Neurosecretion pp 107-112 | Cite as

The Role of Head Activator in Cell Growth and Control Processes

  • Graeme Bilbe
  • H. Chica Schaller


Head activator (HA) is a neuropeptide isolated and sequenced from Hydra, a freshwater coelenterate. It is an undecapeptide of molecular weight 1124 and has the sequence p-Glu-Pro-Pro-Gly-Gly-Ser-Lys-Val-Ile-Leu-Phe (Schaller and Bodenmuller, 1981). In Hydra where its active concentration is 10-13M, HA acts as a head-specific growth and differentiation factor (Schaller, 1973).


Head Activator Thymidine Labelling Index Hydra Peptide Teratoma Cell Morphogentic Peptide 


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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • Graeme Bilbe
    • 1
  • H. Chica Schaller
    • 1
  1. 1.Zentrum für Molekulare Biologie HeidelbergHeidelbergGermany

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