Isolation of the murine branched-chain alpha-ketoacid dehydrogenase E2 subunit promoter region

The promoter region of the murine branched-chain alpha-ketoacid dehydrogenase E2 subunit (dihydrolipoyl transacylase) gene was isolated and characterized. Sequence analysis of the promoter-regulatory region showed the presence of two inverted 'CAAT box' sequences, the most proximal being -42 to -48 bp upstream from the determined transcription initiation site, but no TATA-box sequences, similar to the human BCKAD E2 gene. The boundary of the minimum promoter sequence appeared to reside just inclusive of this first inverted CAAT sequence, but minigene transfer analysis demonstrated that the promoter proximal between -65 and -140 bp is likely to be extremely important for controlling regulated changes in E2 RNA expression. The regulatory effect of this region may be modulated by a number of other upstream regions which were identified within the 7.0 kb sequence examined.