The Fur Seal—a Model Lactation Phenotype to Explore Molecular Factors Involved in the Initiation of Apoptosis at Involution

  • Julie A. Sharp
  • Christophe Lefevre
  • Amelia J. Brennan
  • Kevin R. Nicholas


Mammary gland involution requires co-ordination of milk production, immune responses, apoptosis and remodeling. Initiation and progression of each of these components involves integral control by the mammary gland. Although cell-based culture models and genetically manipulated animals have shed light on these processes, the factors controlling each step in the involution cascade are still poorly understood. The fur seal displays a unique lactation phenotype. During the lactation cycle the mammary gland downregulates milk production and initiates an immune response but fails to initiate the apoptotic phase of involution, allowing the female fur seal to undertake long foraging trips of up to 28 days between suckling bouts. Upon return to shore the female continues feeding her pup following resumption of lactation and milk production. Expression profiling of genes involved in this lactation cycle provides valuable tools for investigation of the factors responsible for the initiation of apoptosis at involution.


Fur seal Lactation Local control Mammary gland Involution Acute phase response 



feedback inhibitor of lactation


insulin-like growth factors


matrix metalloproteinase


tissue inhibitors of metalloproteinase


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Julie A. Sharp
    • 1
  • Christophe Lefevre
    • 1
    • 2
  • Amelia J. Brennan
    • 1
  • Kevin R. Nicholas
    • 1
  1. 1.CRC for Innovative Dairy Products, Department of ZoologyUniversity of MelbourneMelbourneAustralia
  2. 2.Victorian Bioinformatics ConsortiumMonash UniversityClayton, MelbourneAustralia

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