Activin B: precursor sequences, genomic structure and in vitro activities

Mol Endocrinol. 1989 Sep;3(9):1352-8. doi: 10.1210/mend-3-9-1352.


We report here the complete amino acid sequence of the human inhibin beta B-subunit as deduced from the sequence of cDNA and genomic clones. The primary translation product of the beta B mRNA predicts a protein of 407 amino acids, containing a prepro region of 292 amino acids separated by basic amino acids from the mature C-terminal 115 amino acids. Mammalian tissue culture cells transfected with a beta B-subunit expression plasmid secreted an activin B homodimer of approximately 22K mol wt. Coexpression of the beta A- and beta B-subunit mRNAs resulted in the secretion of the three forms of activin, A, AB, and B. Purified activin B was shown to elicit FSH release in an in vitro pituitary assay and trigger the accumulation of hemoglobin in K562 cells. The potency of activin B in both of these assays (ED50 approximately 2 ng/ml) was indistinguishable from that observed for activin A.

MeSH terms

  • Activins*
  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Southern
  • Cell Line
  • Follicle Stimulating Hormone / metabolism
  • Hemoglobins / metabolism
  • Humans
  • In Vitro Techniques
  • Inhibins / genetics*
  • Inhibins / physiology
  • Leukemia, Erythroblastic, Acute / metabolism
  • Macromolecular Substances
  • Molecular Sequence Data
  • Oligopeptides*
  • Peptides / genetics*
  • Polymorphism, Restriction Fragment Length
  • Protein Precursors / genetics
  • Transfection


  • Hemoglobins
  • Macromolecular Substances
  • Oligopeptides
  • Peptides
  • Protein Precursors
  • activin B
  • Activins
  • myelopeptides
  • Inhibins
  • Follicle Stimulating Hormone