Regulation of boar sperm function by the oviduct – formation of a sperm reservoir, modulation of Ca 2+ influx, and release from storage
type: CreativeWork
description: In mammals, an elaborate series of physiological events take place before fertilization of the female gamete. Upon insemination, a small fraction of the sperm deposited in the female reproductive tract is transported to the lower oviduct (isthmus) to form a functional sperm reservoir. The sperm reservoir extends sperm lifespan, prevents polyspermic fertilization, and is implicated in the regulation of capacitation. Once capacitated, a small number of sperm is released from the storage site to form a pool that can bind to the egg. The precise identity of the molecules that mediate the interactions between spermatozoa and epithelial cells of the isthmus are not currently known. Similarly, the molecules and mechanisms involved in the sperm release from the reservoir are poorly understood. It has been proposed, however, that oviduct glycans play a major role in the molecular interaction that leads to the formation of the sperm reservoir. A glycan array previously demonstrated that porcine sperm bound predominantly to motifs containing either biantennary α2,6 sialylated lactosamine (SiLN) or LewisX (LeX) trisaccharide present in the luminal epithelium of the isthmus. Functional data generated by blocking the interaction between uncapacitated sperm and isthmic oviduct cells in vitro strongly suggests that the glycoconjugates containing SiLN and LeX are at least partially involved in the formation of sperm reservoir in swine. These glycans, involved in binding, are also implicated in the regulation of the capacitation process by extending sperm lifespan. Proper calcium ion uptake is a key element for the sperm to acquire hypermotility, which is essential in the final steps of capacitation. Uncapacitated sperm binding to SiLN and LeX reduce intracellular Ca2+ levels under capacitating conditions, which is compatible with the notion that sperm binding to the isthmic epithelium suppresses the normal Ca2+ increase in sperm that occurs during capacitation, thus extending sperm …
abstract: In mammals, an elaborate series of physiological events take place before fertilization of the female gamete. Upon insemination, a small fraction of the sperm deposited in the female reproductive tract is transported to the lower oviduct (isthmus) to form a functional sperm reservoir. The sperm reservoir extends sperm lifespan, prevents polyspermic fertilization, and is implicated in the regulation of capacitation. Once capacitated, a small number of sperm is released from the storage site to form a pool that can bind to the egg. The precise identity of the molecules that mediate the interactions between spermatozoa and epithelial cells of the isthmus are not currently known. Similarly, the molecules and mechanisms involved in the sperm release from the reservoir are poorly understood. It has been proposed, however, that oviduct glycans play a major role in the molecular interaction that leads to the formation of the sperm reservoir. A glycan array previously demonstrated that porcine sperm bound predominantly to motifs containing either biantennary α2,6 sialylated lactosamine (SiLN) or LewisX (LeX) trisaccharide present in the luminal epithelium of the isthmus. Functional data generated by blocking the interaction between uncapacitated sperm and isthmic oviduct cells in vitro strongly suggests that the glycoconjugates containing SiLN and LeX are at least partially involved in the formation of sperm reservoir in swine. These glycans, involved in binding, are also implicated in the regulation of the capacitation process by extending sperm lifespan. Proper calcium ion uptake is a key element for the sperm to acquire hypermotility, which is essential in the final steps of capacitation. Uncapacitated sperm binding to SiLN and LeX reduce intracellular Ca2+ levels under capacitating conditions, which is compatible with the notion that sperm binding to the isthmic epithelium suppresses the normal Ca2+ increase in sperm that occurs during capacitation, thus extending sperm …
author: Machado, Sergio
language: en
keywords: swine, sperm, oviduct, sperm reservoir, glycans, capacitation
date published: 2014-01-16T18:24:57Z
date modified: 2026-07-22T22:25:38Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/46877