractionation showed that the protein was nuclear in both the female and male germlines. The level of X-ATM protein did not change throughout the meiotic divisions or the synchronous mitotic cycles of cleavage stage embryos or following gamma-irradiation of embryos. Finally, we also demonstrated that X-ATM was present in a high molecular weight complex of approximately 500 kDa containing the X-ATM protein and other, as yet unidentified component(s).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1999
- Accession Number
- ADA378155
Entities
People
- Jean Gautier
Organizations
- Columbia University