title: Isolation of cDNA clones for human adenosine deaminase.
abstract: Clones encoding human adenosine deaminase (ADA) were isolated from a cDNA library made from the lymphoblastoid cell line MOLT-4. The isolation procedure was based on the selection of clones hybridizing with a radioactive probe complementary to an RNA preparation, which had been highly enriched in ADA-specific mRNA. The latter RNA preparation was obtained by size-fractionating MOLT-4 RNA and selecting fractions that were translatable into ADA. The assay for the presence of ADA in the in vitro translation products, was based on immunoprecipitation with a specific anti-ADA serum. The antiserum used was shown to precipitate a 42-kDal protein with the properties of ADA. Positive clones were further screened by means of hybrid-released in vitro translation assays. Two clones were obtained which were able to select mRNA that could be translated into a 42-kDal protein immunoprecipitable with the ADA-antiserum. By use of Southern blots containing DNA from somatic cell hybrids, one of these ADA cDNA clones was assigned to the human chromosome 20 known to contain the ADA gene.
mesh_terms: D000243:Adenosine Deaminase / Q000096:biosynthesis / Q000235:genetics*; D011232:Chemical Precipitation; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification*; D006801:Humans; D007120:Immunochemistry; D009693:Nucleic Acid Hybridization; D009700:Nucleoside Deaminases / Q000235:genetics*; D012313:RNA / Q000302:isolation & purification
chemical_list: D012313:RNA; D004247:DNA; D009700:Nucleoside Deaminases; D000243:Adenosine Deaminase