DNA POLYMERASES-ALPHA AND POLYMERASES-DELTA ARE IMMUNOLOGICALLY AND STRUCTURALLY DISTINCT

  • 5 April 1989
    • journal article
    • research article
    • Vol. 264  (10) , 5924-5928
Abstract
The relationship between DNA polymerases .alpha. and .delta. are evaluated immunologically by monoclonal antibody specifically against DNA polymerase .alpha. and murine polyclonal antiserum against calf thymus DNA polymerase .delta.. DNA polymerases .alpha. and .delta. are found to be immunologically distinct. The structural relationship between the proliferating cell nuclear antigen (PCNA)-dependent calf DNA polymerase .delta. and DNA polymerase .alpha. from human and calf was analyzed by two-dimensional tryptic peptide mapping of the catalytic polypeptides. The results demonstrate that the catalytic polypeptides of the PCNA-dependent calf polymerase .delta. and DNA polymerase .alpha. are distinct, unrelated, and do not share any common structural determinants. The immunological and structural relationship between a recently identified PCNA-independent form of DNA polymerase .delta. from HeLa cells was also assessed. This PCNA-independent human polymerase .delta. was found to be immunologically unrelated to human polymerase .alpha. but to share some immunological and structural determinants with the PCNA-dependent calf thymus polymerase .delta.