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Yi S, Feng Y, Wang Y, Ma F. Sialylation: fate decision of mammalian sperm development, fertilization, and male fertility†. Biol Reprod 2023; 109:137-155. [PMID: 37379321 DOI: 10.1093/biolre/ioad067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/14/2023] [Accepted: 06/19/2023] [Indexed: 06/30/2023] Open
Abstract
Sperm development, maturation, and successful fertilization within the female reproductive tract are intricate and orderly processes that involve protein translation and post-translational modifications. Among these modifications, sialylation plays a crucial role. Any disruptions occurring throughout the sperm's life cycle can result in male infertility, yet our current understanding of this process remains limited. Conventional semen analysis often fails to diagnose some infertility cases associated with sperm sialylation, emphasizing the need to comprehend and investigate the characteristics of sperm sialylation. This review reanalyzes the significance of sialylation in sperm development and fertilization and evaluates the impact of sialylation damage on male fertility under pathological conditions. Sialylation serves a vital role in the life journey of sperm, providing a negatively charged glycocalyx and enriching the molecular structure of the sperm surface, which is beneficial to sperm reversible recognition and immune interaction. These characteristics are particularly crucial during sperm maturation and fertilization within the female reproductive tract. Moreover, enhancing the understanding of the mechanism underlying sperm sialylation can promote the development of relevant clinical indicators for infertility detection and treatment.
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Affiliation(s)
- Shiqi Yi
- Center for Translational Medicine, Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
- Department of Obstetrics and Gynecology, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Ying Feng
- West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Yan Wang
- Department of Obstetrics and Gynecology, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Fang Ma
- Center for Translational Medicine, Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
- Department of Obstetrics and Gynecology, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China
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Cai W, Chen W, Wang Y, Bu X, Xia X, Nie L. Sperm storage in the oviduct of the Chinese pond turtle Mauremys reevesii depends on oestrogen-based suppression of the TLR2/4 immune pathway. Reprod Fertil Dev 2021; 33:736-745. [PMID: 34602123 DOI: 10.1071/rd20341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 07/08/2021] [Indexed: 11/23/2022] Open
Abstract
The long-term storage of spermatozoa in the female reproductive tract is limited by the innate immune system. Oestrogen plays a role in regulating the innate immune system. Thus, exploring the expression of genes in the Toll-like receptor (TLR) 2/4 pathway and oestrogen receptors in the oviduct of Mauremys reevesii could contribute to our understanding of the mechanism of sperm storage. In this study, three parts of the oviduct (isthmus, uterus and vagina) in three mated and unmated female turtles were used to perform immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR). Immunohistochemistry revealed that the TLR2/4 protein was mainly distributed in epithelial tissues and glandular cell membranes, and that TLR2/4 levels in the oviduct were significantly decreased in mated compared with unmated turtles. Real-time qPCR indicated that TLR2/4, myeloid differentiation factor 88 (MyD88), interleukin 1 receptor associated kinase 4 (IRAK4), TNF receptor associated factor 6 (TRAF6), interferon regulatory factor 3 (IRF3) and interleukin 6 (IL6) mRNA expression was significantly higher in the oviduct of unmated than mated turtles, whereas the opposite was true for the expression of oestrogen receptor 1 (ESR1) and progesterone receptor (PGR). These results indicate that when spermatozoa are stored in the oviduct, an increase in oestrogen suppresses the immune response induced by the TLR2/4 pathway so that spermatozoa are not removed as a foreign substance, but stored until fertilisation. The findings of this study are relevant to our understanding of the relationship between sperm storage and the innate immune system in the oviduct of reptiles.
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Affiliation(s)
- Wenlong Cai
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Wei Chen
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Yajie Wang
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Xingjiang Bu
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China; and Corresponding author.
| | - Xingquan Xia
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Liuwang Nie
- Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
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Yu L, Zheng Y, Feng Y, Ma F. Role of L-selectin on leukocytes in the binding of sialic acids on sperm surface during the phagocytosis of sperm in female reproductive tract. Med Hypotheses 2018; 120:4-6. [DOI: 10.1016/j.mehy.2018.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/07/2018] [Indexed: 01/06/2023]
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Sakkas D, Ramalingam M, Garrido N, Barratt CLR. Sperm selection in natural conception: what can we learn from Mother Nature to improve assisted reproduction outcomes? Hum Reprod Update 2015; 21:711-26. [PMID: 26386468 PMCID: PMC4594619 DOI: 10.1093/humupd/dmv042] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 08/12/2015] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND In natural conception only a few sperm cells reach the ampulla or the site of fertilization. This population is a selected group of cells since only motile cells can pass through cervical mucus and gain initial entry into the female reproductive tract. In animals, some studies indicate that the sperm selected by the reproductive tract and recovered from the uterus and the oviducts have higher fertilization rates but this is not a universal finding. Some species show less discrimination in sperm selection and abnormal sperm do arrive at the oviduct. In contrast, assisted reproductive technologies (ART) utilize a more random sperm population. In this review we contrast the journey of the spermatozoon in vivo and in vitro and discuss this in the context of developing new sperm preparation and selection techniques for ART. METHODS A review of the literature examining characteristics of the spermatozoa selected in vivo is compared with recent developments in in vitro selection and preparation methods. Contrasts and similarities are presented. RESULTS AND CONCLUSIONS New technologies are being developed to aid in the diagnosis, preparation and selection of spermatozoa in ART. To date progress has been frustrating and these methods have provided variable benefits in improving outcomes after ART. It is more likely that examining the mechanisms enforced by nature will provide valuable information in regard to sperm selection and preparation techniques in vitro. Identifying the properties of those spermatozoa which do reach the oviduct will also be important for the development of more effective tests of semen quality. In this review we examine the value of sperm selection to see how much guidance for ART can be gleaned from the natural selection processes in vivo.
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Affiliation(s)
- Denny Sakkas
- Boston IVF, 130 Second Ave, Waltham, MA 02451, USA
| | - Mythili Ramalingam
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD19SY, UK
| | | | - Christopher L R Barratt
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD19SY, UK
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5
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Abstract
During maturation, the surface of mammalian spermatozoa undergoes dramatic changes leading to the acquisition of properties vital for survival and performance in the female reproductive tract. A prominent change is the addition to the sperm surface of an atypical β-defensin polypeptide. In primates, the β-defensin DEFB126 becomes adsorbed to the entire sperm surface as spermatozoa move through the epididymal duct. DEFB126 has a conserved β-defensin core and a unique long glycosylated peptide tail. The carbohydrates of this domain contribute substantially to the sperm glycocalyx. DEFB126 is critical for efficient transport of sperm in the female reproductive tract, preventing their recognition by the female immune system, and might facilitate the delivery of capacitated sperm to the site of fertilization. A newly discovered dinucleotide deletion in the human DEFB126 gene is unusually common in diverse populations and results in a null allele. Predictably, men who are homozygous for the deletion produce sperm with an altered glycocalyx and impaired function, and have reduced fertility. Insights into the biology of DEFB126 are contributing to a better understanding of reproductive fitness in humans, as well as the development of diagnostics and therapeutics for male infertility.
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Radhakrishnan P, Fedorka KM. Influence of female age, sperm senescence and multiple mating on sperm viability in female Drosophila melanogaster. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:778-783. [PMID: 21419131 DOI: 10.1016/j.jinsphys.2011.02.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Revised: 02/23/2011] [Accepted: 02/25/2011] [Indexed: 05/30/2023]
Abstract
Sperm viability has been associated with the degree of promiscuity across species, as well as the degree of reproductive success within species. Thus, sperm survival within the female reproductive tract likely plays a key role in how mating systems evolve. In the fruit fly, Drosophila melanogaster, however, the extent and cause of sperm death has been the subject of recent debate. Here, we assess sperm death within the female reproductive tract of D. melanogaster following single and multiple matings in order to elucidate the extent of death and its potential mechanisms, including an acute female response to mating, female age and/or sperm senescence. We found no evidence that sperm viability was influenced by an acute female response or female age. We also found that rival ejaculates did not influence viability, supporting recent work in the system. Instead, the majority of death appears to be due to the aging of male gametes within the female, and that at least some dead resident sperm remain in the female after multiple mating. In contrast to earlier in vivo work, we found that overall sperm death was minimal (8.7%), indicating viability should have a negligible influence on female remating rates.
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Affiliation(s)
- Preethi Radhakrishnan
- Department of Natural Sciences, LaGuardia Community College, Long Island City, NY 11101, USA.
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CASTELLA G, CHRISTE P, CHAPUISAT M. Mating triggers dynamic immune regulations in wood ant queens. J Evol Biol 2009; 22:564-70. [DOI: 10.1111/j.1420-9101.2008.01664.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Reinhardt K. Evolutionary Consequences of Sperm Cell Aging. QUARTERLY REVIEW OF BIOLOGY 2007; 82:375-93. [DOI: 10.1086/522811] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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9
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Fedorka KM, Linder JE, Winterhalter W, Promislow D. Post-mating disparity between potential and realized immune response in Drosophila melanogaster. Proc Biol Sci 2007; 274:1211-7. [PMID: 17311779 PMCID: PMC2189566 DOI: 10.1098/rspb.2006.0394] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Reproductive costs are an essential component of evolutionary theory. For instance, an increase in reproduction is generally coupled with a decrease in immunocompetence shortly after mating. However, recent work in Drosophila melanogaster suggests that the potential to mount an immune response, as measured by the levels of immune gene expression, increases after mating. These data are in contrast to previous studies, which suggest that mating can reduce a fly's ability to survive an actual bacterial challenge (realized immunity). This pattern may be driven by some aspect of mating, independent of resource limitation, which reduces immune function by inhibiting the effective deployment of immune gene products. Though several studies have examined both the potential and the realized immunity after mating, none have examined these immune measures simultaneously. Here, we examined the link between the potential and the realized immunity in a sterile mutant of D. melanogaster. Shortly after mating, we found that female immune gene expression was high, but survival against infection was low. Surprisingly, this pattern was reversed within 24 h. Thus, estimates of immunity based on gene expression do not appear to reflect an actual ability to defend against pathogens in the hours following copulation. We discuss the possible mechanisms that may account for this pattern.
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Affiliation(s)
- Kenneth M Fedorka
- Department of Biology, University of Central Florida, Orlando, FL 32816, USA.
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10
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Abstract
Sperm competition and cryptic female choice profoundly affect sperm morphology, producing diversity within both species and individuals. One type of within-individual sperm variation is sperm heteromorphism, in which each male produces two or more distinct types of sperm simultaneously, only one of which is typically fertile (the "eusperm"). The adaptive significance of nonfertile "parasperm" types is poorly understood, although numerous sperm-heteromorphic species are known from many disparate taxa. This paper examines in detail two female-centred hypotheses for the evolution and maintenance of this unconventional sperm production strategy. First, we use game theoretical models to establish that parasperm may function to protect eusperm from female-generated spermicide, and to elucidate the predictions of this idea. Second, we expand on the relatively undeveloped idea that parasperm are used by females as a criterion for cryptic female choice, and discuss the predictions generated by this idea compared to other hypotheses proposed to explain sperm heteromorphism. We critically evaluate both hypotheses, suggest ways in which they could be tested, and propose taxa in which they could be important.
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Affiliation(s)
- L Holman
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
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Abstract
In many animal systems, females exhibit a localized immune response to insemination that helps defend against sexually transmitted disease. However, this response may also kill sperm, reducing a male's reproductive potential. If males could suppress this response, they may be able to increase their sperm's representation in the female's reproductive tract, thereby increasing their fitness. Here we address the hypothesis that, under conditions of sperm competition, males interfere with female immunity. To test our hypothesis, we manipulated levels of female mating frequency (single vs. multiply mated) and seminal diversity (monandrous vs. polyandrous) in the cricket, Allonemobius socius and measured female immune response. As mating frequency increased, female hemocyte load decreased, indicating a general reproductive cost. As seminal diversity increased, phenoloxidase (PO) activity (in vitro measure of 'potential' macroparasitic defense) increased and encapsulation ability (in vivo measure of 'realized' macroparasitic defense) decreased in polyandrous females. These results suggest that males may manipulate female immunity by interrupting the pro-PO cascade, which begins with the activation of PO and ends in the encapsulation of invading foreign bodies. In other words, female immune function may serve as a battleground over which a sexual conflict is fought.
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Affiliation(s)
- Kenneth M Fedorka
- Department of Biology, University of California Riverside, Riverside, CA, USA.
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Kunz G, Beil D, Huppert P, Leyendecker G. Control and function of uterine peristalsis during the human luteal phase. Reprod Biomed Online 2006; 13:528-40. [PMID: 17007674 DOI: 10.1016/s1472-6483(10)60641-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rhythmic peristaltic contractions of the muscular wall of the non-pregnant uterus can be demonstrated throughout the menstrual cycle, with a maximum just before ovulation. However, not only during the follicular phase but also during the luteal phase, the uterus shows remarkable contractile activity. The present study was conducted in order to examine uterine peristaltic activity and its function during the luteal phases of the human menstrual cycle. The results of vaginal sonography of uterine peristalsis, of hysterosalpingoscintigraphy and of the documentation of the sites of embryo implantation in natural and artificial cycles have shown that uterine peristalsis during the luteal phase is controlled by systemic and probably even more by local hormonal secretion from the fresh corpus luteum, and facilitates the fundal implantation of the blastocyst predominantly ipsilateral to the site of the dominant ovarian structure. Furthermore, this study suggests that the defence against the infiltration and inflammation of the upper genital tract, and thus the degradation of the implanted embryo, represents a further and phylogenetically old and genuine function of the archimetra, which in placentalia was modified in order to participate in the control of invasion of the endometrium by the trophoblast.
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Affiliation(s)
- G Kunz
- Department of Obstetrics and Gynaecology, St Johannes Hospital Dortmund, Dortmund, and Department of Obstetrics and Gynaecology, Academic Teaching Hospital to the University of Frankfurt, Darmstadt, Germany.
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Yudin AI, Generao SE, Tollner TL, Treece CA, Overstreet JW, Cherr GN. Beta-defensin 126 on the cell surface protects sperm from immunorecognition and binding of anti-sperm antibodies. Biol Reprod 2005; 73:1243-52. [PMID: 16079310 DOI: 10.1095/biolreprod.105.042432] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Beta-defensin 126 (DEFB126), formerly known as epididymal secretory protein 13.2 (ESP13.2), coats the entire primate sperm surface until completion of capacitation, and it is a candidate for providing immune protection in the female reproductive tract. To further examine the potential role of DEFB126 as a means of protection from immune recognition, cynomolgus macaque sperm were exposed to a number of treatments that are known to alter sperm surface coats, including capacitation. We used a novel in vivo assay to determine immune recognition: aldehyde-fixed whole sperm injections into rabbits. Following booster injections, immunoblot analyses of whole sperm prepared in various manners was conducted. On Days 60 and 80 post-initial immunization, the antisera showed a remarkably strong reaction to a single 34-36 kDa protein, which was shown to be DEFB126. Sera from rabbits that were immunized with sperm washed more rigorously using Percoll gradients showed an increase in the number and intensity of proteins recognized on whole sperm Western blots, although DEFB126 was still the major immune response. When capacitated sperm, from which most DEFB126 had been released, were used as the immunogen, there was a dramatic increase in the immune recognition to a variety of protein bands. Sperm treated with neuraminidase to remove sialic acid on DEFB126 before fixation were shown to still possess DEFB126, but lacked the sialic acid component of the glycoprotein. These sperm were as immunogenic as capacitated sperm even though the desialylated DEFB126 still covered the entire cell surface. These sperm lost their highly negative charge (the isoelectric point of DEFB126 shifted from pI 3.0 to pI 6.4). Experiments using different sperm plasma membrane protein-specific Igs showed that recognition did not occur when DEFB126 was present, but following capacitation these Igs readily recognized the exposed sperm membrane. Our data suggest that DEFB126 protects the entire primate sperm surface from immune recognition and that the sialic acid moieties are responsible for the cloaking characteristic of this unique glycoprotein.
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Affiliation(s)
- Ashley I Yudin
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, Bodega Marine Laboratory, University of California, Davis, California 94923, USA
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Tollner TL, Yudin AI, Treece CA, Overstreet JW, Cherr GN. Macaque sperm release ESP13.2 and PSP94 during capacitation: the absence of ESP13.2 is linked to sperm-zona recognition and binding. Mol Reprod Dev 2005; 69:325-37. [PMID: 15349845 DOI: 10.1002/mrd.20132] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
ESP13.2 coats the entire surface of macaque sperm and remains until sperm become capacitated (Yudin et al., 2003: Biol Reprod 69: 1118-1128). Capacitation of macaque sperm is synchronized by treatment with dibutyrl cAMP (dbcAMP) and caffeine. ESP13.2 and PSP94 constituted approximately 95% of the proteins released from the sperm surface following treatment with caffeine + dbcAMP. Caffeine and dbcAMP alone induce different patterns of ESP13.2 release. As determined by ELISAs of supernatants and immuno-fluorescent labeling of sperm heads, caffeine alone and caffeine + dbcAMP induced comparable release of ESP13.2, while dbcAMP-treated sperm did not differ from controls. Sperm treated with caffeine + dbcAMP showed a reduction of ESP13.2 from the entire surface, while caffeine treatment alone induced removal of ESP13.2 from the sperm head and midpiece. As confirmed with immunofluorescence, ESP13.2 could be added back to the surfaces of sperm that had been previously exposed to caffeine. Treatment with caffeine significantly increased the number of sperm that bound tightly to the zona pellucida as compared with controls (42 +/- 9 and 13 +/- 3 sperm/zona, respectively; P < or = 0.01). This increase in binding was inhibited by "adding back" ESP13.2 to the sperm surface (12.8 +/- 3; P < or = 0.01). Alexa-conjugated anti-ESP13.2 Ig labeling of live sperm showed that only sperm lacking ESP13.2 over the head were capable of tight binding to the zona. Our results suggest that ESP13.2 masks zona pellucida ligands on the sperm surface and its release, as part of capacitation, is required for sperm-zona interaction.
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Affiliation(s)
- Theodore L Tollner
- Division of Reproductive Biology, Department of Obstetrics and Gynecology, University of California, Davis, California, USA
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Fedorka KM, Zuk M, Mousseau TA. IMMUNE SUPPRESSION AND THE COST OF REPRODUCTION IN THE GROUND CRICKET, ALLONEMOBIUS SOCIUS. Evolution 2004; 58:2478-85. [PMID: 15612291 DOI: 10.1111/j.0014-3820.2004.tb00877.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
One of the most common life history trade-offs in animals is the reduction in survivorship with increasing reproductive effort. Despite the prevalence of this pattern, its underlying physiological mechanisms are not well understood. Here we test the hypothesis that immune suppression mediates this phenotypic trade-off by manipulating reproductive effort and measuring immune function and mortality rates in the striped ground cricket, Allonemobius socius. Because A. socius males provide females with a hemolymph-based nuptial gift during copulation, and many structural components of immunity reside in the hemolymph, we also predicted that sexual selection may differentially affect how disease resistance evolves in males and females. We found that an increased mating effort resulted in a reduced immune ability, coupled with an increased rate in age-specific mortality for both sexes. Thus, immune suppression appears to be a link between reproductive effort and cost in this system. In addition, males and females appeared to differentially invest in several aspects of immunity prior to mating, with males exhibiting a higher concentration of circulating hemocytes and a superior bacterial defense capability. This pattern may be the result of previously established positive selection on gift size due to its affect on female fecundity. In short, female choice for larger gifts may lead to a sexually dimorphic immune ability.
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Affiliation(s)
- Kenneth M Fedorka
- Department of Biology, University of California Riverside, Riverside, California 92521, USA.
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Fedorka KM, Zuk M, Mousseau TA. IMMUNE SUPPRESSION AND THE COST OF REPRODUCTION IN THE GROUND CRICKET, ALLONEMOBIUS SOCIUS. Evolution 2004. [DOI: 10.1554/04-399] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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