Regulation of terminal deoxynucleotidyl transferase gene expression in mice and men.

A nontemplate directed DNA polymerase, terminal deoxynucleotidyl transferase (terminal transferase) is expressed in a tissue-specific and development stage-specific manner. Its enzymatic properties and tissue localization have implicated the protein in development of normal immune function. Significant progress has been made in understanding the enzymology and important domains of this protein. More recently, studies have focused on regulation of the gene that codes for the protein in mice and humans. The murine gene has yielded to these studies more readily than the human gene. A murine basal promoter element has been identified along with several trans-acting protein factors that may regulate gene expression. In the human gene there is no evidence for a basal promoter element. Rather, the promoter exhibits tissue specific properties. The present article reviews recent developments in this field.