Asymmetric expression of transcripts derived from the shared promoter between the divergently oriented ACACA and TADA2L genes

Genomics. 2005 Jan;85(1):71-84. doi: 10.1016/j.ygeno.2004.10.001.


The mammalian gene (ACACA) encoding acetyl-CoA carboxylase-alpha, a key regulatory enzyme of fatty acid synthesis, is transcribed from multiple promoters. We have delineated the 5' boundary of ACACA in four species (human, mouse, rat, and ovine). The 5' end of ACACA is located within a 600- to 700-bp CpG island encompassing a bidirectional promoter shared with the divergently oriented TADA2L, which encodes a component of chromatin-modifying complexes. In mouse and rat, this promoter, now referred to as Acaca PI, is located 43 kb upstream of the previously known regulatory regions. The shared promoter coregulates transcripts for TADA2L and ACACA in an asymmetric fashion in human and mouse tissues. A higher concentration of RNA polymerase II (Pol II) within the intergenic region in brain compared to liver of mouse reflects the greater abundance of the two transcripts in brain. The concentration of Pol II tracking downstream, which is lower than at the promoter, is not significantly different in either gene in the two tissues and does not reflect the 10- and >200-fold greater abundance of Tada2l and Acaca PI transcripts, respectively, in brain. Thus, regulation of clearance of Pol II from the promoter and the rate of elongation may therefore be determinants of the asymmetric expression of these transcripts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetyl-CoA Carboxylase / genetics*
  • Acetyl-CoA Carboxylase / metabolism
  • Animals
  • Base Sequence
  • CpG Islands / genetics
  • DNA-Binding Proteins / genetics*
  • Gene Expression Regulation*
  • Humans
  • Mice
  • Molecular Sequence Data
  • Nuclear Proteins
  • Organ Specificity
  • Promoter Regions, Genetic / genetics*
  • RNA Polymerase II / metabolism
  • Rats
  • Sheep
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription, Genetic


  • DNA-Binding Proteins
  • Nuclear Proteins
  • Tada2a protein, mouse
  • Transcription Factors
  • RNA Polymerase II
  • Acetyl-CoA Carboxylase

Associated data

  • GENBANK/AJ564445
  • GENBANK/AJ564446
  • GENBANK/AJ619664
  • GENBANK/AJ619665