Identification of human activin and TGF beta type I receptors that form heteromeric kinase complexes with type II receptors

Cell. 1993 Nov 19;75(4):671-80. doi: 10.1016/0092-8674(93)90488-c.


Transforming growth factor beta (TGF beta) and activin each bind to pairs of membrane proteins, known as receptor types I and II, that associate to form a signaling complex. We report that TSR-I and ActR-I, two human transmembrane serine/threonine kinases distantly related to TGF beta and activin type II receptors, act as type I receptors for these factors. TSR-I is a type I receptor shared by TGF beta and activin, whereas ActR-I is an activin type I receptor. ActR-I, but not TSR-I, signals a particular transcriptional response in concert with activin type II receptors. The results indicate that type I receptors are transmembrane protein kinases that associate with type II receptors to generate diverse heteromeric serine/threonine kinase complexes of different signaling capacities.

Publication types

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

MeSH terms

  • Activin Receptors
  • Activins
  • Cloning, Molecular
  • DNA Primers / chemistry
  • DNA, Complementary / genetics
  • Gene Expression Regulation
  • Humans
  • Inhibins / metabolism*
  • Ligands
  • Macromolecular Substances
  • Molecular Sequence Data
  • Protein Serine-Threonine Kinases / metabolism*
  • RNA, Messenger / genetics
  • Receptors, Cell Surface / metabolism*
  • Receptors, Growth Factor / chemistry
  • Receptors, Growth Factor / metabolism*
  • Receptors, Transforming Growth Factor beta / chemistry
  • Receptors, Transforming Growth Factor beta / metabolism*
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Species Specificity
  • Transforming Growth Factor beta / metabolism*


  • DNA Primers
  • DNA, Complementary
  • Ligands
  • Macromolecular Substances
  • RNA, Messenger
  • Receptors, Cell Surface
  • Receptors, Growth Factor
  • Receptors, Transforming Growth Factor beta
  • Transforming Growth Factor beta
  • Activins
  • Inhibins
  • Protein Serine-Threonine Kinases
  • Activin Receptors

Associated data

  • GENBANK/L17075
  • GENBANK/L20888
  • GENBANK/L20889
  • GENBANK/L22499
  • GENBANK/L26083
  • GENBANK/L33709
  • GENBANK/S60904
  • GENBANK/S60905
  • GENBANK/S60924
  • GENBANK/U00968