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An autocrine axis in the testis that coordinates spermiation and blood-testis barrier restructuring during spermatogenesis
- Source :
- Proceedings of the National Academy of Sciences of the United States of America. 105(26)
- Publication Year :
- 2008
-
Abstract
- The mechanism(s) that regulate and coordinate the events of spermiation and blood-testis barrier (BTB) restructuring in the seminiferous epithelium that occur concurrently at stage VIII of the seminiferous epithelial cycle of spermatogenesis are unknown. In this report, fragments derived from the laminin complex composed of laminin α3, β3, and γ3 chains (laminin-333) at the apical ectoplasmic specialization (apical ES) were shown to modulate BTB dynamics directly and/or indirectly via hemidesmosome. Experiments were performed using cultured Sertoli cells with functional tight junction (TJ) barrier and the ultrastructural features of the BTB but not apical ES. Recombinant protein fragments of laminin β3 and γ3 chains were shown to reduce the protein levels of occludin and β1-integrin dose dependently at the Sertoli-Sertoli and Sertoli-basement membrane interface, respectively, thereby destabilizing the BTB permeability function. These results were corroborated by transient overexpression of laminin fragments in Sertoli cells. To further assess the role of β1-integrin in hemidesmosome, knockdown of β1-integrin in Sertoli cells by RNAi was found to associate with occludin redistribution at the Sertoli-Sertoli cell interface, wherein occludin moved away from the cell surface and became associated with endosomes, thereby destabilizing the BTB. In short, an apical ES-BTB-hemidesmosome autocrine regulatory axis was identified in testes, coordinating the events of spermiation and BTB restructuring that occur at the opposite ends of the seminiferous epithelium during spermatogenesis. © 2008 by The National Academy of Sciences of the USA.<br />link_to_OA_fulltext
- Subjects :
- Male
endocrine system
Ectoplasmic specialization
Biology
Occludin
Models, Biological
Tight Junctions
Rats, Sprague-Dawley
medicine
Animals
Hemidesmosome
Anchoring junction
Laminin complex
Spermatogenesis
Tight junction
Blood-Testis Barrier
Cells, Cultured
Blood–testis barrier
Multidisciplinary
Basal ectoplasmic specialization
Sertoli Cells
urogenital system
Integrin beta1
Membrane Proteins
Apical ectoplasmic specialization
Biological Sciences
Sertoli cell
Peptide Fragments
Cell biology
Rats
Autocrine Communication
Protein Transport
medicine.anatomical_structure
Seminiferous Epithelium
Microscopy, Fluorescence
Adjudin
RNA Interference
Laminin
Subjects
Details
- ISSN :
- 10916490
- Volume :
- 105
- Issue :
- 26
- Database :
- OpenAIRE
- Journal :
- Proceedings of the National Academy of Sciences of the United States of America
- Accession number :
- edsair.doi.dedup.....03fdd09d13bceae358d2a135eea86261