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Isolation of Sertoli Cells and Peritubular Cells from Rat Testes
11:11

Isolation of Sertoli Cells and Peritubular Cells from Rat Testes

Published on: February 8, 2016

Tubulobulbar complexes are intercellular podosome-like structures that internalize intact intercellular junctions

J'Nelle S Young1, Julian A Guttman, Kuljeet S Vaid

  • 1Department of Cellular and Physiological Sciences, Faculty of Medicine, Life Sciences Centre, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.

Biology of Reproduction
|September 19, 2008
PubMed

Insights

Tubulobulbar complexes, actin-rich structures in the testis, internalize intercellular junctions during sperm development. These podosome-like structures are crucial for spermatogenesis and cell adhesion.

Area of Science:

  • Reproductive biology
  • Cell biology
  • Spermatogenesis

Background:

  • Tubulobulbar complexes are actin structures in the mammalian testis.
  • They are involved in intercellular junctions within the seminiferous epithelium.
  • Their role in internalizing junctions during sperm release is hypothesized.

Purpose of the Study:

  • To investigate the molecular composition of apical tubulobulbar complexes.
  • To identify junction molecules present at these structures in rat and mouse testes.
  • To understand the function of tubulobulbar complexes in spermatogenesis.

Main Methods:

  • Immunofluorescence staining of fixed testicular tissue (epithelial fragments and frozen sections).
  • Localization studies of adhesion molecules and cytoskeletal proteins.
  • Analysis of vesicle content within tubulobulbar complexes.

Main Results:

  • Nectin 2 (PVRL2), nectin 3 (PVRL3), and alpha 6 integrin (ITGA6) are found in tubulobulbar complexes.
  • Cortactin (CTTN) is present, supporting their podosome-like nature.
  • Vesicles containing junction molecules are associated with early endosome antigen (EEA1).
  • N-cadherin (CDH2) is localized to desmosomes, not tubulobulbar complexes.

Conclusions:

  • Tubulobulbar complexes are podosome-like structures.
  • They internalize intact intercellular junctions during spermatogenesis.
  • Their molecular composition supports a role in cell adhesion and junction remodeling.

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