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Near-anoxia induces immobilization and sustains viability of sperm stored in ant queens. Sci Rep 2023; 13:3029. [PMID: 36859427 PMCID: PMC9977914 DOI: 10.1038/s41598-023-29705-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/09/2023] [Indexed: 03/03/2023] Open
Abstract
After copulation, insect females store sperm in a spermatheca for some duration until fertilization. At the beginning of their adult lives, ant queens can preserve numerous viable sperm cells from copulation for over ten years. However, the key factors influencing long-term sperm storage have not been identified. Here we show that the spermathecal environment is nearly anoxic, which induces sperm immobilization. Furthermore, mitochondrial respiratory inhibitors suppress sperm motility, suggesting that sperm immobilization may be caused by a shortage of ATP generated from only glycolysis under near-anoxic conditions. Sperm immobilization is not induced by acidification via glycolytic metabolism because the spermathecal fluid is not acidic. Finally, we show that artificial anoxic conditions rather than aerobic conditions sustain viable sperm cells. Therefore, near-anoxia is a key factor influencing long-term sperm storage in ant queens. The viability of sperm cells under artificial anoxia, however, is lower than that of those dissected immediately from queens. Moreover, the immotile sperm cells under more than 4 h of anoxia do not begin swimming after aerobic exposure, unlike those under anoxic conditions for less than 2 h. This finding indicates that factors other than anoxia are also necessary for long-term sperm preservation.
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Shankar G, Gagan TA, Kumari TRS, Marathe GK. Sperm storage by females across the animal phyla: A survey on the occurrence and biomolecules involved in sperm storage. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2022; 340:283-297. [PMID: 36581603 DOI: 10.1002/jez.b.23189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/10/2022] [Accepted: 12/13/2022] [Indexed: 12/31/2022]
Abstract
Long-term sperm storage by females in various regions of the oviduct is documented across many invertebrate and vertebrate species. Although, many reports emphasize on the histology, histochemistry and ultrastructural features of sperm storage, very little is known about the mechanisms underlying the sperm storage. The current review documents the occurrence of sperm storage by females in a wide array of invertebrate and vertebrate species. This review also provides an insight on the presence of various molecular factors of the sperm storage tubules presumably responsible for the prolonged sperm storage with an emphasis on a model reptile, the Indian garden lizard, Calotes versicolor which contains a unique approximately 55-kDa protein in its utero-vaginal lavage and found to inhibit washed epididymal sperm motility in a concentration and time-dependent manner in a reversible fashion.
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Affiliation(s)
- Goutham Shankar
- Department of Studies in Biochemistry, University of Mysore, Mysore, Karnataka, India
| | - Thumbala A Gagan
- Department of Studies in Biochemistry, University of Mysore, Mysore, Karnataka, India.,Department of Zoology, St. Philomena's College, Bannimantap, Mysore, Karnataka, India
| | - Titus R S Kumari
- Department of Zoology, St. Philomena's College, Bannimantap, Mysore, Karnataka, India
| | - Gopal K Marathe
- Department of Studies in Biochemistry, University of Mysore, Mysore, Karnataka, India.,Department of Studies in Molecular Biology, University of Mysore, Mysore, Karnataka, India
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Competitive Sperm-Marked Beetles for Monitoring Approaches in Genetic Biocontrol and Studies in Reproductive Biology. Int J Mol Sci 2022; 23:ijms232012594. [DOI: 10.3390/ijms232012594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/03/2022] [Accepted: 10/12/2022] [Indexed: 11/16/2022] Open
Abstract
Sperm marking provides a key tool for reproductive biology studies, but it also represents a valuable monitoring tool for genetic pest control strategies such as the sterile insect technique. Sperm-marked lines can be generated by introducing transgenes that mediate the expression of fluorescent proteins during spermatogenesis. The homozygous lines established by transgenesis approaches are going through a genetic bottleneck that can lead to reduced fitness. Transgenic SIT approaches have mostly focused on Dipteran and Lepidopteran pests so far. With this study, we provide sperm-marked lines for the Coleopteran pest model organism, the red flour beetle Tribolium castaneum, based on the β2-tubulin promoter/enhancer driving red (DsRed) or green (EGFP) fluorescence. The obtained lines are reasonably competitive and were thus used for our studies on reproductive biology, confirming the phenomenon of ‘last-male sperm precedence’ and that the spermathecae are deployed for long-term sperm storage, enabling the use of sperm from first mating events even after secondary mating events for a long period of time. The homozygosity and competitiveness of the lines will enable future studies to analyze the controlled process of sperm movement into the long-term storage organ as part of a post-mating cryptic female choice mechanism of this extremely promiscuous species.
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Matsumura Y, Gürke S, Tramsen HT, Gorb SN. 3D printed spermathecae as experimental models to understand sperm dynamics in leaf beetles. BMC ZOOL 2020. [DOI: 10.1186/s40850-020-00058-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Postcopulatory mate choice occurs ubiquitously in the animal kingdom. However, it is usually a major challenge to visualise the process taking place in a body. This fact makes it difficult to understand the mechanisms of the process. By focusing on the shape of female sperm storage organs (spermathecae), we aimed to elucidate their functional morphology using six representative beetle species and to simulate sperm dynamics in artificial spermathecae with different structural features.
Results
Morphology and material gradients were studied using micro-computed tomography (μCT) and confocal laser scanning microscopy. This study shows a diversity of external and internal structures of the spermathecae among species. Despite the diversity, all species possess a common pumping region, which is composed of a sclerotised chamber, muscles and a resilin-enriched region. By focusing on the species Agelastica alni, whose spermatheca is relatively simple in shape with an internal protuberance, we simulated sperm dynamics by establishing a fabrication method to create enlarged, transparent, flexible and low-cost 3D models of biological structures based on μCT data. This experiment shows that the internal protuberance in the species functions as an efficient mixing device of stored sperm.
Conclusions
The observed spermathecal musculature implies that the sclerotised chamber of the spermatheca with muscles works as a pumping organ. Our fluid dynamics tests based on 3D printed spermathecae show that a tiny structural difference causes entirely different fluid dynamics in the spermatheca models. This result suggests that structural variations of the spermatheca strongly affect sperm dynamics. However, fluid dynamics tests still require essential measurements including sperm viscosity and the velocity of pumping cycles of the spermatheca.
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Abdelli M, Benbellil-Tafoughalt S, Koene JM. Intra-specific morphological variation of the spermatheca in the simultaneously hermaphroditic land snail Helix aperta. ZOOMORPHOLOGY 2017. [DOI: 10.1007/s00435-017-0379-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pitnick S, Marrow T, Spicer GS. EVOLUTION OF MULTIPLE KINDS OF FEMALE SPERM-STORAGE ORGANS IN DROSOPHILA. Evolution 2017; 53:1804-1822. [PMID: 28565462 DOI: 10.1111/j.1558-5646.1999.tb04564.x] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/1998] [Accepted: 06/02/1999] [Indexed: 11/27/2022]
Abstract
Females of all species belonging to the family Drosophilidae have two kinds of sperm-storage organs: paired spherical spermathecae and a single elongate tubular seminal receptacle. We examined 113 species belonging to the genus Drosophila and closely allied genera and describe variation in female sperm-storage organ use and morphology. The macroevolutionary pattern of organ dysfunction and morphological divergence suggests that ancestrally both kinds of organs stored sperm. Loss of use of the spermathecae has evolved at least 13 times; evolutionary regain of spermathecal function has rarely if ever occurred. Loss of use of the seminal receptacle has likely occurred only once; in this case, all descendant species possess unusually elaborate spermathecae. Data further indicate that the seminal receptacle is the primary sperm-storage organ in Drosophila. This organ exhibits a pattern of strong correlated evolution with the length of sperm. The evolution of multiple kinds of female sperm-storage organs and the rapidly divergent and correlated evolution of sperm and female reproductive tract morphology are discussed.
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Affiliation(s)
- Scott Pitnick
- Department of Biology, Syracuse University, 108 College Place, Syracuse, New York, 13244-1270
| | - Therese Marrow
- Department of Zoology, Arizona State University, Tempe, Arizona, 85287-1501
| | - Greg S Spicer
- Department of Biology, San Francisco State University, San Francisco, California, 94132-1722
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Avila FW, Mattei AL, Wolfner MF. Sex peptide receptor is required for the release of stored sperm by mated Drosophila melanogaster females. JOURNAL OF INSECT PHYSIOLOGY 2015; 76:1-6. [PMID: 25783955 PMCID: PMC4430431 DOI: 10.1016/j.jinsphys.2015.03.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 02/11/2015] [Accepted: 03/04/2015] [Indexed: 05/23/2023]
Abstract
The storage of sperm in mated females is important for efficient reproduction. After sperm are transferred to females during mating, they need to reach and enter into the site(s) of storage, be maintained viably within storage, and ultimately be released from storage to fertilize eggs. Perturbation of these events can have drastic consequences on fertility. In Drosophila melanogaster, females store sperm for up to 2 weeks after a single mating. For sperm to be released normally from storage, Drosophila females need to receive the seminal fluid protein (SFP) sex peptide (SP) during mating. SP, which binds to sperm in storage, signals through the sex peptide receptor (SPR) to elicit two other effects on mated females: the persistence of egg laying and a reduction in sexual receptivity. However, it is not known whether SPR is also needed to mediate SP's effect on sperm release. By phenotypic analysis of flies deleted for SPR, and of flies knocked down for SPR, ubiquitously or in specific tissues, we show that SPR is required to mediate SP's effects on sperm release from storage. We show that SPR expression in ppk(+) neurons is needed for proper sperm release; these neurons include those that mediate SP's effect on receptivity and egg laying. However, we find that SPR is also needed in the spermathecal secretory cells of the female reproductive tract for efficient sperm release. Thus, SPR expression is necessary in both the nervous system and in female reproductive tract cells to mediate the release of stored sperm.
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Affiliation(s)
- Frank W Avila
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Alexandra L Mattei
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
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Orr TJ, Brennan PLR. Sperm storage: distinguishing selective processes and evaluating criteria. Trends Ecol Evol 2015; 30:261-72. [PMID: 25843274 DOI: 10.1016/j.tree.2015.03.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/05/2015] [Accepted: 03/06/2015] [Indexed: 01/18/2023]
Abstract
Sperm storage, the extended maintenance of viable sperm, probably occurs in most internally fertilizing animals. Because it temporally separates mating from conception, sperm storage can be adaptive in ecologically diverse habitats and affect life histories, mating systems, cryptic female choice, sperm competition, and sexual conflict. Sperm storage can result from different selective forces acting on females and/or males, sometimes resulting in coevolution. The various criteria often used to determine the presence of sperm storage in any given taxon can result from the action of any one or all of these selective forces. Here we discuss the criteria used to study sperm storage and how we can use these to better understand the evolution of diversity in sperm-storage adaptations.
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Affiliation(s)
- Teri J Orr
- Departments of Psychology and Biology, and Organismic and Evolutionary Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA.
| | - Patricia L R Brennan
- Departments of Psychology and Biology, and Organismic and Evolutionary Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA
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Sbilordo SH, Martin OY. Pre- and postcopulatory sexual selection act in concert to determine male reproductive success inTribolium castaneum. Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12262] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Sonja H. Sbilordo
- ETH Zürich; Institute of Integrative Biology (IBZ); D-USYS; Universitätsstrasse 16 8092 Zürich Switzerland
| | - Oliver Y. Martin
- ETH Zürich; Institute of Integrative Biology (IBZ); D-USYS; Universitätsstrasse 16 8092 Zürich Switzerland
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11
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Al-Wathiqui N, Lewis SM, Dopman EB. Using RNA sequencing to characterize female reproductive genes between Z and E Strains of European Corn Borer moth (Ostrinia nubilalis). BMC Genomics 2014; 15:189. [PMID: 24621199 PMCID: PMC4007636 DOI: 10.1186/1471-2164-15-189] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/03/2014] [Indexed: 11/29/2022] Open
Abstract
Background Reproductive proteins often evolve rapidly and are thought to be subject to strong sexual selection, and thus may play a key role in reproductive isolation and species divergence. However, our knowledge of reproductive proteins has been largely limited to males and model organisms with sequenced genomes. With advances in sequencing technology, Lepidoptera are emerging models for studies of sexual selection and speciation. By profiling the transcriptomes of the bursa copulatrix and bursal gland from females of two incipient species of moth, we characterize reproductive genes expressed in the primary reproductive tissues of female Lepidoptera and identify candidate genes contributing to a one-way gametic incompatibility between Z and E strains of the European corn borer (Ostrinia nubilalis). Results Using RNA sequencing we identified transcripts from ~37,000 and ~36,000 loci that were expressed in the bursa copulatrix or the bursal gland respectively. Of bursa copulatrix genes, 8% were significantly differentially expressed compared to the female thorax, and those that were up-regulated or specific to the bursa copulatrix showed functional biases toward muscle activity and/or organization. In the bursal gland, 9% of genes were differentially expressed compared to the thorax, with many showing reproduction or gamete production functions. Of up-regulated bursal gland genes, 46% contained a transmembrane region and 16% possessed secretion signal peptides. Divergently expressed genes in the bursa copulatrix were exclusively biased toward protease-like functions and 51 proteases or protease inhibitors were divergently expressed overall. Conclusions This is the first comprehensive characterization of female reproductive genes in any lepidopteran system. The transcriptome of the bursa copulatrix supports its role as a muscular sac that is the primary site for disruption of the male ejaculate. We find that the bursal gland acts as a reproductive secretory body that might also interact with male ejaculate. In addition, differential expression of proteases between strains supports a potential role for these tissues in contributing to reproductive isolation. Our study provides new insight into how male ejaculate is processed by female Lepidoptera, and paves the way for future work on interactions between post-mating sexual selection and speciation. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-189) contains supplementary material, which is available to authorized users.
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12
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Yu N, Nachman RJ, Smagghe G. Characterization of sulfakinin and sulfakinin receptor and their roles in food intake in the red flour beetle Tribolium castaneum. Gen Comp Endocrinol 2013; 188:196-203. [PMID: 23524001 DOI: 10.1016/j.ygcen.2013.03.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 03/02/2013] [Accepted: 03/04/2013] [Indexed: 01/06/2023]
Abstract
Sulfakinins (SK) are multifunctional neuropeptides widely found in insects that are structurally and functionally homologous to the mammalian gastrin/cholecystokinin (CCK) neuropeptides. CCK is involved in various biological processes such as the feeding regulation where it induces satiety. In this project we characterized SK and SK receptor (SKR) of an important pest and model beetle insect, the red flour beetle Tribolium castaneum, with the aim to better understand the SK signaling pathway and its function in food intake. The sk gene encoded a SK precursor with 113 amino acids and the skr gene a seven-transmembrane SKR with 554 amino acids. Both genes were expressed in the larval, pupal and adult stages with different expression levels in tested tissues. By RNA interference, sk dsRNA and skr dsRNA reduced the expression of the corresponding target gene by 80-90% and 30-50%, respectively, and stimulated food intake in the larvae. In parallel, we injected insects with a SK analog reducing food intake. In conclusion, the data are discussed in relation to the SK signaling pathway and its physiological-endocrinological role in regulating food intake and potential usage in the control of important pest insects.
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Affiliation(s)
- Na Yu
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
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Yu N, Benzi V, Zotti MJ, Staljanssens D, Kaczmarek K, Zabrocki J, Nachman RJ, Smagghe G. Analogs of sulfakinin-related peptides demonstrate reduction in food intake in the red flour beetle, Tribolium castaneum, while putative antagonists increase consumption. Peptides 2013; 41:107-12. [PMID: 23246802 DOI: 10.1016/j.peptides.2012.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 12/04/2012] [Accepted: 12/05/2012] [Indexed: 01/28/2023]
Abstract
The insect sulfakinins (SKs) constitute a family of neuropeptides that display both structural and functional similarities to the mammalian hormones gastrin and cholecystokinin (CCK). As a multifunctional neuropeptide, SKs are involved in muscle contractions as well as food intake regulation in many insects. In the red flour beetle Tribolium castaneum, the action on food intake by a series of synthetic SK analogs and one putative antagonist was investigated by injection in beetle adults. The most remarkable result was that both sulfated and non-sulfated SKs [FDDY(SO3H)GHMRFamide] inhibited food intake by about 70%. Strong activity observed for SK analogs featuring a residue that mimics the acidic nature of Tyr(SO3H) but lack the phenyl ring of Tyr, indicate that aromaticity is not a critical characteristic for this position of the peptide. SK demonstrated considerable tolerance to Ser and Ala substitution in position 8 (basic Arg), as analogs featuring these uncharged substitutions retained almost all of the food intake inhibitory activity. Also, the Phe in position 1 could be replaced by Ser without complete loss of activity. Conversely, substitution of Met by Nle in position 7 led to inactive compounds. Finally, the Caenorhabditis elegans sulfated neuropeptide-like protein-12 (NLP-12), that shares some sequence similarities with the SKs but features a Gln-Phe-amide rather than an Arg-Phe-amide at the C-terminus, elicited increased food intake in T. castaneum, which may indicate an antagonist activity. Co-injection of NLP-12 with nsSK blocked the food intake inhibitory effects of nsSK.
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Affiliation(s)
- Na Yu
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
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14
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Large neurological component to genetic differences underlying biased sperm use in Drosophila. Genetics 2012; 193:177-85. [PMID: 23105014 DOI: 10.1534/genetics.112.146357] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Sperm competition arises as a result of complex interactions among male and female factors. While the roles of some male factors are known, little is known of the molecules or mechanisms that underlie the female contribution to sperm competition. The genetic tools available for Drosophila allow us to identify, in an unbiased manner, candidate female genes that are critical for mediating sperm competition outcomes. We first screened for differences in female sperm storage and use patterns by characterizing the natural variation in sperm competition in a set of 39 lines from the sequenced Drosophila Genetic Reference Panel (DGRP) of wild-derived inbred lines. We found extensive female variation in sperm competition outcomes. To generate a list of candidate female genes for functional studies, we performed a genome-wide association mapping, utilizing the common single-nucleotide polymorphisms (SNPs) segregating in the DGRP lines. Surprisingly, SNPs within ion channel genes and other genes with roles in the nervous system were among the top associated SNPs. Knockdown studies of three candidate genes (para, Rab2, and Rim) in sensory neurons innervating the female reproductive tract indicate that some of these candidate female genes may affect sperm competition by modulating the neural input of these sensory neurons to the female reproductive tract. More extensive functional studies are needed to elucidate the exact role of all these candidate female genes in sperm competition. Nevertheless, the female nervous system appears to have a previously unappreciated role in sperm competition. Our results indicate that the study of female control of sperm competition should not be limited to female reproductive tract-specific genes, but should focus also on diverse biological pathways.
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15
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Should he stay or should he go: male influence on offspring sex ratio via postcopulatory attendance. Behav Ecol Sociobiol 2012. [DOI: 10.1007/s00265-012-1369-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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A requirement for the neuromodulators octopamine and tyramine in Drosophila melanogaster female sperm storage. Proc Natl Acad Sci U S A 2012; 109:4562-7. [PMID: 22393023 DOI: 10.1073/pnas.1117689109] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Female sperm storage is common among organisms with internal fertilization. It is important for extended fertility and, in cases of multiple mating, for sperm competition. The physiological mechanisms by which females store and manage stored sperm are poorly understood. Here, we report that the biogenic amines tyramine (TA) and octopamine (OA) in Drosophila melanogaster females play essential roles in sperm storage. D. melanogaster females store sperm in two types of organs, a single seminal receptacle and a pair of spermathecae. We examined sperm storage parameters in females mutant in enzymes required for the biochemical synthesis of tyrosine to TA and TA to OA, respectively. Postmating uterine conformational changes, which are associated with sperm entry and accumulation into storage, were unaffected by the absence of either TA or OA. However, sperm release from storage requires both TA and OA; sperm were retained in storage in both types of mutant females at significantly higher levels than in control flies. Absence of OA inhibited sperm depletion only from the seminal receptacle, whereas absence of both OA and TA perturbed sperm depletion from both storage organ types. We find innervation of the seminal receptacle and spermathecae by octopaminergic-tyraminergic neurons. These findings identify a distinct role for TA and OA in reproduction, regulating the release of sperm from storage, and suggest a mechanism by which Drosophila females actively regulate the release of stored sperm.
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Prokupek AM, Eyun SI, Ko L, Moriyama EN, Harshman LG. Molecular evolutionary analysis of seminal receptacle sperm storage organ genes of Drosophila melanogaster. J Evol Biol 2010; 23:1386-98. [PMID: 20500366 DOI: 10.1111/j.1420-9101.2010.01998.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Sperm storage organs are common and broadly distributed among animal taxa. However, little is known about how these organs function at the molecular level. Additionally, there is a paucity of knowledge about the evolution of genes expressed in these organs. This investigation is an evolutionary expressed sequence tag (EST) study of genes expressed in the seminal receptacle, one of the sperm storage organs in Drosophila. The incidence of positive selection is higher for the seminal receptacle genes than Drosophila reproductive genes as a whole, but lower than genes associated with the spermatheca, a second type of Drosophila sperm storage organ. By identifying overrepresented classes of proteins and classes for which sperm storage function is suggested by the nature of the proteins, candidate genes were discovered. These candidates belong to protein classes such as muscle contraction, odorant binding and odorant receptor, protease inhibitor and immunity.
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Affiliation(s)
- A M Prokupek
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
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19
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deCarvalho TN, Shaw KL. Elaborate courtship enhances sperm transfer in the Hawaiian swordtail cricket, Laupala cerasina. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2009.12.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fedina TY, Lewis SM. An integrative view of sexual selection in Tribolium flour beetles. Biol Rev Camb Philos Soc 2008; 83:151-71. [PMID: 18429767 DOI: 10.1111/j.1469-185x.2008.00037.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sexual selection is a major force driving the evolution of diverse reproductive traits. This evolutionary process is based on individual reproductive advantages that arise either through intrasexual competition or through intersexual choice and conflict. While classical studies of sexual selection focused mainly on differences in male mating success, more recent work has focused on the differences in paternity share that may arise through sperm competition or cryptic female choice whenever females mate with multiple males. Thus, an integrative view of sexual selection needs to encompass processes that occur not only before copulation (pre-mating), but also during copulation (peri-mating), as well as after copulation (post-mating), all of which can generate differences in reproductive success. By encompassing mechanisms of sexual selection across all of these sequential reproductive stages this review takes an integrative approach to sexual selection in Tribolium flour beetles (Coleoptera: Tenebrionidae), a particularly well-studied and economically important model organism. Tribolium flour beetles colonize patchily distributed grain stores, and juvenile and adult stages share the same food resources. Adults are highly promiscuous and female reproduction is distributed across an adult lifespan lasting approximately 1 year. While Tribolium males produce an aggregation pheromone that attracts both sexes, there appears to be little pre-mating discrimination among potential mates by either sex. However, recent work has revealed several peri-mating and post-mating mechanisms that determine how offspring paternity is apportioned among a female's mates. During mating, Tribolium females reject spermatophore transfer and limit sperm numbers transferred by males with low phenotypic quality. Although there is some conflicting evidence, male copulatory leg-rubbing appears to be associated with overcoming female resistance to insemination and does not influence a male's subsequent paternity share. Evidence suggests that Tribolium beetles have several possible post-mating mechanisms that they may use to bias paternity. Male sperm precedence has been extensively studied in Tribolium spp. and the related Tenebrio molitor, and several factors influencing male paternity share among a female's progeny have been identified. These include oviposition time, inter-mating interval, male strain/genotype, the mating regimen of a male's mother, male starvation, and tapeworm infection. Females exert muscular control over sperm storage, although there is no evidence to date that females use this to differentiate among mates. Females could also influence offspring paternity by re-mating with additional males, and T. castaneum females more readily accept spermatophores when they are re-mating with more attractive males. Additional work is needed to examine the possible roles played by both male and female accessory gland products in determining male paternity share. Sexual selection during pre-mating episodes may be reinforced or counteracted by peri- and post-copulatory selection, and antagonistic coevolution between the sexes may be played out across reproductive stages. In Tribolium, males' olfactory attractiveness is positively correlated with both insemination success and paternity share, suggesting consistent selection across different reproductive stages. Similar studies across sequential reproductive stages are needed in other taxa to provide a more integrative view of sexual selection.
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ARNAUD LUDOVIC, HAUBRUGE ERIC, GAGE MATTHEWJG. Sperm size and number variation in the red flour beetle. Zool J Linn Soc 2008. [DOI: 10.1111/j.1096-3642.2001.tb00631.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
The flagellosperm of insects, although following a general ground plan, exhibit considerable variation in morphology and ultrastructure across taxa, consistent with a history of rapid and divergent evolution. Sperm competition, which occurs when sperm of two or more males compete for the fertilization of a female's ova, has been recognized as a significant driving force in the evolution of insect sperm structure. Despite a considerable volume of data on sperm morphology, little is known about the motility of insect sperm. Understanding insect sperm motility would help to refine models of sexual selection on insect sperm, and would throw light on the selective mechanisms that shape insect sperm structure and function. This review updates our present knowledge of the proximate and ultimate aspects of insect sperm motility.
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Affiliation(s)
- Michael Werner
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, WA 6009, Australia.
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Pai A, Bernasconi G. Polyandry and female control: the red flour beetle Tribolium castaneum as a case study. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2008; 310:148-59. [PMID: 17358014 DOI: 10.1002/jez.b.21164] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Females of many animal species are polyandrous, and there is evidence that they can control pre- and post-mating events. There has been a growing interest in consequences of polyandry for male and female reproductive success and offspring fitness, and its evolutionary significance. In several taxa, females exhibit mate choice both before and after mating and can influence the paternity of their offspring, enhancing offspring number and quality, but potentially countering male interests. Studying female mating biology and in particular post-copulatory female control mechanisms thus promises to yield insights into sexual selection and the potential of male-female coevolution. Here, we highlight the red flour beetle Tribolium castaneum (Herbst), a storage pest, as a model system to study polyandry, and review studies addressing the effects of polyandry on male sperm competitive ability and female control of post-mating events. These studies show that the outcome of sperm competition in the red flour beetle is influenced by both male and female traits. Furthermore, recent advances suggest that sexual conflict may have shaped reproductive traits in this species.
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Affiliation(s)
- Aditi Pai
- Department of Biology, Spelman College, Atlanta, Georgia, USA.
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24
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Abstract
Although female mate choice and male sperm competition have separately attracted much attention, few studies have addressed how precopulatory and postcopulatory episodes of sexual selection might interact to drive the evolution of male traits. In Photinus fireflies, females preferentially respond to males based on their bioluminescent courtship signals, and females gain direct benefits through male nuptial gifts acquired during multiple matings over several nights. We experimentally manipulated matings of P. greeni fireflies to test the hypothesis that postcopulatory paternity success might be biased toward males that are more attractive during courtship interactions. We first measured male courtship attractiveness to individual females using field behavioral assays. Females were then assigned to two double-mating treatments: (1) least attractive second male-females were first mated with their most attractive male, followed by their least attractive male, or (2) most attractive second male-females mated with males in reverse order. Larval offspring produced by each female following these double matings were genotyped using random amplified polymorphic DNA (RAPD) markers, and male paternity was determined. Contrary to prediction, firefly males that were more attractive to females based on their bioluminescent courtship displays subsequently showed significantly lower paternity, reflecting possible male trade-offs or sexual conflict. Differences in male paternity were not related to male body condition, testes or accessory gland mass, or to variation in female spermathecal size. Additionally, this study suggests that changes in phenotypic selection gradients may occur during different reproductive stages. These results indicate that it is crucial for future studies on sexual selection in polyandrous species to integrate both precopulatory and postcopulatory episodes to fully understand the evolution of male traits.
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Affiliation(s)
- Kristian C Demary
- Department of Biology, Tufts University, Medford, Massachusetts 02155, USA.
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25
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Adams EM, Wolfner MF. Seminal proteins but not sperm induce morphological changes in the Drosophila melanogaster female reproductive tract during sperm storage. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:319-31. [PMID: 17276455 PMCID: PMC2144743 DOI: 10.1016/j.jinsphys.2006.12.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 12/05/2006] [Accepted: 12/06/2006] [Indexed: 05/12/2023]
Abstract
In most insects, sperm transferred by the male to the female during mating are stored within the female reproductive tract for subsequent use in fertilization. In Drosophila melanogaster, male accessory gland proteins (Acps) within the seminal fluid are required for efficient accumulation of sperm in the female's sperm storage organs. To determine the events within the female reproductive tract that occur during sperm storage, and the role that Acps and sperm play in these events, we identified morphological changes that take place during sperm storage in females mated to wild-type, Acp-deficient or sperm-deficient males. A reproducible set of morphological changes occurs in a wild-type mating. These were categorized into 10 stereotypic stages. Sperm are not needed for progression through these stages in females, but receipt of Acps is essential for progression beyond the first few stages of morphological change. Furthermore, females that received small quantities of Acps reached slightly later stages than females that received no Acps. Our results suggest that timely morphological changes in the female reproductive tract, possibly muscular in nature, may be needed for successful sperm storage, and that Acps from the male are needed in order for these changes to occur.
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Affiliation(s)
- Erika M Adams
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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26
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Fedina TY. Cryptic female choice during spermatophore transfer in Tribolium castaneum (Coleoptera: Tenebrionidae). JOURNAL OF INSECT PHYSIOLOGY 2007; 53:93-8. [PMID: 17161846 DOI: 10.1016/j.jinsphys.2006.10.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 10/15/2006] [Accepted: 10/26/2006] [Indexed: 05/12/2023]
Abstract
Sexual selection in both males and females promotes traits and behaviors that allow control over paternity when female mates with multiple males. Nonetheless, mechanisms of cryptic female choice have been consistently overlooked, due to traditional focus on sperm competition as well as difficulty in distinguishing male vs. female influence over processes occurring during and after mating. The first part of this study describes morphology and transformation of Tribolium castaneum spermatophores inferred from dissecting females immediately after normal or interrupted copulations. T. castaneum males are found to transfer spermatophores as an invaginated tube that everts inside the female bursa and which is filled with sperm during copulation. This sequence of events makes it feasible for females to control the sperm quantity transferred in each spermatophore. Through manipulation of the male phenotypic quality (by starvation) and manipulation of female control over sperm transfer (by killing a subset of females), the second part of this study examines whether females use control over transferred sperm quantity as a cryptic choice mechanism. Fed males transferred significantly more sperm per spermatophore than starved males but only when mating with live females. These results suggest an active differentiation by live females against starved males and provide an evidence for the proposed cryptic female choice mechanism.
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Affiliation(s)
- Tatyana Y Fedina
- Department of Biology, Tufts University, Medford, MA 02155, USA.
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Fedina TY, Lewis SM. Proximal traits and mechanisms for biasing paternity in the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae). Behav Ecol Sociobiol 2006. [DOI: 10.1007/s00265-006-0228-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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BEESE KATHLEEN, BAUR BRUNO. Expandable spermatheca influences sperm storage in the simultaneously hermaphroditic snailArianta arbustorum. INVERTEBR REPROD DEV 2006. [DOI: 10.1080/07924259.2006.9652198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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29
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Pai A, Bennett L, Yan G. Female multiple mating for fertility assurance in red flour beetles (Tribolium castaneum). CAN J ZOOL 2005. [DOI: 10.1139/z05-073] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The costs of mating with multiple partners include expenditure of energy and time and a reduction in lifespan, but females of many taxa mate with several different partners shortly after their first copulation. Often it is not clear what females gain from this behaviour. In this study, we used the red flour beetle (Tribolium castaneum Herbst, 1797) to test the hypothesis that females mate with multiple males for fertility assurance because the first copulation often does not lead to offspring production. We found that the probability of producing offspring, as measured by the proportion of females that produced offspring, was not affected by multiple mating when females were mated to virgin partners. However, when females were mated to nonvirgin partners, multiple mating led to an increased probability of producing offspring. To establish the mechanism through which multiple mating enhanced the probability of producing offspring, we further investigated whether this result was observed because multiple mating provided genetically compatible sperm or because it provided sufficient sperm. Viability of larvae from multiply mated females was higher than that of larvae from singly mated females, but the total number of adult offspring produced was not significantly different between the two groups. The capacity of males to inseminate females decreased in successive matings after the initial copulation, suggesting that ineffective copulations between virgin females and nonvirgin males are likely due to male sperm depletion. Therefore, mating with multiple males increased the probability that females would produce offspring and served as fertility assurance.
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Demary KC. Sperm storage and viability in Photinus fireflies. JOURNAL OF INSECT PHYSIOLOGY 2005; 51:837-41. [PMID: 15927199 DOI: 10.1016/j.jinsphys.2005.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2005] [Revised: 04/01/2005] [Accepted: 04/02/2005] [Indexed: 05/02/2023]
Abstract
In many species females mate with and store sperm from multiple males, and some female insects have evolved multiple compartments for sperm storage. Sperm storage and sperm viability were investigated in two firefly species, Photinus greeni and P. ignitus, which differ in the morphology of the female reproductive tract. Although the primary spermatheca is similar in both species, P. greeni females have an additional, conspicuous outpocketing within the bursa copulatrix whose potential role in sperm storage was investigated in this study. An assay that distinguishes between live and dead sperm was used to examine sperm viability in male seminal vesicles and sperm storage sites within the female reproductive tract. For both Photinus species, sperm from male seminal vesicles showed significantly higher viability compared to sperm from the primary spermatheca of single mated females. In single mated P. greeni females, sperm taken from the channel outpocketing (secondary spermatheca) showed significantly higher viability compared to sperm from the primary spermatheca. This sperm viability difference was not evident in double mated females. There were no significant differences between P. greeni and P. ignitus females in the viability of sperm from the primary spermatheca. These studies contribute to our understanding of post-mating processes that may influence paternity success, and suggest that sexual conflict over control of fertilizations may occur in multiply mated firefly females.
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31
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House CM, Simmons LW. Relative influence of male and female genital morphology on paternity in the dung beetle Onthophagus taurus. Behav Ecol 2005. [DOI: 10.1093/beheco/ari066] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Fedina TY, Lewis SM. Female influence over offspring paternity in the red flour beetle Tribolium castaneum. Proc Biol Sci 2004; 271:1393-9. [PMID: 15306338 PMCID: PMC1691742 DOI: 10.1098/rspb.2004.2731] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In animals having internal fertilization, both sexes can potentially influence the post-copulatory processes of sperm transfer, sperm storage and sperm use for fertilization. In this experiment, we investigated whether Tribolium castaneum females can influence male paternity success following consecutive matings with two different males. We compared second male paternity success (P2) between females exposed to carbon dioxide (CO2) and control females kept in air, in both cases for 30 min between two matings. CO2 exposure inhibits muscular activity and has previously been shown to decrease sperm storage by T. castaneum females. Females exposed to CO2 after their first mating showed significantly higher P2 than control females during the later portion of a one-month oviposition period. These results are consistent with reduced storage of first male sperm by CO2-exposed females. Also, T. castaneum females showed considerable variation in spermathecal morphology, and P2 decreased with increasing spermathecal tubule volume. These results demonstrate that T. castaneum females can influence male paternity success, and suggest that differential sperm storage may be an important mechanism of post-copulatory female choice.
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Bloch Qazi MC, Wolfner MF. An early role for the Drosophila melanogaster male seminal protein Acp36DE in female sperm storage. J Exp Biol 2003; 206:3521-8. [PMID: 12939382 DOI: 10.1242/jeb.00585] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Female sperm storage is an essential component of reproduction in many animals. In insects, female sperm storage affects fecundity, sperm competition/preference and receptivity to re-mating. Female sperm storage consists of several stages, including sperm entry into the sperm storage organs (SSOs), maintenance within the SSOs and exit from the SSOs. The Drosophila melanogaster male seminal protein Acp36DE is essential for female sperm storage. Acp36DE associates with sperm and localizes to specific regions of the female reproductive tract, including the SSOs. We determined the stage of sperm storage at which Acp36DE acts by comparing the timing of initial sperm entry into storage as well as the rates of sperm accumulation and release from the SSOs in the presence or absence of Acp36DE. Acp36DE accelerates sperm accumulation into storage but does not mediate the entry of the first sperm into storage. This finding also demonstrates that the initial stage of sperm storage consists of multiple steps. Acp36DE enters the SSOs before sperm, and its residence within the SSOs does not require sperm. We propose that once sperm storage has initiated, Acp36DE acts as a guidance factor helping subsequent sperm move into storage, a corral concentrating sperm around the SSO entrances and/or a trigger for responses within the female that accelerate storage of sperm.
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Affiliation(s)
- Margaret C Bloch Qazi
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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34
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Abstract
Many female insects mate with multiple males within a single fertile period despite costs such as expenditure of energy and time and contraction of sexually transmitted diseases. In the red flour beetle, Tribolium castaneum, females remate with different males within minutes of the first copulation. If rapid multiple mating is adaptive then multiply mated females should have higher fitness than singly mated females. In this study, we determined the remating frequency of female beetles, characterized female mating behavior, and examined the fitness consequences of female multiple mating. We found that female T. castaneum mated, on average, with 46 nonvirgin males within a 1-h observation period. The number of males present in a mating arena did not significantly affect copulation frequency or the intermating interval. However, number of males present significantly affected the length of a single copula as a result of disturbance by rival males when more males were present. Female mating with multiple males in 24 h did not significantly improve egg production, F1-adult production, egg-to-adult viability, fertility retention, and female survivorship. Thus, multiple mating did not enhance long-term female fitness. Polyandrous mating behavior may have evolved through other mechanisms such as fertility assurance and increased offspring genetic diversity or fitness.
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35
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Bloch Qazi MC, Heifetz Y, Wolfner MF. The developments between gametogenesis and fertilization: ovulation and female sperm storage in Drosophila melanogaster. Dev Biol 2003; 256:195-211. [PMID: 12679097 DOI: 10.1016/s0012-1606(02)00125-2] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In animals with internal fertilization, ovulation and female sperm storage are essential steps in reproduction. While these events are often required for successful fertilization, they remain poorly understood at the developmental and molecular levels in many species. Ovulation involves the regulated release of oocytes from the ovary. Female sperm storage consists of the movement of sperm into, maintenance within, and release from specific regions of the female reproductive tract. Both ovulation and sperm storage elicit important changes in gametes: in oocytes, ovulation can trigger changes in the egg envelopes and the resumption of meiosis; for sperm, storage is a step in their transition from being "movers" to "fertilizers." Ovulation and sperm storage both consist of timed and directed cell movements within a morphologically and chemically complex environment (the female reproductive tract), culminating with gamete fusion. We review the processes of ovulation and sperm storage for Drosophila melanogaster, whose requirements for gamete maturation and sperm storage as well as powerful molecular genetics make it an excellent model organism for study of these processes. Within the female D. melanogaster, both processes are triggered by male factors during and after mating, including sperm and seminal fluid proteins. Therefore, an interplay of male and female factors coordinates the gametes for fertilization.
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Affiliation(s)
- Margaret C Bloch Qazi
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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36
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House CM, Simmons LW. Genital morphology and fertilization success in the dung beetle Onthophagus taurus: an example of sexually selected male genitalia. Proc Biol Sci 2003; 270:447-55. [PMID: 12641898 PMCID: PMC1691274 DOI: 10.1098/rspb.2002.2266] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In animals with internal fertilization and promiscuous mating, male genitalia show rapid and divergent evolution. Three hypotheses have been suggested to explain the evolutionary processes responsible for genital evolution: the lock-and-key hypothesis, the pleiotropy hypothesis and the sexual-selection hypothesis. Here, we determine whether variation in male genital morphology influences fertilization success in the dung beetle Onthophagus taurus, as predicted by the sexual-selection hypothesis. Variation in four out of five genital sclerites of the endophallus influenced a male's fertilization success, supporting the general hypothesis that male genitalia can evolve under sexual selection. Furthermore, different genital sclerites were found to enhance first versus second male paternity, indicating that different sclerites serve offensive and defensive roles. Genital-trait variability was comparable to that in other species but was less variable than a non-genital sexually selected trait (head horns). We suggest that directional selection for genital elaboration may be countered by natural selection, which should favour genitalia of a size and shape necessary for efficient coupling and sperm transfer.
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Affiliation(s)
- Clarissa M House
- Evolutionary Biology Research Group, Department of Zoology, University of Western Australia, Nedlands, WA 6009, Australia.
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37
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Mack PD, Priest NK, Promislow DEL. Female age and sperm competition: last-male precedence declines as female age increases. Proc Biol Sci 2003; 270:159-65. [PMID: 12590754 PMCID: PMC1691224 DOI: 10.1098/rspb.2002.2214] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Until very recently, most studies of sperm competition have focused on variation in male competitive ability. However, we now know that a number of reproductive traits, including oviposition rate, use of stored sperm and receptivity to mating, vary with female condition. Because females can play an active part in the movement of sperm within their reproductive tract, sperm competition may be influenced by female condition. Existing studies of sperm competition in fruitflies ignore the effects of female condition, using females that are 3-4 days old and in their reproductive prime. But condition will decline as a female senesces. Here, we examine the effect of female age on the outcome of sperm competition in three strains of the fruitfly, Drosophila melanogaster. Previous studies have shown that female age influences preference for mates and male ejaculation strategies. In this study, we find that when males are mated to females that are older than 17 days, last-male sperm precedence decreases significantly. These results could lead to a greater understanding of the physiological mechanisms that regulate the outcome of sperm competition.
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Affiliation(s)
- Paul D Mack
- Department of Genetics, University of Georgia, Athens, GA 30602-7223, USA.
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38
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Abstract
In polyandrous mating systems, events occurring during copulation can alter the fate of the mating male's sperm. These events may exert selective pressures resulting in the evolution of diverse reproductive behaviours, morphologies and physiologies. This study investigates the role of male and female copulatory behaviours on sperm fate in the red flour beetle, Tribolium castaneum. I describe and quantify copulatory behaviours for mating pairs, and examine sperm fate by quantifying sperm transfer, sperm storage and second male sperm precedence. Whereas female quiescence during copulation and male leg rubbing during copulation together account for significant variation (26%) in sperm precedence, female copulatory quiescence alone provides information about the timing and numbers of sperm transferred. These experiments show that a female copulatory behaviour predicts sperm fate, and emphasize the value of studying variation in both male and female copulatory behaviours for understanding factors affecting sperm use.
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Affiliation(s)
- M C Bloch Qazi
- Department of Biology, Tufts University, Medford, MA, USA.
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Werner M, Tscheulin T, Speck T, Zissler D, Peschke K. Ultrastructure and motility pattern of the spermatozoa of Aleochara curtula (Coleoptera, Staphylinidae). ARTHROPOD STRUCTURE & DEVELOPMENT 2002; 31:243-254. [PMID: 18088984 DOI: 10.1016/s1467-8039(02)00046-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2002] [Accepted: 08/29/2002] [Indexed: 05/25/2023]
Abstract
Ultrastructure and motility pattern of spermatozoa of the rove beetle Aleochara curtula were examined using electron and light microscopic methods. The spermatozoon is about 100 microm long and filiform. The head piece comprises a 5 microm long triple layered acrosome and 10 microm long nucleus. The flagellum consists of a 9+9+2 axoneme, two accessory bodies and two mitochondrial derivatives about equal in size but of different shape in their cross sections. In both derivatives there are paracrystalline inclusions. The flagellum is attached to the head by a 2 microm long centriole adjunct which is characterized by its electron dense material that forms a three layered folded lamellar structure. When liberated in buffer solution the sperm flagella assume a coiled hook-like form with the excentric stiff head protruding in front. The spermatozoa are driven through the medium by a small helicoidal wave of high frequency superimposed to the bent flagella. The maximum speed measured was 15.2 microm/s. The sperm architecture of A. curtula is similar to that of other Aleochara species but differs in total length and dimensions of the mitochondrial derivatives. For that reason Aleochara sperm can certainly prove useful to study the effect of the mitochondrial derivatives on sperm motility.
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Affiliation(s)
- Michael Werner
- Institut für Biologie I (Zoologie), Hauptstr. 1, D-79104 Freiburg i.Br., Germany
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40
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41
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Abstract
The proportion of offspring sired by the second male to mate with a doubly mated female, P2, is a ubiquitously measured statistic in the study of insect sperm competition. Nevertheless, the underlying mechanisms of sperm transfer, storage, and use that determine P2 are poorly understood. Typically the second male to mate gains moderate to high paternity. More rarely, the first male to mate gains the majority of fertilizations. Here we examine the transfer, storage, and use of sperm in the bushcricket Requena verticalis, a species with male parental investment and almost complete first male paternity. Sperm drain from an externally attached spermatophore into the female's reproductive tract, where they are transported to the sperm store or spermatheca. We find that only sperm from the first male to mate are transported to the spermatheca. We provide some data that address a number of different mechanisms that might account for the lack of storage of second-male sperm. DNA microsatellite markers are developed to assign paternity. By manipulating the numbers of sperm transferred by first and second males, we show that the size of the ejaculate transferred by the first male has a major impact on paternity; increasing ejaculate size of the first male assures his paternity. Paternity assurance in R. verticalis holds significant implications for the evolution of paternal investment via the male's nuptial gift.
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Affiliation(s)
- L W Simmons
- Department of Zoology, University of Western Australia, Nedlands, Australia.
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42
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Edvardsson M, Arnqvist G. Copulatory courtship and cryptic female choice in red flour beetles Tribolium castaneum. Proc Biol Sci 2000; 267:559-63. [PMID: 10787158 PMCID: PMC1690577 DOI: 10.1098/rspb.2000.1037] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Males of many animal species engage in courtship behaviours during and after copulation that appear to be solely aimed at stimulating the female. It has been suggested that these behaviours have evolved by cryptic female choice, whereby females are thought to impose biases on male postmating paternity success. Males of the red flour beetle Tribolium castaneum rub the lateral edges of the females' elytra with their tarsi during copulation. We manipulated female perception of this behaviour by tarsal ablation in males, thus preventing males from reaching the edge of the female elytra with their manipulated legs, and by subsequently performing a series of double-mating experiments where the copulatory behaviour was quantified. We found a positive relationship between the intensity of the copulatory courtship behaviour and relative fertilization success among unmanipulated males. This pattern, however, was absent in manipulated males, where female perception of male behaviour differed from that actually performed. Thus, female perception of male copulatory courtship behaviour, rather than male behaviour per se, apparently governs the fate of sperm competing over fertilizations within the female, showing that copulatory courtship is under selection by cryptic female choice.
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Affiliation(s)
- M Edvardsson
- Department of Ecology and Environmental Science, University of Umeå, Sweden
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43
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Hellriegel B, Bernasconi G. Female-mediated differential sperm storage in a fly with complex spermathecae, Scatophaga stercoraria. Anim Behav 2000; 59:311-317. [PMID: 10675253 DOI: 10.1006/anbe.1999.1308] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Multiple spermathecae potentially allow selective sperm use, provided that sperm from rival males are stored differentially, that is, in different proportions across storage compartments. In the yellow dung fly, Scatophaga stercoraria, females have three spermathecae arranged as a doublet and singlet. To test whether females store the sperm of rival males actively and differentially, we mated fixed male pairs to three females. After copulation, females were (1) dissected immediately before they could start laying a clutch of eggs, (2) left awake for 30 min but prevented from oviposition, or (3) anaesthetized with carbon dioxide for 30 min to interfere with the muscular control presumably required for sperm transport from the site of insemination to the spermathecae. For each female, we estimated the proportion of the second male's sperm stored in her spermathecae (S(2)value), using sperm length as a male marker. After copulation, the S(2)values in the singlet and doublet spermathecae differed significantly, indicating differential sperm storage during copulation. Postcopulatory treatment affected differential sperm storage significantly. Females dissected immediately had lower S(2)values in the doublet than in the singlet spermatheca, while females left awake showed the reverse pattern for the same two males. This reversal did not occur when females were treated with carbon dioxide. The results indicate differential storage of sperm from different males during copulation and that female muscular activity can affect storage and separation of competing ejaculates beyond copulation. Copyright 2000 The Association for the Study of Animal Behaviour.
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