Cell Fusion pp 135-147 | Cite as

Placenta Trophoblast Fusion

  • Berthold Huppertz
  • Marcus Borges
Part of the Methods in Molecular Biology™ book series (MIMB, volume 475)


It has been known for more than 150 years that syncytial fusion is a normal feature in biological systems. In humans there are two larger syncytial tissues: skeletal muscles fibers and placental syncytiotrophoblast. Other fusion events take place as well from fertilization of the oocyte to infection of human cells by enveloped viruses (however, the latter does not necessarily lead to syncytium formation).

Although knowledge of the fusion process is incomplete, it is clear that membranes do not fuse easily; specific proteins and other factors are required and are selectively activated. In this chapter, we describe the classic proteins, such as the syncytins, assumed to be involved in the fusion process. We also describe other factors that may play roles in the fusion process or in the preparation of the cells to fuse, such as charged phospholipids, divalent cations, and intracellular proteases. Finally, we speculate on why trophoblast cells fuse in vitro and deal with in vitro models of trophoblast fusion and how their fusion rates can be quantified.

Key Words:

Trophoblast; fusion; phospholipid; cation; caspase; calpain; BeWo choriocarcinoma cells; forskolin. 


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Copyright information

© Humana Press, a part of Springer Science + Business Media, LLC 2008

Authors and Affiliations

  • Berthold Huppertz
    • 1
  • Marcus Borges
    • 2
  1. 1.Institute of Cell Biology, Histology and Embryology, Center of Molecular MedicineMedical University of GrazGrazAustria
  2. 2.Department of Obstetrics, Paulista Medicine SchoolUNIFESP-Federal University of São PauloSão PauloBrazil

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