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Published on: October 30, 2012

Expression cloning of an activin receptor, a predicted transmembrane serine kinase

L S Mathews1, W W Vale

  • 1Clayton Foundation Laboratories for Peptide Biology, Salk Institute, La Jolla, California 92037.

Cell
|June 14, 1991
PubMed

Insights

Researchers cloned an activin receptor cDNA from mouse pituitary cells. This receptor binds activin A with high affinity and possesses a serine/threonine kinase domain, suggesting a role in cellular signaling pathways.

Area of Science:

  • Molecular Biology
  • Cellular Signaling
  • Endocrinology

Background:

  • Activins regulate diverse biological processes, including development and pituitary function.
  • Understanding the cellular mechanisms of activin action requires identification of its receptors.

Purpose of the Study:

  • To clone and characterize the cDNA encoding an activin receptor from AtT20 mouse corticotropic cells.
  • To investigate the binding properties and structural features of the identified activin receptor.

Main Methods:

  • Screening of COS cell transfectants for 125I-activin A binding.
  • Cloning of cDNAs encoding the activin receptor.
  • Affinity binding assays and competition studies.

Main Results:

  • cDNAs coding for a 494-amino acid activin receptor were isolated.
  • The receptor features an extracellular ligand-binding domain, a transmembrane domain, and an intracellular serine/threonine kinase domain.
  • 125I-activin A bound with high affinity (180 pM) and was competed by activin A, activin B, and inhibin A, but not TGF-β1.

Conclusions:

  • A novel activin receptor with kinase activity has been identified in mouse corticotropic cells.
  • The receptor's kinase domain shows homology to the C. elegans daf-1 gene product, suggesting conserved signaling pathways.
  • This finding provides insights into the molecular mechanisms of activin-mediated cellular regulation.

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