CHARACTERIZATION AND REGULATION OF THE NONERYTHROID PORPHOBILINOGEN DEAMINASE PROMOTER

The non-erythroid porphobilinogen deaminase (E.C. 4.3.1.8) promoter wa s investigated according to sequence changes and transcriptional activ ity. The minimal promoter sequence required for maximal transcription, was localized by deletion mapping to -243 to -115 relative to the tra nslational start site. A negative transcriptional element was found be tween -55 and +1, indicating a repression mechanism. A new polymorphis m was identified, at position -235 within the minimal promoter, both i n acute intermittent porphyria patients and healthy control subjects. The polymorphic variants did not affect expression of cloned promoter fragments under the conditions used. (C) 1997 Academic Press.