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Updated: May 22, 2026
10:23
Analysis of Epididymal Protein Synthesis and Secretion
Published on: August 25, 2018
Nonpathological extracellular amyloid is present during normal epididymal sperm maturation
Sandra Whelly1, Seethal Johnson, Jonathan Powell
1Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas, USA.
Plos One
|May 10, 2012
Summary
Nonpathological amyloid structures containing cystatin-related epididymal spermatogenic (CRES) protein are found in the mouse epididymis. These extracellular amyloids may play a role in sperm maturation without causing harm.
Area of Science:
- Biochemistry
- Cell Biology
- Reproductive Biology
Background:
- Amyloids, typically linked to neurodegenerative diseases, are protein aggregates with a cross-β-sheet structure.
- Recent findings suggest nonpathological, intracellular amyloids may have biological functions.
- The cystatin-related epididymal spermatogenic (CRES) protein, a protease inhibitor, forms amyloid in vitro.
Purpose of the Study:
- To investigate the in vivo presence and function of CRES amyloid structures in the mouse epididymis.
- To determine if CRES amyloid is extracellular and nonpathological.
- To explore potential roles of CRES amyloid in sperm maturation and the epididymal environment.
Main Methods:
- Immunohistochemical analysis of mouse epididymal tissues.
- Microscopic examination of amyloid structures within the epididymal lumen.
- Assessment of cytotoxic effects on spermatozoa.
Main Results:
- Amyloid structures containing CRES were identified in the normal mouse epididymal lumen.
- These extracellular CRES amyloid structures showed no apparent cytotoxic effects on spermatozoa.
- The morphology of CRES amyloid structures varied along the epididymal tubule.
Conclusions:
- Functional, nonpathological amyloid structures can exist extracellularly, specifically in the epididymis.
- CRES amyloid may contribute to sperm maturation or maintaining the epididymal luminal milieu.
- The presence of extracellular functional amyloids suggests potential roles in other organ systems.
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