Cloning and characterization of the 5' part of the high molecular weight transcript of rat DNA polymerase beta.

A rat brain cDNA library has been constructed. Three identical clones of about 2.2 kb representing high molecular weight DNA polymerase beta transcript were found. Sequencing proved our earlier suggestion that both high and low molecular weight DNA polymerase beta transcripts have the same open reading frame and differ mainly at the 3' end. Because of that, alternative polyadenylation is discussed as a possible mechanism for tissue- and development-specific regulation of the DNA polymerase beta gene expression.