CArG Boxes in the Human Cardiac α -actin Gene are Core Binding Sites for Positive Trans-Acting Regulatory Factors
Abstract
Positively acting, rate-limiting regulatory factors that influence tissue-specific expression of the human cardiac alpha-actin gene in a mouse muscle cell line are shown by in vivo competition and gel mobility-shift assays to bind to upstream regions of its promoter but to neither vector DNA nor a beta-globin promoter. Although the two binding regions are distinctly separated, each corresponds to a cis region required for muscle-specific transcriptional stimulation, and each contains a core CC(A + T-rich)6GG sequence (designated CArG box), which is found in the promoter regions of several muscle-associated genes. Each site has an apparently different binding affinity for trans-acting factors, which may explain the different transcriptional stimulation activities of the two cis regions. Therefore, we conclude that the two CArG box regions are responsible for muscle-specific transcriptional activity of the cardiac alpha-actin gene through a mechanism that involves their binding of a positive trans-acting factor in muscle cells.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- October 1987
- DOI:
- 10.1073/pnas.84.19.6702
- Bibcode:
- 1987PNAS...84.6702M