An alternate promoter directs expression of a truncated, muscle-specific isoform of the human ankyrin 1 gene

J Biol Chem. 1998 Jan 16;273(3):1339-48. doi: 10.1074/jbc.273.3.1339.

Abstract

Ankyrin 1, an erythrocyte membrane protein that links the underlying cytoskeleton to the plasma membrane, is also expressed in brain and muscle. We cloned a truncated, muscle-specific ankyrin 1 cDNA composed of novel 5' sequences and 3' sequences previously identified in the last 3 exons of the human ankyrin 1 erythroid gene. Northern blot analysis revealed expression restricted to cardiac and skeletal muscle tissues. Deduced amino acid sequence of this muscle cDNA predicted a peptide of 155 amino acids in length with a hydrophobic NH2 terminus. Cloning of the corresponding chromosomal gene revealed that the ankyrin 1 muscle transcript is composed of four exons spread over approximately 10 kilobase pairs of DNA. Reverse transcriptase-polymerase chain reaction of skeletal muscle cDNA identified multiple cDNA isoforms created by alternative splicing. The ankyrin 1 muscle promoter was identified as a (G + C)-rich promoter located > 200 kilobase pairs from the ankyrin 1 erythroid promoter. An ankyrin 1 muscle promoter fragment directed high level expression of a reporter gene in cultured C2C12 muscle cells, but not in HeLa or K562 (erythroid) cells. DNA-protein interactions were identified in vitro at a single Sp1 and two E box consensus binding sites contained within the promoter. A MyoD cDNA expression plasmid transactivated an ankyrin 1 muscle promoter fragment/reporter gene plasmid in a dose-dependent fashion in both HeLa and K562 cells. A polyclonal antibody raised to human ankyrin 1 muscle-specific sequences reacted with peptides of 28 and 30 kDa on immunoblots of human skeletal muscle.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alternative Splicing
  • Amino Acid Sequence
  • Ankyrins / genetics*
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary / chemistry
  • DNA, Complementary / isolation & purification
  • Erythroid Precursor Cells / metabolism
  • Exons
  • Gene Expression Regulation*
  • Humans
  • Molecular Sequence Data
  • Muscle, Skeletal / metabolism
  • Muscles / metabolism*
  • MyoD Protein / metabolism
  • Myocardium / metabolism
  • Promoter Regions, Genetic*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Transcriptional Activation

Substances

  • ANK1 protein, human
  • Ankyrins
  • DNA, Complementary
  • MyoD Protein
  • Recombinant Proteins

Associated data

  • GENBANK/AF005213
  • GENBANK/AF005214
  • GENBANK/AF005215