A 105- to 94-kilodalton protein in the epididymal fluids of domestic mammals is angiotensin I-converting enzyme (ACE); evidence that sperm are the source of this ACE.
Abstract: SDS-PAGE analysis of luminal fluid from the ram testis and epididymis revealed a protein of about 105 kDa in the fluid in the caput epididymal region. The molecular mass of this fluid protein shifted from 105 kDa to 94 kDa in the distal caput epididymidis and remained at 94 kDa in the lower regions of the epididymis. The possible sperm origin of this protein was suggested by the decrease in intensity of a 105-kDa compound on the sperm plasma membrane extract and by its total disappearance from the fluid of animals with impaired sperm production caused by scrotal heating. The 94-kDa protein was purified from ram cauda epididymal fluid, and a rabbit polyclonal antiserum was obtained. This antiserum showed that membranes of testicular sperm and sperm from the initial caput were positive for the presence of an immunologically related antigen. The protein was immunolocalized mainly on the flagellar intermediate piece, whereas in some corpus and caudal sperm, only the apical ridge of the acrosomal vesicle was labeled. The purified protein was microsequenced: its N-terminal was not found in the sequence database, but its tryptic fragments matched the sequence of the angiotensin I-converting enzyme (ACE). Indeed, the purified 94-kDa protein exhibited a carboxypeptidase activity inhibited by specific blockers of ACE. All the soluble seminal plasma ACE activity in the ram was attributable to the 94-kDa epididymal fluid ACE. The polyclonal antiserum also showed that a soluble form of ACE appeared specifically in the caput epididymal fluid of the boar, stallion, and bull. This soluble form was responsible for all the ACE activity observed in the fluid from the distal caput to the cauda epididymidis in these species. Our results strongly suggest that the epididymal fluid ACE derives from the germinal form of ACE that is liberated from the testicular sperm in a specific epididymal area.
Publication Date: 1999-03-20 PubMed ID: 10084969DOI: 10.1095/biolreprod60.4.937Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The research paper discusses the source of angiotensin I-converting enzyme (ACE) in the epididymal fluids of domestic animals, suggesting that it originates from sperm.
Introduction
- The study investigates where the angiotensin I-converting enzyme (ACE), a protein observed in the epididymal fluids of domestic animals, originates from. The protein was found to be an essential component in the process of sperm production and fertilization.
Methodology
- A technique called SDS-PAGE analysis was performed on the luminal fluid from the ram testis and epididymis to study the protein content.
- The protein of about 105 kDa was found in the fluid at the upper part of the epididymis, but the weight shifted to 94 kDa towards the lower region.
- The team suggested that the protein originated from sperm due to its disappearance in animals with low sperm counts. This was caused by scrotal heating, affecting sperm production.
- The 94-kDa protein was purified from the ram cauda epididymal fluid, and a rabbit polyclonal antiserum was used to test for antigen presence.
- Antigen was found to be positive in both the testicular sperm membranes and the sperm from the upper epididymis.
- The function of ACE was identified by observing carboxypeptidase activity that could be blocked by specific ACE inhibitors.
Findings
- The purified protein was microsequenced, and its tryptic fragments matched the sequence of ACE. This suggests that the protein was an angiotensin I-converting enzyme.
- ACE activity in ram seminal plasma was attributed to the 94-kDa epididymal fluid ACE.
- The same ACE form appeared in the epididymal fluid of boars, stallions, and bulls.
- The presence of ACE in these species was specific for the area from the lower caput to the end of the epididymis.
Conclusion
- The results strongly indicate that the ACE found in epididymal fluid is derived from the germinal form of ACE, specifically liberated from testicular sperm in a precise area within the epididymis.
- These findings contribute to the understanding of sperm and seminal plasma biology in mammals, particularly the role ACE plays in the reproductive system.
Cite This Article
APA
Gatti JL, Druart X, Guérin Y, Dacheux F, Dacheux JL.
(1999).
A 105- to 94-kilodalton protein in the epididymal fluids of domestic mammals is angiotensin I-converting enzyme (ACE); evidence that sperm are the source of this ACE.
Biol Reprod, 60(4), 937-945.
https://doi.org/10.1095/biolreprod60.4.937 Publication
Researcher Affiliations
- URA 1291 INRA-CNRS, Institut National de la Recherche Agronomique, Station de Physiologie de la Reproduction des Mammifères Domestiques, 37380 Monnaie, France.gatti@tours.inra.fr
MeSH Terms
- Amino Acid Sequence
- Animals
- Animals, Domestic
- Body Fluids / enzymology
- Cattle
- Epididymis / enzymology
- Horses
- Male
- Molecular Sequence Data
- Molecular Weight
- Peptide Fragments / chemistry
- Peptidyl-Dipeptidase A / analysis
- Peptidyl-Dipeptidase A / chemistry
- Rabbits
- Semen / enzymology
- Sequence Homology
- Sheep
- Spermatozoa / enzymology
- Swine
Citations
This article has been cited 14 times.- Park YJ, Lee BM, Pang WK, Ryu DY, Rahman MS, Pang MG. Low Sperm Motility Is Determined by Abnormal Protein Modification during Epididymal Maturation.. World J Mens Health 2022 Jul;40(3):526-535.
- Shum W, Zhang BL, Cao AS, Zhou X, Shi SM, Zhang ZY, Gu LY, Shi S. Calcium Homeostasis in the Epididymal Microenvironment: Is Extracellular Calcium a Cofactor for Matrix Gla Protein-Dependent Scavenging Regulated by Vitamins.. Front Cell Dev Biol 2022;10:827940.
- Tumova L, Zigo M, Sutovsky P, Sedmikova M, Postlerova P. Ligands and Receptors Involved in the Sperm-Zona Pellucida Interactions in Mammals.. Cells 2021 Jan 12;10(1).
- Carvajal-Serna M, Fatnassi M, Torres-Ruda F, Cardozo JA, Grajales-Lombana H, Hammadi M, Abecia JA, Muiño-Blanco T, Pérez-Pe R, Cebrián-Pérez JÁ, Casao A. Vasectomy and Photoperiodic Regimen Modify the Protein Profile, Hormonal Content and Antioxidant Enzymes Activity of Ram Seminal Plasma.. Int J Mol Sci 2020 Oct 29;21(21).
- Feng X, Ma BF, Liu B, Ding P, Wei JH, Cheng P, Li SY, Chen DX, Sun ZJ, Li Z. The Involvement of the Chemokine RANTES in Regulating Luminal Acidification in Rat Epididymis.. Front Immunol 2020;11:583274.
- Breton S, Nair AV, Battistone MA. Epithelial dynamics in the epididymis: role in the maturation, protection, and storage of spermatozoa.. Andrology 2019 Sep;7(5):631-643.
- Kerns K, Zigo M, Sutovsky P. Zinc: A Necessary Ion for Mammalian Sperm Fertilization Competency.. Int J Mol Sci 2018 Dec 18;19(12).
- Breton S, Brown D. Regulation of luminal acidification by the V-ATPase.. Physiology (Bethesda) 2013 Sep;28(5):318-29.
- Ijiri TW, Merdiushev T, Cao W, Gerton GL. Identification and validation of mouse sperm proteins correlated with epididymal maturation.. Proteomics 2011 Oct;11(20):4047-62.
- Fàbrega A, Guyonnet B, Dacheux JL, Gatti JL, Puigmulé M, Bonet S, Pinart E. Expression, immunolocalization and processing of fertilins ADAM-1 and ADAM-2 in the boar (Sus domesticus) spermatozoa during epididymal maturation.. Reprod Biol Endocrinol 2011 Jun 30;9:96.
- Shum WW, Ruan YC, Da Silva N, Breton S. Establishment of cell-cell cross talk in the epididymis: control of luminal acidification.. J Androl 2011 Nov-Dec;32(6):576-86.
- Shum WW, Da Silva N, Brown D, Breton S. Regulation of luminal acidification in the male reproductive tract via cell-cell crosstalk.. J Exp Biol 2009 Jun;212(Pt 11):1753-61.
- Shum WW, Da Silva N, McKee M, Smith PJ, Brown D, Breton S. Transepithelial projections from basal cells are luminal sensors in pseudostratified epithelia.. Cell 2008 Dec 12;135(6):1108-17.
- Belleannée C, Da Silva N, Shum WW, Marsolais M, Laprade R, Brown D, Breton S. Segmental expression of the bradykinin type 2 receptor in rat efferent ducts and epididymis and its role in the regulation of aquaporin 9.. Biol Reprod 2009 Jan;80(1):134-43.
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