The Testis pp 151-160 | Cite as

The Actin-Bundling Protein Espin and Its Role in the Ectoplasmic Specialization

  • James R. Bartles
  • Lili Zheng
  • Min Wang
  • Bin Chen
Conference paper
Part of the Serono Symposia USA book series (SERONOSYMP)


The ectoplasmic specialization is thought to anchor and position spermatids within the seminiferous epithelium throughout much of spermiogenesis. It may also contribute to the “blood—testis” barrier between Sertoli cells (1,2). These activities are believed to depend critically on the ectoplasmic specialization junctional plaque, which is characterized by a layer of parallel actin bundles sandwiched between the Sertoli-cell plasma membrane and a cistern of endoplasmic reticulum (1,2). The parallel actin bundles are believed to act both as a scaffold that supports and stabilizes an adhesive domain within the overlying Sertoli-cell plasma membrane and indirectly, via the cistern of endoplasmic reticulum, as a link to an underlying network of microtubules to allow for changes in the position of the ectoplasmic specialization—spermatid complex (1,2).


Actin Filament Sertoli Cell Brush Border Seminiferous Epithelium Actin Bundle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag New York, Inc. 2000

Authors and Affiliations

  • James R. Bartles
  • Lili Zheng
  • Min Wang
  • Bin Chen

There are no affiliations available

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