1
|
Ratiu AC, Ionascu A, Ecovoiu AA. A novel insertional allele of the CG18135 gene is associated with severe mutant phenotypes in Drosophila melanogaster. Front Genet 2024; 15:1355368. [PMID: 38957808 PMCID: PMC11217781 DOI: 10.3389/fgene.2024.1355368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 05/24/2024] [Indexed: 07/04/2024] Open
Abstract
Drosophila melanogaster has been at the forefront of genetic studies and biochemical modeling for over a century. Yet, the functions of many genes are still unknown, mainly because no phenotypic data are available. Herein, we present the first evidence data regarding the particular molecular and other quantifiable phenotypes, such as viability and anatomical anomalies, induced by a novel P{lacW} insertional mutant allele of the CG18135 gene. So far, the CG18135 functions have only been theorized based on electronic annotation and presumptive associations inferred upon high-throughput proteomics or RNA sequencing experiments. The descendants of individuals harboring the CG18135 P{lacW}CG18135 allele were scored in order to assess mutant embryonic, larval, and pupal viability versus Canton Special (CantonS). Our results revealed that the homozygous CG18135 P{lacW}CG18135 /CG18135 P{lacW}CG18135 genotype determines significant lethality both at the inception of the larval stage and during pupal development. The very few imago escapers that either breach or fully exit the puparium exhibit specific eye depigmentation, wing abnormal unfolding, strong locomotor impairment with apparent spasmodic leg movements, and their maximum lifespan is shorter than 2 days. Using the quantitative real-time PCR (qRT-PCR) method, we found that CG18135 is upregulated in male flies, but an unexpected gene upregulation was also detected in heterozygous mutants compared to wild-type flies, probably because of regulatory perturbations induced by the P{lacW} transposon. Our work provides the first phenotypic evidence for the essential role of CG18135, a scenario in accordance with the putative role of this gene in carbohydrate-binding processes.
Collapse
Affiliation(s)
- Attila Cristian Ratiu
- Drosophila Laboratory, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Academy of Romanian Scientists, Ilfov, Bucharest, Romania
| | - Adrian Ionascu
- Drosophila Laboratory, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Academy of Romanian Scientists, Ilfov, Bucharest, Romania
| | - Alexandru Al. Ecovoiu
- Drosophila Laboratory, Faculty of Biology, University of Bucharest, Bucharest, Romania
| |
Collapse
|
2
|
Majane AC, Cridland JM, Blair LK, Begun DJ. Evolution and genetics of accessory gland transcriptome divergence between Drosophila melanogaster and D. simulans. Genetics 2024; 227:iyae039. [PMID: 38518250 PMCID: PMC11151936 DOI: 10.1093/genetics/iyae039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 08/27/2023] [Accepted: 02/15/2024] [Indexed: 03/24/2024] Open
Abstract
Studies of allele-specific expression in interspecific hybrids have provided important insights into gene-regulatory divergence and hybrid incompatibilities. Many such investigations in Drosophila have used transcriptome data from complex mixtures of many tissues or from gonads, however, regulatory divergence may vary widely among species, sexes, and tissues. Thus, we lack sufficiently broad sampling to be confident about the general biological principles of regulatory divergence. Here, we seek to fill some of these gaps in the literature by characterizing regulatory evolution and hybrid misexpression in a somatic male sex organ, the accessory gland, in F1 hybrids between Drosophila melanogaster and D. simulans. The accessory gland produces seminal fluid proteins, which play an important role in male and female fertility and may be subject to adaptive divergence due to male-male or male-female interactions. We find that trans differences are relatively more abundant than cis, in contrast to most of the interspecific hybrid literature, though large effect-size trans differences are rare. Seminal fluid protein genes have significantly elevated levels of expression divergence and tend to be regulated through both cis and trans divergence. We find limited misexpression (over- or underexpression relative to both parents) in this organ compared to most other Drosophila studies. As in previous studies, male-biased genes are overrepresented among misexpressed genes and are much more likely to be underexpressed. ATAC-Seq data show that chromatin accessibility is correlated with expression differences among species and hybrid allele-specific expression. This work identifies unique regulatory evolution and hybrid misexpression properties of the accessory gland and suggests the importance of tissue-specific allele-specific expression studies.
Collapse
Affiliation(s)
- Alex C Majane
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Julie M Cridland
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Logan K Blair
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - David J Begun
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| |
Collapse
|
3
|
Gordon K, Gonzales P, Lee C, Marcin J, Takashima Y, Lazzaro B, Wolfner M. Drosophila Arc1 is not required for male fertility or sperm competition success. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.001053. [PMID: 38089935 PMCID: PMC10714220 DOI: 10.17912/micropub.biology.001053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/27/2023] [Accepted: 11/27/2023] [Indexed: 02/01/2024]
Abstract
Activity-regulated cytoskeleton associated protein (Arc1), which is required for synaptic plasticity and metabolism in Drosophila , self-assembles into capsid-like structures that transport mRNAs in extracellular vesicles. In addition to expression in the brain and nervous system, Arc1 is expressed in the male accessory glands, an endothelial tissue that produces male seminal proteins and exosomes that impact male fertility. We thus hypothesized that Arc1 might impact male fertility. We measured the fertility, mating latency, mating duration, and sperm competition performance of Arc1 males relative to controls and found no evidence that Arc1 is required for any of these measures of male fertility.
Collapse
Affiliation(s)
- Kathleen Gordon
- Department of Entomology, Cornell University, Ithaca, New York, United States
| | - Patrick Gonzales
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States
| | - Caroline Lee
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States
| | - Jeremy Marcin
- Department of Entomology, Cornell University, Ithaca, New York, United States
| | - Yoko Takashima
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States
| | - Brian Lazzaro
- Department of Entomology, Cornell University, Ithaca, New York, United States
| | - Mariana Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States
| |
Collapse
|
4
|
Takashima YA, Majane AC, Begun DJ. Evolution of secondary cell number and position in the Drosophila accessory gland. PLoS One 2023; 18:e0278811. [PMID: 37878630 PMCID: PMC10599531 DOI: 10.1371/journal.pone.0278811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 04/25/2023] [Indexed: 10/27/2023] Open
Abstract
In animals with internal fertilization, males transfer gametes and seminal fluid during copulation, both of which are required for successful reproduction. In Drosophila and other insects, seminal fluid is produced in the paired accessory gland (AG), the ejaculatory duct, and the ejaculatory bulb. The D. melanogaster AG has emerged as an important model system for this component of male reproductive biology. Seminal fluid proteins produced in the Drosophila AG are required for proper storage and use of sperm by the females, and are also critical for establishing and maintaining a suite of short- and long-term postcopulatory female physiological responses that promote reproductive success. The Drosophila AG is composed of two main cell types. The majority of AG cells, which are referred to as main cells, are responsible for production of many seminal fluid proteins. A minority of cells, about 4%, are referred to as secondary cells. These cells, which are restricted to the distal tip of the D. melanogaster AG, may play an especially important role in the maintenance of the long-term female post-mating response. Many studies of Drosophila AG evolution have suggested that the proteins produced in the gland evolve quickly, as does the transcriptome. Here, we investigate the evolution of secondary cell number and position in the AG in a collection of eight species spanning the entire history of the Drosophila genus. We document a heretofore underappreciated rapid evolutionary rate for both number and position of these specialized AG cells, raising several questions about the developmental, functional, and evolutionary significance of this variation.
Collapse
Affiliation(s)
- Yoko A. Takashima
- Department of Evolution and Ecology, University of California, Davis, California, United States of America
| | - Alex C. Majane
- Department of Evolution and Ecology, University of California, Davis, California, United States of America
| | - David J. Begun
- Department of Evolution and Ecology, University of California, Davis, California, United States of America
| |
Collapse
|
5
|
Patlar B, Fulham L, Civetta A. A predominant role of genotypic variation in both expression of sperm competition genes and paternity success in Drosophila melanogaster. Proc Biol Sci 2023; 290:20231715. [PMID: 37727083 PMCID: PMC10509582 DOI: 10.1098/rspb.2023.1715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 08/25/2023] [Indexed: 09/21/2023] Open
Abstract
Sperm competition is a crucial aspect of male reproductive success in many species, including Drosophila melanogaster, and seminal fluid proteins (Sfps) can influence sperm competitiveness. However, the combined effect of environmental and genotypic variation on sperm competition gene expression remains poorly understood. Here, we used Drosophila Genetic Reference Panel (DGRP) inbred lines and manipulated developmental population density (i.e. larval density) to test the effects of genotype, environment and genotype-by-environment interactions (GEI) on the expression of the known sperm competition genes Sex Peptide, Acp36DE and CG9997. High larval density resulted in reduced adult body size, but expression of sperm competition genes remained unaffected. Furthermore, we found no significant GEI but genotypic effects in the expression of SP and Acp36DE. Our results also revealed GEI for relative competitive paternity success (second male paternity; P2), with genes' expression positively correlated with P2. Given the effect of genotype on the expression of genes, we conducted a genome-wide association study (GWAS) and identified polymorphisms in putative cis-regulatory elements as predominant factors regulating the expression of SP and Acp36DE. The association of genotypic variation with sperm competition outcomes, and the resilience of sperm competition genes' expression against environmental challenges, demonstrates the importance of genome variation background in reproductive fitness.
Collapse
Affiliation(s)
- Bahar Patlar
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada R3B 2E9
| | - Lauren Fulham
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada R3B 2E9
| | - Alberto Civetta
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada R3B 2E9
| |
Collapse
|
6
|
Morimoto J, McDonald GC, Wigby S. Social group composition modulates the role of last male sperm precedence in post-copulatory sexual selection. J Evol Biol 2023; 36:1102-1115. [PMID: 37341163 PMCID: PMC10946607 DOI: 10.1111/jeb.14191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/05/2023] [Accepted: 05/24/2023] [Indexed: 06/22/2023]
Abstract
In many species, the order in which males mate with a female explains much of the variation in paternity arising from post-copulatory sexual selection. Research in Drosophila suggests that mating order may account for the majority of the variance in male reproductive success. However, the effects of mating order on paternity bias might not be static but could potentially vary with social or environmental factors. To test this idea, we used an existing dataset, collated from an experiment we previously published (Morimoto et al., PLoS One, 11, 2016, e0154468), with the addition of unpublished data from the same experiment. These previous experiments manipulated larval density in Drosophila melanogaster which generated variation in male and female body size, assembled groups of individuals of different sizes, and measured the mating success and paternity share of focal males. The data presented here provides information on each focal male's mating order and the frequency in which focal males remated with same females ('repetitive matings'). We combined this information with our previously reported focal male reproductive success to partition variance in paternity into male mating order and repetitive matings across groups that differed in the body size composition of males and females. We found, as expected, that male mating order explained a considerable portion of the variance in male paternity. However, we also found that the impact of male mating order on male paternity was influenced by the body size composition of groups. Specifically, males that tended to mate last had a greater paternity advantage, and displayed lower variance, in groups containing a heterogenous mixture male body sizes than in groups with a single male body size. Repetitive mating only had a minor contribution to the variance in male paternity share across all experiments. Overall, our findings contribute to the growing body of research showing that post-copulatory sexual selection is subject to socio-ecological influences.
Collapse
Affiliation(s)
- Juliano Morimoto
- School of Biological SciencesUniversity of AberdeenAberdeenUK
- Programa de Pós‐graduação em Ecologia e ConservaçãoUniversidade Federal do ParanáCuritibaBrazil
- Institute of MathematicsUniversity of Aberdeen, King's CollegeAberdeenUK
| | - Grant C. McDonald
- Department of EcologyUniversity of Veterinary Medicine BudapestBudapestHungary
| | - Stuart Wigby
- Department of Evolution, Ecology, and Behaviour, Institute of Infection, Veterinary & Ecological SciencesUniversity of LiverpoolLiverpoolUK
| |
Collapse
|
7
|
Nguyen THM, Tinz-Burdick A, Lenhardt M, Geertz M, Ramirez F, Schwartz M, Toledano M, Bonney B, Gaebler B, Liu W, Wolters JF, Chiu K, Fiumera AC, Fiumera HL. Mapping mitonuclear epistasis using a novel recombinant yeast population. PLoS Genet 2023; 19:e1010401. [PMID: 36989278 PMCID: PMC10085025 DOI: 10.1371/journal.pgen.1010401] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 04/10/2023] [Accepted: 03/10/2023] [Indexed: 03/30/2023] Open
Abstract
Genetic variation in mitochondrial and nuclear genomes can perturb mitonuclear interactions and lead to phenotypic differences between individuals and populations. Despite their importance to most complex traits, it has been difficult to identify the interacting mitonuclear loci. Here, we present a novel advanced intercrossed population of Saccharomyces cerevisiae yeasts, called the Mitonuclear Recombinant Collection (MNRC), designed explicitly for detecting mitonuclear loci contributing to complex traits. For validation, we focused on mapping genes that contribute to the spontaneous loss of mitochondrial DNA (mtDNA) that leads to the petite phenotype in yeast. We found that rates of petite formation in natural populations are variable and influenced by genetic variation in nuclear DNA, mtDNA and mitonuclear interactions. We mapped nuclear and mitonuclear alleles contributing to mtDNA stability using the MNRC by integrating a term for mitonuclear epistasis into a genome-wide association model. We found that the associated mitonuclear loci play roles in mitotic growth most likely responding to retrograde signals from mitochondria, while the associated nuclear loci with main effects are involved in genome replication. We observed a positive correlation between growth rates and petite frequencies, suggesting a fitness tradeoff between mitotic growth and mtDNA stability. We also found that mtDNA stability was correlated with a mobile mitochondrial GC-cluster that is present in certain populations of yeast and that selection for nuclear alleles that stabilize mtDNA may be rapidly occurring. The MNRC provides a powerful tool for identifying mitonuclear interacting loci that will help us to better understand genotype-phenotype relationships and coevolutionary trajectories.
Collapse
Affiliation(s)
- Tuc H M Nguyen
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
- Department of Biological Sciences, New York University, New York, New York, United States of America
| | - Austen Tinz-Burdick
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Meghan Lenhardt
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Margaret Geertz
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Franchesca Ramirez
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Mark Schwartz
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Michael Toledano
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Brooke Bonney
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Benjamin Gaebler
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Weiwei Liu
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - John F Wolters
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Kenneth Chiu
- Department of Computer Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Heather L Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| |
Collapse
|
8
|
Fricke C, Sanghvi K, Emery M, Lindenbaum I, Wigby S, Ramm SA, Sepil I. Timeless or tainted? The effects of male ageing on seminal fluid. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1066022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Reproductive ageing can occur due to the deterioration of both the soma and germline. In males, it has mostly been studied with respect to age-related changes in sperm. However, the somatic component of the ejaculate, seminal fluid, is also essential for maintaining reproductive function. Whilst we know that seminal fluid proteins (SFPs) are required for male reproductive success across diverse taxa, age-related changes in SFP quantity and composition are little understood. Additionally, only few studies have explored the reproductive ageing of the tissues that produce SFPs, and the resulting reproductive outcomes. Here we provide a systematic review of studies addressing how advancing male age affects the production and properties of seminal fluid, in particular SFPs and oxidative stress, highlighting many open questions and generating new hypotheses for further research. We additionally discuss how declines in function of different components of seminal fluid, such as SFPs and antioxidants, could contribute to age-related loss of reproductive ability. Overall, we find evidence that ageing results in increased oxidative stress in seminal fluid and a decrease in the abundance of various SFPs. These results suggest that seminal fluid contributes towards important age-related changes influencing male reproduction. Thus, it is essential to study this mostly ignored component of the ejaculate to understand male reproductive ageing, and its consequences for sexual selection and paternal age effects on offspring.
Collapse
|
9
|
Corbel Q, Londoño‐Nieto C, Carazo P. Does perception of female cues modulate male short-term fitness components in Drosophila melanogaster? Ecol Evol 2022; 12:e9287. [PMID: 36177144 PMCID: PMC9471061 DOI: 10.1002/ece3.9287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 08/08/2022] [Accepted: 08/18/2022] [Indexed: 11/28/2022] Open
Abstract
Phenotypic plasticity in reproductive behavior can be a strong driver of individual fitness. In species with high intra-sexual competition, changes in socio-sexual context can trigger quick adaptive plastic responses in males. In particular, a recent study in the vinegar fly (Drosophila melanogaster) shows that males derive net fitness benefits from being shortly exposed to female cues ahead of access to mating (termed sexual perception), but the underlying mechanisms of this phenomenon remain unknown. Here, we investigated the short-term effects of female perception on male pre- and post-copulatory components of reproductive performance: (a) mating success, (b) mating latency and duration, (c) sperm competitiveness, and (d) ejaculate effects on female receptivity and reproductive rate. We found that brief sexual perception increased mating duration, but had no effect on the other main pre- and post-copulatory fitness proxies recorded. This suggests that perception of female cues may not yield net fitness benefits for males in the short-term, but we discuss alternative explanations and future avenues of research.
Collapse
Affiliation(s)
- Quentin Corbel
- Ethology Lab, Ethology, Ecology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| | - Claudia Londoño‐Nieto
- Ethology Lab, Ethology, Ecology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| | - Pau Carazo
- Ethology Lab, Ethology, Ecology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| |
Collapse
|
10
|
Chen DS, Clark AG, Wolfner MF. Octopaminergic/tyraminergic Tdc2 neurons regulate biased sperm usage in female Drosophila melanogaster. Genetics 2022; 221:6637517. [PMID: 35809068 PMCID: PMC9339280 DOI: 10.1093/genetics/iyac096] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 06/07/2022] [Indexed: 02/07/2023] Open
Abstract
In polyandrous internally fertilizing species, a multiply-mated female can use stored sperm from different males in a biased manner to fertilize her eggs. The female's ability to assess sperm quality and compatibility is essential for her reproductive success, and represents an important aspect of postcopulatory sexual selection. In Drosophila melanogaster, previous studies demonstrated that the female nervous system plays an active role in influencing progeny paternity proportion, and suggested a role for octopaminergic/tyraminergic Tdc2 neurons in this process. Here, we report that inhibiting Tdc2 neuronal activity causes females to produce a higher-than-normal proportion of first-male progeny. This difference is not due to differences in sperm storage or release, but instead is attributable to the suppression of second-male sperm usage bias that normally occurs in control females. We further show that a subset of Tdc2 neurons innervating the female reproductive tract is largely responsible for the progeny proportion phenotype that is observed when Tdc2 neurons are inhibited globally. On the contrary, overactivation of Tdc2 neurons does not further affect sperm storage, release or progeny proportion. These results suggest that octopaminergic/tyraminergic signaling allows a multiply-mated female to bias sperm usage, and identify a new role for the female nervous system in postcopulatory sexual selection.
Collapse
Affiliation(s)
- Dawn S Chen
- Department of Molecular Biology and Genetics, Cornell University, Ithaca NY 14853, USA
| | - Andrew G Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca NY 14853, USA
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca NY 14853, USA
| |
Collapse
|
11
|
Patlar B, Civetta A. Seminal fluid gene expression and reproductive fitness in Drosophila melanogaster. BMC Ecol Evol 2022; 22:20. [PMID: 35196983 PMCID: PMC8867848 DOI: 10.1186/s12862-022-01975-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 02/15/2022] [Indexed: 11/24/2022] Open
Abstract
Background The rapid evolution of seminal fluid proteins (SFPs) has been suggested to be driven by adaptations to postcopulatory sexual selection (e.g. sperm competition). However, we have recently shown that most SFPs evolve rapidly under relaxed selective pressures. Given the role of SFPs in competition for fertilization phenotypes, like the ability to transfer and store sperm and the modulation of female receptivity and ovulation, the prevalence of selectively relaxed SFPs appears as a conundrum. One possible explanation is that selection on SFPs might be relaxed in terms of protein amino acid content, but adjustments of expression are essential for post-mating function. Interestingly, there is a general lack of systematic implementation of gene expression perturbation assays to monitor their effect on phenotypes related to sperm competition. Results We successfully manipulated the expression of 16 SFP encoding genes using tissue-specific knockdowns (KDs) and determined the effect of these genes’ perturbation on three important post-mating phenotypes: female refractoriness to remating, defensive (P1), and offensive (P2) sperm competitive abilities in Drosophila melanogaster. Our analyses show that KDs of tested SFP genes do not affect female refractoriness to remating and P2, however, most gene KDs significantly decreased P1. Moreover, KDs of SFP genes that are selectively constrained in terms of protein-coding sequence evolution have lower P1 than KDs of genes evolving under relaxed selection. Conclusions Our results suggest a more predominant role, than previously acknowledged, of variation in gene expression than coding sequence changes on sperm competitive ability in D. melanogaster. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-022-01975-1.
Collapse
Affiliation(s)
- Bahar Patlar
- Department of Biology, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada
| | - Alberto Civetta
- Department of Biology, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada.
| |
Collapse
|
12
|
Majane AC, Cridland JM, Begun DJ. Single-nucleus transcriptomes reveal evolutionary and functional properties of cell types in the Drosophila accessory gland. Genetics 2022; 220:iyab213. [PMID: 34849871 PMCID: PMC9097260 DOI: 10.1093/genetics/iyab213] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/10/2021] [Indexed: 11/14/2022] Open
Abstract
Many traits responsible for male reproduction evolve quickly, including gene expression phenotypes in germline and somatic male reproductive tissues. Rapid male evolution in polyandrous species is thought to be driven by competition among males for fertilizations and conflicts between male and female fitness interests that manifest in postcopulatory phenotypes. In Drosophila, seminal fluid proteins secreted by three major cell types of the male accessory gland and ejaculatory duct are required for female sperm storage and use, and influence female postcopulatory traits. Recent work has shown that these cell types have overlapping but distinct effects on female postcopulatory biology, yet relatively little is known about their evolutionary properties. Here, we use single-nucleus RNA-Seq of the accessory gland and ejaculatory duct from Drosophila melanogaster and two closely related species to comprehensively describe the cell diversity of these tissues and their transcriptome evolution for the first time. We find that seminal fluid transcripts are strongly partitioned across the major cell types, and expression of many other genes additionally defines each cell type. We also report previously undocumented diversity in main cells. Transcriptome divergence was found to be heterogeneous across cell types and lineages, revealing a complex evolutionary process. Furthermore, protein adaptation varied across cell types, with potential consequences for our understanding of selection on male postcopulatory traits.
Collapse
Affiliation(s)
- Alex C Majane
- Department of Evolution and Ecology, University of California – Davis, Davis, CA 95616, USA
| | - Julie M Cridland
- Department of Evolution and Ecology, University of California – Davis, Davis, CA 95616, USA
| | - David J Begun
- Department of Evolution and Ecology, University of California – Davis, Davis, CA 95616, USA
| |
Collapse
|
13
|
Savini G, Scolari F, Ometto L, Rota-Stabelli O, Carraretto D, Gomulski LM, Gasperi G, Abd-Alla AMM, Aksoy S, Attardo GM, Malacrida AR. Viviparity and habitat restrictions may influence the evolution of male reproductive genes in tsetse fly (Glossina) species. BMC Biol 2021; 19:211. [PMID: 34556101 PMCID: PMC8461966 DOI: 10.1186/s12915-021-01148-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 09/06/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Glossina species (tsetse flies), the sole vectors of African trypanosomes, maintained along their long evolutionary history a unique reproductive strategy, adenotrophic viviparity. Viviparity reduces their reproductive rate and, as such, imposes strong selective pressures on males for reproductive success. These species live in sub-Saharan Africa, where the distributions of the main sub-genera Fusca, Morsitans, and Palpalis are restricted to forest, savannah, and riverine habitats, respectively. Here we aim at identifying the evolutionary patterns of the male reproductive genes of six species belonging to these three main sub-genera. We then interpreted the different patterns we found across the species in the light of viviparity and the specific habitat restrictions, which are known to shape reproductive behavior. RESULTS We used a comparative genomic approach to build consensus evolutionary trees that portray the selective pressure acting on the male reproductive genes in these lineages. Such trees reflect the long and divergent demographic history that led to an allopatric distribution of the Fusca, Morsitans, and Palpalis species groups. A dataset of over 1700 male reproductive genes remained conserved over the long evolutionary time scale (estimated at 26.7 million years) across the genomes of the six species. We suggest that this conservation may result from strong functional selective pressure on the male imposed by viviparity. It is noteworthy that more than half of these conserved genes are novel sequences that are unique to the Glossina genus and are candidates for selection in the different lineages. CONCLUSIONS Tsetse flies represent a model to interpret the evolution and differentiation of male reproductive biology under different, but complementary, perspectives. In the light of viviparity, we must take into account that these genes are constrained by a post-fertilization arena for genomic conflicts created by viviparity and absent in ovipositing species. This constraint implies a continuous antagonistic co-evolution between the parental genomes, thus accelerating inter-population post-zygotic isolation and, ultimately, favoring speciation. Ecological restrictions that affect reproductive behavior may further shape such antagonistic co-evolution.
Collapse
Affiliation(s)
- Grazia Savini
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
- Institute of Molecular Genetics IGM-CNR "Luigi Luca Cavalli-Sforza", Pavia, Italy
| | - Lino Ometto
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Omar Rota-Stabelli
- Research and Innovation Centre, Fondazione Edmund Mach (FEM), San Michele all'Adige, Italy
- Center Agriculture Food Environment (C3A), University of Trento, Trento, Italy
| | - Davide Carraretto
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Ludvik M Gomulski
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Adly M M Abd-Alla
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food & Agriculture, Vienna, Vienna, Austria.
| | - Serap Aksoy
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Geoffrey M Attardo
- Department of Entomology and Nematology, University of California, Davis, Davis, CA, USA
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
| |
Collapse
|
14
|
Patlar B, Jayaswal V, Ranz JM, Civetta A. Nonadaptive molecular evolution of seminal fluid proteins in Drosophila. Evolution 2021; 75:2102-2113. [PMID: 34184267 PMCID: PMC8457112 DOI: 10.1111/evo.14297] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/02/2021] [Accepted: 06/09/2021] [Indexed: 12/20/2022]
Abstract
Seminal fluid proteins (SFPs) are a group of reproductive proteins that are among the most evolutionarily divergent known. As SFPs can impact male and female fitness, these proteins have been proposed to evolve under postcopulatory sexual selection (PCSS). However, the fast change of the SFPs can also result from nonadaptive evolution, and the extent to which selective constraints prevent SFPs rapid evolution remains unknown. Using intra‐ and interspecific sequence information, along with genomics and functional data, we examine the molecular evolution of approximately 300 SFPs in Drosophila. We found that 50–57% of the SFP genes, depending on the population examined, are evolving under relaxed selection. Only 7–12% showed evidence of positive selection, with no evidence supporting other forms of PCSS, and 35–37% of the SFP genes were selectively constrained. Further, despite associations of positive selection with gene location on the X chromosome and protease activity, the analysis of additional genomic and functional features revealed their lack of influence on SFPs evolving under positive selection. Our results highlight a lack of sufficient evidence to claim that most SFPs are driven to evolve rapidly by PCSS while identifying genomic and functional attributes that influence different modes of SFPs evolution.
Collapse
Affiliation(s)
- Bahar Patlar
- Department of Biology, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada
| | - Vivek Jayaswal
- School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, 2006, Australia
| | - José M Ranz
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, California, 92697
| | - Alberto Civetta
- Department of Biology, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada
| |
Collapse
|
15
|
Lovejoy PC, Foley KE, Conti MM, Meadows SM, Bishop C, Fiumera AC. Genetic basis of susceptibility to low-dose paraquat and variation between the sexes in Drosophila melanogaster. Mol Ecol 2021; 30:2040-2053. [PMID: 33710693 DOI: 10.1111/mec.15878] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 02/23/2021] [Indexed: 12/18/2022]
Abstract
Toxicant resistance is a complex trait, affected both by genetics and the environment. Like most complex traits, it can exhibit sexual dimorphism, yet sex is often overlooked as a factor in studies of toxicant resistance. Paraquat, one such toxicant, is a commonly used herbicide and is known to produce mitochondrial oxidative stress, decrease dopaminergic neurons and dopamine (DA) levels, and decrease motor ability. While the main effects of paraquat are well-characterized, less is known about the naturally occurring variation in paraquat susceptibility. The purpose of this study was to map the genes contributing to low-dose paraquat susceptibility in Drosophila melanogaster, and to determine if susceptibility differs between the sexes. One hundred of the Drosophila Genetic Reference Panel (DGRP) lines were scored for susceptibility via climbing ability and used in a genome-wide association study (GWAS). Variation in seventeen genes in females and thirty-five genes in males associated with paraquat susceptibility. Only two candidate genes overlapped between the sexes despite a significant positive correlation between male and female susceptibilities. Many associated polymorphisms had significant interactions with sex, with most having conditionally neutral effects. Conditional neutrality between the sexes probably stems from sex-biased expression which may result from partial resolution of sexual conflict. Candidate genes were verified with RNAi knockdowns, gene expression analyses, and DA quantification. Several of these genes are novel associations with paraquat susceptibility. This research highlights the importance of assessing both sexes when studying toxicant susceptibility.
Collapse
Affiliation(s)
- Pamela C Lovejoy
- Department of Biological Sciences, Binghamton University, Binghamton, NY, USA.,Department of Biology, St. Joseph's College, Brooklyn, NY, USA
| | - Kate E Foley
- Department of Biological Sciences, Binghamton University, Binghamton, NY, USA
| | - Melissa M Conti
- Department of Psychology, Binghamton University, Binghamton, NY, USA
| | | | | | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, NY, USA
| |
Collapse
|
16
|
Brandies PA, Wright BR, Hogg CJ, Grueber CE, Belov K. Characterization of reproductive gene diversity in the endangered Tasmanian devil. Mol Ecol Resour 2020; 21:721-732. [PMID: 33188658 DOI: 10.1111/1755-0998.13295] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/25/2020] [Accepted: 11/05/2020] [Indexed: 01/11/2023]
Abstract
Interindividual variation at genes known to play a role in reproduction may impact reproductive fitness. The Tasmanian devil is an endangered Australian marsupial with low genetic diversity. Recent work has shown concerning declines in productivity in both wild and captive populations over time. Understanding whether functional diversity exists at reproductive genes in the Tasmanian devil is a key first step in identifying genes that may influence productivity. We characterized single nucleotide polymorphisms (SNPs) at 214 genes involved in reproduction in 37 Tasmanian devils. Twenty genes contained nonsynonymous substitutions, with genes involved in embryogenesis, fertilization and hormonal regulation of reproduction displaying greater numbers of nonsynonymous SNPs than synonymous SNPs. Two genes, ADAMTS9 and NANOG, showed putative signatures of balancing selection indicating that natural selection is maintaining diversity at these genes despite the species exhibiting low overall levels of genetic diversity. We will use this information in future to examine the interplay between reproductive gene variation and reproductive fitness in Tasmanian devil populations.
Collapse
Affiliation(s)
- Parice A Brandies
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia
| | - Belinda R Wright
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia
| | - Carolyn J Hogg
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia
| | - Catherine E Grueber
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia.,San Diego Zoo Global, San Diego, CA, USA
| | - Katherine Belov
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia
| |
Collapse
|
17
|
Wigby S, Brown NC, Allen SE, Misra S, Sitnik JL, Sepil I, Clark AG, Wolfner MF. The Drosophila seminal proteome and its role in postcopulatory sexual selection. Philos Trans R Soc Lond B Biol Sci 2020; 375:20200072. [PMID: 33070726 DOI: 10.1098/rstb.2020.0072] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Postcopulatory sexual selection (PCSS), comprised of sperm competition and cryptic female choice, has emerged as a widespread evolutionary force among polyandrous animals. There is abundant evidence that PCSS can shape the evolution of sperm. However, sperm are not the whole story: they are accompanied by seminal fluid substances that play many roles, including influencing PCSS. Foremost among seminal fluid models is Drosophila melanogaster, which displays ubiquitous polyandry, and exhibits intraspecific variation in a number of seminal fluid proteins (Sfps) that appear to modulate paternity share. Here, we first consolidate current information on the identities of D. melanogaster Sfps. Comparing between D. melanogaster and human seminal proteomes, we find evidence of similarities between many protein classes and individual proteins, including some D. melanogaster Sfp genes linked to PCSS, suggesting evolutionary conservation of broad-scale functions. We then review experimental evidence for the functions of D. melanogaster Sfps in PCSS and sexual conflict. We identify gaps in our current knowledge and areas for future research, including an enhanced identification of PCSS-related Sfps, their interactions with rival sperm and with females, the role of qualitative changes in Sfps and mechanisms of ejaculate tailoring. This article is part of the theme issue 'Fifty years of sperm competition'.
Collapse
Affiliation(s)
- Stuart Wigby
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L69 7ZB, UK.,Faculty Biology, Applied Zoology, Technische Universität Dresden, 01069 Dresden, Germany
| | - Nora C Brown
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Sarah E Allen
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Snigdha Misra
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Jessica L Sitnik
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Irem Sepil
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Andrew G Clark
- 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
| |
Collapse
|
18
|
Lüpold S, Reil JB, Manier MK, Zeender V, Belote JM, Pitnick S. How female × male and male × male interactions influence competitive fertilization in Drosophila melanogaster. Evol Lett 2020; 4:416-429. [PMID: 33014418 PMCID: PMC7523561 DOI: 10.1002/evl3.193] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/02/2020] [Accepted: 08/13/2020] [Indexed: 01/01/2023] Open
Abstract
How males and females contribute to joint reproductive success has been a long‐standing question in sexual selection. Under postcopulatory sexual selection, paternity success is predicted to derive from complex interactions among females engaging in cryptic female choice and males engaging in sperm competition. Such interactions have been identified as potential sources of genetic variation in sexually selected traits but are also expected to inhibit trait diversification. To date, studies of interactions between females and competing males have focused almost exclusively on genotypes and not phenotypic variation in sexually selected traits. Here, we characterize within‐ and between‐sex interactions in Drosophila melanogaster using isogenic lines with heritable variation in both male and female traits known to influence competitive fertilization. We confirmed, and expanded on, previously reported genotypic interactions within and between the sexes, and showed that several reproductive events, including sperm transfer, female sperm ejection, and sperm storage, were explained by two‐ and three‐way interactions among sex‐specific phenotypes. We also documented complex interactions between the lengths of competing males’ sperm and the female seminal receptacle, which are known to have experienced rapid female‐male co‐diversification. Our results highlight the nonindependence of sperm competition and cryptic female choice and demonstrate that complex interactions between the sexes do not limit the ability of multivariate systems to respond to directional sexual selection.
Collapse
Affiliation(s)
- Stefan Lüpold
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH-8057 Switzerland.,Department of Biology Syracuse University Syracuse New York 13244
| | - Jonathan Bradley Reil
- Department of Entomology Cornell University Ithaca New York 14853.,Department of Plant and Environmental Protection Sciences University of Hawaii at Mānoa Honolulu Hawaii 96822
| | - Mollie K Manier
- Department of Biology Syracuse University Syracuse New York 13244.,Department of Biological Sciences George Washington University Washington DC 20052
| | - Valérian Zeender
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH-8057 Switzerland
| | - John M Belote
- Department of Biology Syracuse University Syracuse New York 13244
| | - Scott Pitnick
- Department of Biology Syracuse University Syracuse New York 13244
| |
Collapse
|
19
|
Nakadera Y, Thornton Smith A, Daupagne L, Coutellec MA, Koene JM, Ramm SA. Divergence of seminal fluid gene expression and function among natural snail populations. J Evol Biol 2020; 33:1440-1451. [PMID: 32697880 DOI: 10.1111/jeb.13683] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/03/2020] [Accepted: 07/09/2020] [Indexed: 12/29/2022]
Abstract
Seminal fluid proteins (SFPs) can trigger drastic changes in mating partners, mediating post-mating sexual selection and associated sexual conflict. Also, cross-species comparisons have demonstrated that SFPs evolve rapidly and hint that post-mating sexual selection drives their rapid evolution. In principle, this pattern should be detectable within species as rapid among-population divergence in SFP expression and function. However, given the multiple other factors that could vary among populations, isolating divergence in SFP-mediated effects is not straightforward. Here, we attempted to address this gap by combining the power of a common garden design with functional assays involving artificial injection of SFPs in the simultaneously hermaphroditic freshwater snail, Lymnaea stagnalis. We detected among-population divergence in SFP gene expression, suggesting that seminal fluid composition differs among four populations collected in Western Europe. Furthermore, by artificially injecting seminal fluid extracted from these field-derived snails into standardized mating partners, we also detected among-population divergence in the strength of post-mating effects induced by seminal fluid. Both egg production and subsequent sperm transfer of partners differed depending on the population origin of seminal fluid, with the response in egg production seemingly closely corresponding to among-population divergence in SFP gene expression. Our results thus lend strong intraspecific support to the notion that SFP expression and function evolve rapidly, and confirm L. stagnalis as an amenable system for studying processes driving SFP evolution.
Collapse
Affiliation(s)
- Yumi Nakadera
- Evolutionary Biology, Bielefeld University, Bielefeld, Germany.,Ecological Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Léa Daupagne
- Ecological Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Joris M Koene
- Ecological Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Steven A Ramm
- Evolutionary Biology, Bielefeld University, Bielefeld, Germany
| |
Collapse
|
20
|
McCullough EL, McDonough CE, Pitnick S, Dorus S. Quantitative proteomics reveals rapid divergence in the postmating response of female reproductive tracts among sibling species. Proc Biol Sci 2020; 287:20201030. [PMID: 32576111 DOI: 10.1098/rspb.2020.1030] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Fertility depends, in part, on interactions between male and female reproductive proteins inside the female reproductive tract (FRT) that mediate postmating changes in female behaviour, morphology, and physiology. Coevolution between interacting proteins within species may drive reproductive incompatibilities between species, yet the mechanisms underlying postmating-prezygotic (PMPZ) isolating barriers remain poorly resolved. Here, we used quantitative proteomics in sibling Drosophila species to investigate the molecular composition of the FRT environment and its role in mediating species-specific postmating responses. We found that (i) FRT proteomes in D. simulans and D. mauritiana virgin females express unique combinations of secreted proteins and are enriched for distinct functional categories, (ii) mating induces substantial changes to the FRT proteome in D. mauritiana but not in D. simulans, and (iii) the D. simulans FRT proteome exhibits limited postmating changes irrespective of whether females mate with conspecific or heterospecific males, suggesting an active female role in mediating reproductive interactions. Comparisons with similar data in the closely related outgroup species D. melanogaster suggest that divergence is concentrated on the D. simulans lineage. Our study suggests that divergence in the FRT extracellular environment and postmating response contribute to previously described patterns of PMPZ isolation and the maintenance of species boundaries.
Collapse
Affiliation(s)
- Erin L McCullough
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| | - Caitlin E McDonough
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| | - Scott Pitnick
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| | - Steve Dorus
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| |
Collapse
|
21
|
Weber M, Giannakara A, Ramm SA. Seminal fluid-mediated fitness effects in the simultaneously hermaphroditic flatworm Macrostomum lignano. Ecol Evol 2019; 9:13889-13901. [PMID: 31938489 PMCID: PMC6953679 DOI: 10.1002/ece3.5825] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 11/08/2022] Open
Abstract
As a class, seminal fluid proteins are expected to exert strong effects on mating partners due to the selection pressures of sperm competition and sexual conflict. But because of the complexity of this secretion, linking specific proteins to downstream effects on own fitness-via manipulating the reproductive behavior, physiology, and ultimately the sperm utilization of mating partners-is not straightforward. Here, we adopted a systematic gene knockdown approach to screen for seminal fluid-mediated fitness effects in the simultaneously hermaphroditic flatworm Macrostomum lignano. We focused on 18 transcripts in M. lignano seminal fluid, testing how their RNA interference-induced knockdown impacted on three aspects of donor (male) reproductive success: (a) fertility (offspring production of the partner); (b) defensive sperm competitive ability, P 1; and (c) offensive sperm competitive ability, P 2. In general, the knockdown of most individual transcripts appeared to have only a minor impact on male reproductive success, though we found evidence that the knockdown of up to five different transcripts impacted on fertility; the knockdown of two other transcripts resulted in reduced P 2; and knockdown of a further transcript actually increased P 2. We thus identify a number of candidate seminal fluid transcripts that appear to modulate offspring production and sperm competitiveness in M. lignano. That only a minority of transcripts exhibit such a pattern likely reflects both the difficulty of accurately estimating sperm competitiveness and the functional redundancy of seminal fluid.
Collapse
Affiliation(s)
- Michael Weber
- Department of Evolutionary BiologyBielefeld UniversityBielefeldGermany
| | - Athina Giannakara
- Department of Evolutionary BiologyBielefeld UniversityBielefeldGermany
| | - Steven A. Ramm
- Department of Evolutionary BiologyBielefeld UniversityBielefeldGermany
| |
Collapse
|
22
|
Patlar B, Ramm SA. Genotype‐by‐environment interactions for seminal fluid expression and sperm competitive ability. J Evol Biol 2019; 33:225-236. [DOI: 10.1111/jeb.13568] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/25/2019] [Accepted: 11/06/2019] [Indexed: 12/01/2022]
Affiliation(s)
- Bahar Patlar
- Evolutionary Biology Bielefeld University Bielefeld Germany
| | - Steven A. Ramm
- Evolutionary Biology Bielefeld University Bielefeld Germany
| |
Collapse
|
23
|
BMP signaling inhibition in Drosophila secondary cells remodels the seminal proteome and self and rival ejaculate functions. Proc Natl Acad Sci U S A 2019; 116:24719-24728. [PMID: 31740617 PMCID: PMC6900634 DOI: 10.1073/pnas.1914491116] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Seminal fluid proteins (SFPs) exert potent effects on male and female fitness. Rapidly evolving and molecularly diverse, they derive from multiple male secretory cells and tissues. In Drosophila melanogaster, most SFPs are produced in the accessory glands, which are composed of ∼1,000 fertility-enhancing "main cells" and ∼40 more functionally cryptic "secondary cells." Inhibition of bone morphogenetic protein (BMP) signaling in secondary cells suppresses secretion, leading to a unique uncoupling of normal female postmating responses to the ejaculate: refractoriness stimulation is impaired, but offspring production is not. Secondary-cell secretions might therefore make highly specific contributions to the seminal proteome and ejaculate function; alternatively, they might regulate more global-but hitherto undiscovered-SFP functions and proteome composition. Here, we present data that support the latter model. We show that in addition to previously reported phenotypes, secondary-cell-specific BMP signaling inhibition compromises sperm storage and increases female sperm use efficiency. It also impacts second male sperm, tending to slow entry into storage and delay ejection. First male paternity is enhanced, which suggests a constraint on ejaculate evolution whereby high female refractoriness and sperm competitiveness are mutually exclusive. Using quantitative proteomics, we reveal changes to the seminal proteome that surprisingly encompass alterations to main-cell-derived proteins, indicating important cross-talk between classes of SFP-secreting cells. Our results demonstrate that ejaculate composition and function emerge from the integrated action of multiple secretory cell types, suggesting that modification to the cellular make-up of seminal-fluid-producing tissues is an important factor in ejaculate evolution.
Collapse
|
24
|
Rodriguez‐Exposito E, Garcia‐Gonzalez F, Polak M. Individual and synergistic effects of male external genital traits in sexual selection. J Evol Biol 2019; 33:67-79. [DOI: 10.1111/jeb.13546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/15/2019] [Accepted: 09/19/2019] [Indexed: 01/22/2023]
Affiliation(s)
| | - Francisco Garcia‐Gonzalez
- Doñana Biological Station (CSIC) Sevilla Spain
- Centre for Evolutionary Biology School of Biological Sciences The University of Western Australia Crawley WA Australia
| | - Michal Polak
- Department of Biological Sciences University of Cincinnati Cincinnati OH USA
| |
Collapse
|
25
|
Civetta A, Ranz JM. Genetic Factors Influencing Sperm Competition. Front Genet 2019; 10:820. [PMID: 31572439 PMCID: PMC6753916 DOI: 10.3389/fgene.2019.00820] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/08/2019] [Indexed: 12/26/2022] Open
Abstract
Females of many different species often mate with multiple males, creating opportunities for competition among their sperm. Although originally unappreciated, sperm competition is now considered a central form of post-copulatory male–male competition that biases fertilization. Assays of differences in sperm competitive ability between males, and interactions between females and males, have made it possible to infer some of the main mechanisms of sperm competition. Nevertheless, classical genetic approaches have encountered difficulties in identifying loci influencing sperm competitiveness while functional and comparative genomic methodologies, as well as genetic variant association studies, have uncovered some interesting candidate genes. We highlight how the systematic implementation of approaches that incorporate gene perturbation assays in experimental competitive settings, together with the monitoring of progeny output or sperm features and behavior, has allowed the identification of genes unambiguously linked to sperm competitiveness. The emerging portrait from 45 genes (33 from fruit flies, 8 from rodents, 2 from nematodes, and 2 from ants) is their remarkable breadth of biological roles exerted through males and females, the non-preponderance of sperm genes, and their overall pleiotropic nature.
Collapse
Affiliation(s)
- Alberto Civetta
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
| | - José M Ranz
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, United States
| |
Collapse
|
26
|
Divergent allocation of sperm and the seminal proteome along a competition gradient in Drosophila melanogaster. Proc Natl Acad Sci U S A 2019; 116:17925-17933. [PMID: 31431535 PMCID: PMC6731677 DOI: 10.1073/pnas.1906149116] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Ejaculate quality plays an essential role in fertility, sperm competition, and offspring health. A key modulator of ejaculate quality is the social environment. Although males across taxa are known to strategically allocate sperm in response to rivals, how this applies to myriad other ejaculate components is poorly resolved. Here, we take a multilevel approach, from protein to fitness, to show that Drosophila melanogaster males divergently allocate sperm and seminal fluid proteins along a competition gradient. Using a combination of fluorescence-labeled sperm, quantitative proteomics, and multimating assays, we demonstrate that males are remarkably sensitive to the intensity of competition they perceive, show compositional change across and within portions of the ejaculate, and that this compositional change carries distinct costs and benefits. Sperm competition favors large, costly ejaculates, and theory predicts the evolution of allocation strategies that enable males to plastically tailor ejaculate expenditure to sperm competition threat. While greater sperm transfer in response to a perceived increase in the risk of sperm competition is well-supported, we have a poor understanding of whether males (i) respond to changes in perceived intensity of sperm competition, (ii) use the same allocation rules for sperm and seminal fluid, and (iii) experience changes in current and future reproductive performance as a result of ejaculate compositional changes. Combining quantitative proteomics with fluorescent sperm labeling, we show that Drosophila melanogaster males exercise independent control over the transfer of sperm and seminal fluid proteins (SFPs) under different levels of male–male competition. While sperm transfer peaks at low competition, consistent with some theoretical predictions based on sperm competition intensity, the abundance of transferred SFPs generally increases at high competition levels. However, we find that clusters of SFPs vary in the directionality and sensitivity of their response to competition, promoting compositional change in seminal fluid. By tracking the degree of decline in male mating probability and offspring production across successive matings, we provide evidence that ejaculate compositional change represents an adaptive response to current sperm competition, but one that comes at a cost to future mating performance. Our work reveals a previously unknown divergence in ejaculate component allocation rules, exposes downstream costs of elevated ejaculate investment, and ultimately suggests a central role for ejaculate compositional plasticity in sexual selection.
Collapse
|
27
|
Chen DS, Delbare SYN, White SL, Sitnik J, Chatterjee M, DoBell E, Weiss O, Clark AG, Wolfner MF. Female Genetic Contributions to Sperm Competition in Drosophila melanogaster. Genetics 2019; 212:789-800. [PMID: 31101677 PMCID: PMC6614900 DOI: 10.1534/genetics.119.302284] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 05/11/2019] [Indexed: 11/18/2022] Open
Abstract
In many species, sperm can remain viable in the reproductive tract of a female well beyond the typical interval to remating. This creates an opportunity for sperm from different males to compete for oocyte fertilization inside the female's reproductive tract. In Drosophila melanogaster, sperm characteristics and seminal fluid content affect male success in sperm competition. On the other hand, although genome-wide association studies (GWAS) have demonstrated that female genotype plays a role in sperm competition outcome as well, the biochemical, sensory, and physiological processes by which females detect and selectively use sperm from different males remain elusive. Here, we functionally tested 26 candidate genes implicated via a GWAS for their contribution to the female's role in sperm competition, measured as changes in the relative success of the first male to mate (P1). Of these 26 candidates, we identified eight genes that affect P1 when knocked down in females, and showed that five of them do so when knocked down in the female nervous system. In particular, Rim knockdown in sensory pickpocket (ppk)+ neurons lowered P1, confirming previously published results, and a novel candidate, caup, lowered P1 when knocked down in octopaminergic Tdc2+ neurons. These results demonstrate that specific neurons in the female's nervous system play a functional role in sperm competition and expand our understanding of the genetic, neuronal, and mechanistic basis of female responses to multiple matings. We propose that these neurons in females are used to sense, and integrate, signals from courtship or ejaculates, to modulate sperm competition outcome accordingly.
Collapse
Affiliation(s)
- Dawn S Chen
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Sofie Y N Delbare
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Simone L White
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Jessica Sitnik
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Martik Chatterjee
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Elizabeth DoBell
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Orli Weiss
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Andrew G Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853-2703
| |
Collapse
|
28
|
Patlar B, Weber M, Ramm SA. Genetic and environmental variation in transcriptional expression of seminal fluid proteins. Heredity (Edinb) 2019; 122:595-611. [PMID: 30356222 PMCID: PMC6461930 DOI: 10.1038/s41437-018-0160-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 08/29/2018] [Accepted: 09/18/2018] [Indexed: 12/31/2022] Open
Abstract
Seminal fluid proteins (SFPs) are crucial mediators of sexual selection and sexual conflict. Recent studies have chiefly focused on environmentally induced plasticity as one source of variation in SFP expression, particularly in response to differing sperm competition levels. However, understanding the evolution of a trait in heterogenous environments requires estimates of both environmental and genetic sources of variation, as well as their interaction. Therefore, we investigated how environment (specifically mating group size, a good predictor of sperm competition intensity), genotype and genotype-by-environment interactions affect seminal fluid expression. To do so, we reared 12 inbred lines of a simultaneously hermaphroditic flatworm Macrostomum lignano in groups of either two or eight worms and measured the expression levels of 58 putative SFP transcripts. We then examined the source of variation in the expression of each transcript individually and for multivariate axes extracted from a principal component analysis. We found that mating group size did not affect expression levels according to the single transcript analyses, nor did it affect the first principal component (presumably representing overall investment in seminal fluid production). However, mating group size did affect the relative expression of different transcripts captured by the second principal component (presumably reflecting variation in seminal fluid composition). Most transcripts were genetically variable in their expression level and several exhibited genotype-by-environment interactions; relative composition also showed high genetic variation. Collectively, our results reveal the tightly integrated nature of the seminal fluid transcriptome and provide new insights into the quantitative genetic basis of seminal fluid investment and composition.
Collapse
Affiliation(s)
- Bahar Patlar
- Evolutionary Biology, Bielefeld University, Bielefeld, Germany.
| | - Michael Weber
- Evolutionary Biology, Bielefeld University, Bielefeld, Germany
| | - Steven A Ramm
- Evolutionary Biology, Bielefeld University, Bielefeld, Germany
| |
Collapse
|
29
|
ECOVOIU ALEXANDRUAL, GRAUR MARIAN, RATIU ATTILACRISTIAN. Hypomorphic alleles of gammaCop gene from Drosophila melanogaster display an unexpected expression pattern in mutant eggs, testes and embryos. ROMANIAN BIOTECHNOLOGICAL LETTERS 2019. [DOI: 10.25083/rbl/24.2/324.331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
30
|
Sexual conflict drives male manipulation of female postmating responses in Drosophila melanogaster. Proc Natl Acad Sci U S A 2019; 116:8437-8444. [PMID: 30962372 PMCID: PMC6486729 DOI: 10.1073/pnas.1821386116] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In species with males and females, reproduction requires contributions from both sexes and therefore some degree of cooperation. At the same time, antagonistic interactions can evolve because of the differing goals of males and females. We aligned the interests of the sexes in the naturally promiscuous fruit fly Drosophila melanogaster by enforcing randomized monogamy for more than 150 generations. Males repeatedly evolved to manipulate females less, a pattern visible in both the timing of female reproductive effort and gene expression changes after mating. Male investment in expression of genes encoding seminal fluid proteins, which shape the female postmating response, declined concurrently. Our results confirm the presence of sexually antagonistic selection on postcopulatory interactions that can be reversed by monogamy. In many animals, females respond to mating with changes in physiology and behavior that are triggered by molecules transferred by males during mating. In Drosophila melanogaster, proteins in the seminal fluid are responsible for important female postmating responses, including temporal changes in egg production, elevated feeding rates and activity levels, reduced sexual receptivity, and activation of the immune system. It is unclear to what extent these changes are mutually beneficial to females and males or instead represent male manipulation. Here we use an experimental evolution approach in which females are randomly paired with a single male each generation, eliminating any opportunity for competition for mates or mate choice and thereby aligning the evolutionary interests of the sexes. After >150 generations of evolution, males from monogamous populations elicited a weaker postmating stimulation of egg production and activity than males from control populations that evolved with a polygamous mating system. Males from monogamous populations did not differ from males from polygamous populations in their ability to induce refractoriness to remating in females, but they were inferior to polygamous males in sperm competition. Mating-responsive genes in both the female abdomen and head showed a dampened response to mating with males from monogamous populations. Males from monogamous populations also exhibited lower expression of genes encoding seminal fluid proteins, which mediate the female response to mating. Together, these results demonstrate that the female postmating response, and the male molecules involved in eliciting this response, are shaped by ongoing sexual conflict.
Collapse
|
31
|
Nguyen TTX, Moehring AJ. A male's seminal fluid increases later competitors' productivity. J Evol Biol 2018; 31:1572-1581. [PMID: 30007107 DOI: 10.1111/jeb.13352] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 07/10/2018] [Accepted: 07/11/2018] [Indexed: 11/27/2022]
Abstract
Polyandrous females allow for sexual selection to persist after mating. In the event that females successfully mate with more than one male, sperm competition can occur. Seminal fluid proteins can indirectly affect a male's success in sperm competition through reducing the remating behaviour of females and can directly influence sperm competition through directly displacing competitor sperm or inducing females to eject it. These direct effects on competitor sperm are thought to contribute to the 'second male advantage', whereby the second male to mate sires the majority of offspring. Here, we show an additional mechanism where seminal proteins already present within a mated female appear to enhance offspring production of later competitor males, and contribute to second male advantage. Counter to expectation, increased offspring production was not due to a priming effect of greater early female productivity, nor was it through a general and consistent increase in offspring production. Instead, enhanced productivity was solely through lengthening the time that offspring are sired by the second male, indicating that seminal proteins from the first male to mate may enhance second male advantage through a presumably unintended protective effect on subsequent competitor sperm.
Collapse
|
32
|
Abstract
Sexual conflict is acknowledged as pervasive, with the potential to generate and maintain genetic variation. Mechanistic studies of conflict have been important in providing direct evidence for the existence of sexual conflict. They have also led to the growing realization that there is a striking phenotypic diversity of adaptations whose evolution can be shaped by sexually antagonistic selection. The mechanisms involved range from the use of genital spines, claspers, songs, and smells to ejaculate molecules. In one well-studied example, sexual conflict can occur over the sexually antagonistic effects of seminal fluid proteins in Drosophila melanogaster. However, an important puzzle remains, namely, why seminal fluid proteins are so numerous and complex, hence whether all or some are involved in mediating sexual conflict. I hypothesize that this rich diversity and the complexity of traits subject to sexually antagonistic selection in general may arise, at least in part, due to the deployment of sexually antagonistic adaptations in males in a way that lessens the probability of broadscale, strong resistance evolution in females. In elaborating this hypothesis, I explore how research into the evolution of resistance to insecticides, antimicrobials, and vaccines might be used to provide insights into the evolution of female resistance to the effects of sexually antagonistic manipulative traits of males. In this manner, the manipulative traits of males can be resistance-proofed.
Collapse
|
33
|
Delbare SYN, Chow CY, Wolfner MF, Clark AG. Roles of Female and Male Genotype in Post-Mating Responses in Drosophila melanogaster. J Hered 2018; 108:740-753. [PMID: 29036644 DOI: 10.1093/jhered/esx081] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 09/25/2017] [Indexed: 12/18/2022] Open
Abstract
Mating induces a multitude of changes in female behavior, physiology, and gene expression. Interactions between female and male genotype lead to variation in post-mating phenotypes and reproductive success. So far, few female molecules responsible for these interactions have been identified. Here, we used Drosophila melanogaster from 5 geographically dispersed populations to investigate such female × male genotypic interactions at the female transcriptomic and phenotypic levels. Females from each line were singly-mated to males from the same 5 lines, for a total of 25 combinations. Reproductive output and refractoriness to re-mating were assayed in females from the 25 mating combinations. Female × male genotypic interactions resulted in significant differences in these post-mating phenotypes. To assess whether female × male genotypic interactions affect the female post-mating transcriptome, next-generation RNA sequencing was performed on virgin and mated females at 5 to 6 h post-mating. Seventy-seven genes showed strong variation in mating-induced expression changes in a female × male genotype-dependent manner. These genes were enriched for immune response and odorant-binding functions, and for expression exclusively in the head. Strikingly, variation in post-mating transcript levels of a gene encoding a spermathecal endopeptidase was correlated with short-term egg production. The transcriptional variation found in specific functional classes of genes might be a read-out of female × male compatibility at a molecular level. Understanding the roles these genes play in the female post-mating response will be crucial to better understand the evolution of post-mating responses and related conflicts between the sexes.
Collapse
Affiliation(s)
- Sofie Y N Delbare
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703
| | - Clement Y Chow
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703.,Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703
| | - Andrew G Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703
| |
Collapse
|
34
|
Billeter JC, Wolfner MF. Chemical Cues that Guide Female Reproduction in Drosophila melanogaster. J Chem Ecol 2018; 44:750-769. [PMID: 29557077 DOI: 10.1007/s10886-018-0947-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Revised: 02/21/2018] [Accepted: 03/13/2018] [Indexed: 01/05/2023]
Abstract
Chemicals released into the environment by food, predators and conspecifics play critical roles in Drosophila reproduction. Females and males live in an environment full of smells, whose molecules communicate to them the availability of food, potential mates, competitors or predators. Volatile chemicals derived from fruit, yeast growing on the fruit, and flies already present on the fruit attract Drosophila, concentrating flies at food sites, where they will also mate. Species-specific cuticular hydrocarbons displayed on female Drosophila as they mature are sensed by males and act as pheromones to stimulate mating by conspecific males and inhibit heterospecific mating. The pheromonal profile of a female is also responsive to her nutritional environment, providing an honest signal of her fertility potential. After mating, cuticular and semen hydrocarbons transferred by the male change the female's chemical profile. These molecules make the female less attractive to other males, thus protecting her mate's sperm investment. Females have evolved the capacity to counteract this inhibition by ejecting the semen hydrocarbon (along with the rest of the remaining ejaculate) a few hours after mating. Although this ejection can temporarily restore the female's attractiveness, shortly thereafter another male pheromone, a seminal peptide, decreases the female's propensity to re-mate, thus continuing to protect the male's investment. Females use olfaction and taste sensing to select optimal egg-laying sites, integrating cues for the availability of food for her offspring, and the presence of other flies and of harmful species. We argue that taking into account evolutionary considerations such as sexual conflict, and the ecological conditions in which flies live, is helpful in understanding the role of highly species-specific pheromones and blends thereof, as well as an individual's response to the chemical cues in its environment.
Collapse
Affiliation(s)
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA.
| |
Collapse
|
35
|
Wensing KU, Koppik M, Fricke C. Precopulatory but not postcopulatory male reproductive traits diverge in response to mating system manipulation in Drosophila melanogaster. Ecol Evol 2017; 7:10361-10378. [PMID: 29238561 PMCID: PMC5723610 DOI: 10.1002/ece3.3542] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 01/01/2023] Open
Abstract
Competition between males creates potential for pre‐ and postcopulatory sexual selection and conflict. Theory predicts that males facing risk of sperm competition should evolve traits to secure their reproductive success. If those traits are costly to females, the evolution of such traits may also increase conflict between the sexes. Conversely, under the absence of sperm competition, one expectation is for selection on male competitive traits to relax thereby also relaxing sexual conflict. Experimental evolution studies are a powerful tool to test this expectation. Studies in multiple insect species have yielded mixed and partially conflicting results. In this study, we evaluated male competitive traits and male effects on female costs of mating in Drosophila melanogaster after replicate lines evolved for more than 50 generations either under enforced monogamy or sustained polygamy, thus manipulating the extent of intrasexual competition between males. We found that in a setting where males competed directly with a rival male for access to a female and fertilization of her ova polygamous males had superior reproductive success compared to monogamous males. When comparing reproductive success solely in double mating standard sperm competition assays, however, we found no difference in male sperm defense competitiveness between the different selection regimes. Instead, we found monogamous males to be inferior in precopulatory competition, which indicates that in our system, enforced monogamy relaxed selection on traits important in precopulatory rather than postcopulatory competition. We discuss our findings in the context of findings from previous experimental evolution studies in Drosophila ssp. and other invertebrate species.
Collapse
Affiliation(s)
- Kristina U. Wensing
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
- Muenster Graduate School of EvolutionUniversity of MuensterMuensterGermany
| | - Mareike Koppik
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
| | - Claudia Fricke
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
| |
Collapse
|
36
|
Fricke C, Chapman T. Variation in the post-mating fitness landscape in fruit flies. J Evol Biol 2017; 30:1250-1261. [PMID: 28391616 PMCID: PMC5518202 DOI: 10.1111/jeb.13090] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Revised: 03/24/2017] [Accepted: 04/03/2017] [Indexed: 12/16/2022]
Abstract
Sperm competition is pervasive and fundamental to determining a male's overall fitness. Sperm traits and seminal fluid proteins (Sfps) are key factors. However, studies of sperm competition may often exclude females that fail to remate during a defined period. Hence, the resulting data sets contain fewer data from the potentially fittest males that have most success in preventing female remating. It is also important to consider a male's reproductive success before entering sperm competition, which is a major contributor to fitness. The exclusion of these data can both hinder our understanding of the complete fitness landscapes of competing males and lessen our ability to assess the contribution of different determinants of reproductive success to male fitness. We addressed this here, using the Drosophila melanogaster model system, by (i) capturing a comprehensive range of intermating intervals that define the fitness of interacting wild-type males and (ii) analysing outcomes of sperm competition using selection analyses. We conducted additional tests using males lacking the sex peptide (SP) ejaculate component vs. genetically matched (SP+ ) controls. This allowed us to assess the comprehensive fitness effects of this important Sfp on sperm competition. The results showed a signature of positive, linear selection in wild-type and SP+ control males on the length of the intermating interval and on male sperm competition defence. However, the fitness surface for males lacking SP was distinct, with local fitness peaks depending on contrasting combinations of remating intervals and offspring numbers. The results suggest that there are alternative routes to success in sperm competition and provide an explanation for the maintenance of variation in sperm competition traits.
Collapse
Affiliation(s)
- C. Fricke
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichUK
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
| | - T. Chapman
- School of Biological SciencesUniversity of East AngliaNorwich Research ParkNorwichUK
| |
Collapse
|
37
|
Giardina TJ, Clark AG, Fiumera AC. Estimating mating rates in wild Drosophila melanogaster females by decay rates of male reproductive proteins in their reproductive tracts. Mol Ecol Resour 2017; 17:1202-1209. [PMID: 28213940 DOI: 10.1111/1755-0998.12661] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/01/2017] [Indexed: 11/29/2022]
Abstract
Female Drosophila melanogaster frequently mate with multiple males in nature as shown through parentage analysis. Although polyandry is well documented, we know little about the timing between mating events in wild Drosophila populations due to the challenge of following behaviours of individual females. In this study, we used the presence of a male reproductive protein that is transferred to the female during mating (Sex Peptide, SP) to determine whether she had recently mated. We sampled females throughout the day, conducted control matings to determine the decay rate of SP within the female reproductive tract and performed computer simulations to fit the observed proportion of mated females to a nonhomogenous Poisson process that defined the expected time between successive matings for a given female. In our control matings, 100% of mated females tested positive for SP 0.5 h after the start of mating (ASM), but only 24% tested positive 24 h ASM. Overall, 35% of wild-caught females tested positive for the presence of SP. Fitting our observed data to our simple nonhomogenous Poisson model provided the inference that females are mating, on average, approximately every 27 h (with 95% credibility interval 23-31 h). Thus, it appears that females are mating a bit less frequently that once per day in this natural population and that mating events tend to occur either early in the morning or late in the afternoon.
Collapse
Affiliation(s)
- Thomas J Giardina
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Andrew G Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| |
Collapse
|
38
|
Multiple Genes Cause Postmating Prezygotic Reproductive Isolation in the Drosophila virilis Group. G3-GENES GENOMES GENETICS 2016; 6:4067-4076. [PMID: 27729433 PMCID: PMC5144975 DOI: 10.1534/g3.116.033340] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Understanding the genetic basis of speciation is a central problem in evolutionary biology. Studies of reproductive isolation have provided several insights into the genetic causes of speciation, especially in taxa that lend themselves to detailed genetic scrutiny. Reproductive barriers have usually been divided into those that occur before zygote formation (prezygotic) and after (postzygotic), with the latter receiving a great deal of attention over several decades. Reproductive barriers that occur after mating but before zygote formation [postmating prezygotic (PMPZ)] are especially understudied at the genetic level. Here, I present a phenotypic and genetic analysis of a PMPZ reproductive barrier between two species of the Drosophila virilis group: D. americana and D. virilis This species pair shows strong PMPZ isolation, especially when D. americana males mate with D. virilis females: ∼99% of eggs laid after these heterospecific copulations are not fertilized. Previous work has shown that the paternal loci contributing to this incompatibility reside on two chromosomes, one of which (chromosome 5) likely carries multiple factors. The other (chromosome 2) is fixed for a paracentric inversion that encompasses nearly half the chromosome. Here, I present two results. First, I show that PMPZ in this species cross is largely due to defective sperm storage in heterospecific copulations. Second, using advanced intercross and backcross mapping approaches, I identify genomic regions that carry genes capable of rescuing heterospecific fertilization. I conclude that paternal incompatibility between D. americana males and D. virilis females is underlain by four or more genes on chromosomes 2 and 5.
Collapse
|
39
|
Plakke MS, Deutsch AB, Meslin C, Clark NL, Morehouse NI. Dynamic digestive physiology of a female reproductive organ in a polyandrous butterfly. ACTA ACUST UNITED AC 2016; 218:1548-55. [PMID: 25994634 DOI: 10.1242/jeb.118323] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Reproductive traits experience high levels of selection because of their direct ties to fitness, often resulting in rapid adaptive evolution. Much of the work in this area has focused on male reproductive traits. However, a more comprehensive understanding of female reproductive adaptations and their relationship to male characters is crucial to uncover the relative roles of sexual cooperation and conflict in driving co-evolutionary dynamics between the sexes. We focus on the physiology of a complex female reproductive adaptation in butterflies and moths: a stomach-like organ in the female reproductive tract called the bursa copulatrix that digests the male ejaculate (spermatophore). Little is known about how the bursa digests the spermatophore. We characterized bursa proteolytic capacity in relation to female state in the polyandrous butterfly Pieris rapae. We found that the virgin bursa exhibits extremely high levels of proteolytic activity. Furthermore, in virgin females, bursal proteolytic capacity increases with time since eclosion and ambient temperature, but is not sensitive to the pre-mating social environment. Post copulation, bursal proteolytic activity decreases rapidly before rebounding toward the end of a mating cycle, suggesting active female regulation of proteolysis and/or potential quenching of proteolysis by male ejaculate constituents. Using transcriptomic and proteomic approaches, we report identities for nine proteases actively transcribed by bursal tissue and/or expressed in the bursal lumen that may contribute to observed bursal proteolysis. We discuss how these dynamic physiological characteristics may function as female adaptations resulting from sexual conflict over female remating rate in this polyandrous butterfly.
Collapse
Affiliation(s)
- Melissa S Plakke
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Aaron B Deutsch
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Camille Meslin
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Nathan L Clark
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Nathan I Morehouse
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| |
Collapse
|
40
|
Travers LM, Garcia-Gonzalez F, Simmons LW. Genetic variation but weak genetic covariation between pre- and post-copulatory episodes of sexual selection in Drosophila melanogaster. J Evol Biol 2016; 29:1535-52. [PMID: 27159063 DOI: 10.1111/jeb.12890] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 04/20/2016] [Accepted: 04/29/2016] [Indexed: 12/16/2022]
Abstract
When females mate polyandrously, male reproductive success depends both on the male's ability to attain matings and on his ability to outcompete rival males in the fertilization of ova post-copulation. Increased investment in ejaculate components may trade off with investment in precopulatory traits due to resource allocation. Alternatively, pre- and post-copulatory traits could be positively related if individuals can afford to invest heavily in traits advantageous at both episodes of selection. There is empirical evidence for both positive and negative associations between pre- and post-copulatory episodes, but little is known about the genetic basis of these correlations. In this study, we measured morphological, chemical and behavioural precopulatory male traits and investigated their relationship with measures of male fitness (male mating success, remating inhibition and offensive sperm competitiveness) across 40 isofemale lines of Drosophila melanogaster. We found significant variation among isofemale lines, indicating a genetic basis for most of the traits investigated. However, we found weak evidence for genetic correlations between precopulatory traits and our indices of male fitness. Moreover, pre- and post-copulatory episodes of selection were uncorrelated, suggesting selection may act independently at the different episodes to maximize male reproductive success.
Collapse
Affiliation(s)
- L M Travers
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, WA, Australia
| | - F Garcia-Gonzalez
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, WA, Australia.,Doñana Biological Station, Spanish Research Council CSIC, Isla de la Cartuja, Seville, Spain
| | - L W Simmons
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, WA, Australia
| |
Collapse
|
41
|
Travers LM, Simmons LW, Garcia‐Gonzalez F. Additive genetic variance in polyandry enables its evolution, but polyandry is unlikely to evolve through sexy or good sperm processes. J Evol Biol 2016; 29:916-28. [DOI: 10.1111/jeb.12834] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 01/15/2016] [Indexed: 02/03/2023]
Affiliation(s)
- L. M. Travers
- Centre for Evolutionary Biology School of Animal Biology (M092) The University of Western Australia Crawley WA Australia
| | - L. W. Simmons
- Centre for Evolutionary Biology School of Animal Biology (M092) The University of Western Australia Crawley WA Australia
| | - F. Garcia‐Gonzalez
- Centre for Evolutionary Biology School of Animal Biology (M092) The University of Western Australia Crawley WA Australia
- Doñana Biological Station Spanish Research Council CSIC Sevilla Spain
| |
Collapse
|
42
|
|
43
|
Bonilla ML, Todd C, Erlandson M, Andres J. Combining RNA-seq and proteomic profiling to identify seminal fluid proteins in the migratory grasshopper Melanoplus sanguinipes (F). BMC Genomics 2015; 16:1096. [PMID: 26694822 PMCID: PMC4689059 DOI: 10.1186/s12864-015-2327-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 12/15/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Seminal fluid proteins control many aspects of fertilization and in turn, they play a key role in post-mating sexual selection and possibly reproductive isolation. Because effective proteome profiling relies on the availability of high-quality DNA reference databases, our knowledge of these proteins is still largely limited to model organisms with ample genetic resources. New advances in sequencing technology allow for the rapid characterization of transcriptomes at low cost. By combining high throughput RNA-seq and shotgun proteomic profiling, we have characterized the seminal fluid proteins secreted by the primary male accessory gland of the migratory grasshopper (Melanoplus sanguinipes), one of the main agricultural pests in central North America. RESULTS Using RNA sequencing, we characterized the transcripts of ~ 8,100 genes expressed in the long hyaline tubules (LHT) of the accessory glands. Proteomic profiling identified 353 proteins expressed in the long hyaline tubules (LHT). Of special interest are seminal fluid proteins (SFPs), such as EJAC-SP, ACE and prostaglandin synthetases, which are known to regulate female oviposition in insects. CONCLUSIONS Our study provides new insights into the proteomic components of male ejaculate in Orthopterans, and highlights several important patterns. First, the presence of proteins that lack predicted classical secretory tags in accessory gland proteomes is common in male accessory glands. Second, the products of a few highly expressed genes dominate the accessory gland secretions. Third, accessory gland transcriptomes are enriched for novel transcripts. Fourth, there is conservation of SFPs' functional classes across distantly related taxonomic groups with very different life histories, mating systems and sperm transferring mechanisms. The identified SFPs may serve as targets of future efforts to develop species- specific genetic control strategies.
Collapse
Affiliation(s)
- Martha L Bonilla
- Facultad de Ciencias Agropecuarias, Universidad Nacional de Colombia, A.237. Palmira, Valle del Cauca, Colombia.
- Department of Biology, University of Saskatchewan, 112 Science Pl., Saskatoon, SK, S7N-5E2, Canada.
| | - Christopher Todd
- Department of Biology, University of Saskatchewan, 112 Science Pl., Saskatoon, SK, S7N-5E2, Canada.
| | - Martin Erlandson
- Saskatoon Research Centre, Agriculture and Agri-Food Canada, 107 Science Pl., Saskatoon, SK, S7N-0X2, Canada.
| | - Jose Andres
- Department of Biology, University of Saskatchewan, 112 Science Pl., Saskatoon, SK, S7N-5E2, Canada.
| |
Collapse
|
44
|
Goenaga J, Yamane T, Rönn J, Arnqvist G. Within-species divergence in the seminal fluid proteome and its effect on male and female reproduction in a beetle. BMC Evol Biol 2015; 15:266. [PMID: 26627998 PMCID: PMC4667481 DOI: 10.1186/s12862-015-0547-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 11/20/2015] [Indexed: 11/30/2022] Open
Abstract
Background Male seminal fluid proteins (SFPs), transferred to females during mating, are important reproductive proteins that have multifarious effects on female reproductive physiology and that often show remarkably rapid and divergent evolution. Inferences regarding natural selection on SFPs are based primarily on interspecific comparative studies, and our understanding of natural within-species variation in SFPs and whether this relates to reproductive phenotypes is very limited. Here, we introduce an empirical strategy to study intraspecific variation in and selection upon the seminal fluid proteome. We then apply this in a study of 15 distinct populations of the seed beetle Callosobruchus maculatus. Results Phenotypic assays of these populations showed significant differences in reproductive phenotypes (male success in sperm competition and male ability to stimulate female fecundity). A quantitative proteomic study of replicated samples of male accessory glands revealed a large number of potential SFPs, of which ≥127 were found to be transferred to females at mating. Moreover, population divergence in relative SFP abundance across populations was large and remarkably multidimensional. Most importantly, variation in male SFP abundance across populations was associated with male sperm competition success and male ability to stimulate female egg production. Conclusions Our study provides the first direct evidence for postmating sexual selection on standing intraspecific variation in SFP abundance and the pattern of divergence across populations in the seminal fluid proteome match the pattern predicted by the postmating sexual selection paradigm for SFP evolution. Our findings provide novel support for the hypothesis that sexual selection on SFPs is an important engine of incipient speciation. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0547-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Julieta Goenaga
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden. .,Aarhus Institute of Advanced Studies, Aarhus University, Høegh-Guldbergs Gade 6B, 11 8000, Aarhus C, Denmark.
| | - Takashi Yamane
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| | - Johanna Rönn
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| | - Göran Arnqvist
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| |
Collapse
|
45
|
Rodríguez-García MJ, Machado V, Galián J. Identification and characterisation of putative seminal fluid proteins from male reproductive tissue EST libraries in tiger beetles. BMC Genomics 2015; 16:391. [PMID: 25981911 PMCID: PMC4434525 DOI: 10.1186/s12864-015-1619-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 05/05/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The study of proteins transferred through semen can provide important information for biological questions such as adaptive evolution, the origin of new species and species richness. The objective of this study was to identify seminal fluid proteins (SFPs) that may contribute to the study of the reproductive system of tiger beetles (cicindelids), a group of more than 2,500 species distributed worldwide that occupy a great diversity of habitats. RESULTS Two cDNA libraries were constructed from the male gonads of Calomera littoralis and Cephalota litorea. Expressed sequence tags (ESTs) were analysed by bioinformatics approaches and 14 unigenes were selected as candidate SFPs, which were submitted to Reverse Transcription Polymerase Chain Reaction (RT-PCR) to identify patterns of tissue-specific expression. We have identified four novel putative SFPs of cicindelids, of which similarity searches did not show homologues with known function. However, two of the protein classes (immune response and hormone) predicted by Protfun are similar to SFPs reported in other insects. Searches for homology in other cicindelids showed one lineage specific SFPs (rapidly evolving proteins), only present in the closely related species C. littoralis and Lophyra flexuosa and two conserved SFP present in other tiger beetles species tested. CONCLUSIONS This work represents the first characterisation of putative SFPs in Adephagan species of the order Coleoptera. The results will serve as a foundation for further studies aimed to understand gene (and protein) functions and their evolutionary implications in this group of ecologically relevant beetles.
Collapse
Affiliation(s)
- María Juliana Rodríguez-García
- Department of Zoology and Physical Anthropology, Faculty of Veterinary, University of Murcia, Campus Mare Nostrum, E-30100, Murcia, Spain.
| | - Vilmar Machado
- Department of Zoology and Physical Anthropology, Faculty of Veterinary, University of Murcia, Campus Mare Nostrum, E-30100, Murcia, Spain.
| | - José Galián
- Department of Zoology and Physical Anthropology, Faculty of Veterinary, University of Murcia, Campus Mare Nostrum, E-30100, Murcia, Spain.
| |
Collapse
|
46
|
Yamane T, Goenaga J, Rönn JL, Arnqvist G. Male seminal fluid substances affect sperm competition success and female reproductive behavior in a seed beetle. PLoS One 2015; 10:e0123770. [PMID: 25893888 PMCID: PMC4404252 DOI: 10.1371/journal.pone.0123770] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/27/2015] [Indexed: 01/14/2023] Open
Abstract
Male seminal fluid proteins are known to affect female reproductive behavior and physiology by reducing mating receptivity and by increasing egg production rates. Such substances are also though to increase the competitive fertilization success of males, but the empirical foundation for this tenet is restricted. Here, we examined the effects of injections of size-fractioned protein extracts from male reproductive organs on both male competitive fertilization success (i.e., P2 in double mating experiments) and female reproduction in the seed beetle Callosobruchus maculatus. We found that extracts of male seminal vesicles and ejaculatory ducts increased competitive fertilization success when males mated with females 1 day after the females’ initial mating, while extracts from accessory glands and testes increased competitive fertilization success when males mated with females 2 days after the females’ initial mating. Moreover, different size fractions of seminal fluid proteins had distinct and partly antagonistic effects on male competitive fertilization success. Collectively, our experiments show that several different seminal fluid proteins, deriving from different parts in the male reproductive tract and of different molecular weight, affect male competitive fertilization success in C. maculatus. Our results highlight the diverse effects of seminal fluid proteins and show that the function of such proteins can be contingent upon female mating status. We also document effects of different size fractions on female mating receptivity and egg laying rates, which can serve as a basis for future efforts to identify the molecular identity of seminal fluid proteins and their function in this model species.
Collapse
Affiliation(s)
| | - Julieta Goenaga
- Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
| | | | - Göran Arnqvist
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- * E-mail:
| |
Collapse
|
47
|
Hansen JM, Chavez DR, Stanfield GM. COMP-1 promotes competitive advantage of nematode sperm. eLife 2015; 4:e05423. [PMID: 25789512 PMCID: PMC4400581 DOI: 10.7554/elife.05423] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 03/16/2015] [Indexed: 12/24/2022] Open
Abstract
Competition among sperm to fertilize oocytes is a ubiquitous feature of sexual reproduction as well as a profoundly important aspect of sexual selection. However, little is known about the cellular mechanisms sperm use to gain competitive advantage or how these mechanisms are regulated genetically. In this study, we utilize a forward genetic screen in Caenorhabditis elegans to identify a gene, comp-1, whose function is specifically required in competitive contexts. We show that comp-1 functions in sperm to modulate their migration through and localization within the reproductive tract, thereby promoting their access to oocytes. Contrary to previously described models, comp-1 mutant sperm show no defects in size or velocity, thereby defining a novel pathway for preferential usage. Our results indicate not only that sperm functional traits can influence the outcome of sperm competition, but also that these traits can be modulated in a context-dependent manner depending on the presence of competing sperm.
Collapse
Affiliation(s)
- Jody M Hansen
- Department of Human Genetics, University of Utah, Salt Lake City, United States
| | - Daniela R Chavez
- Department of Human Genetics, University of Utah, Salt Lake City, United States
| | - Gillian M Stanfield
- Department of Human Genetics, University of Utah, Salt Lake City, United States
| |
Collapse
|
48
|
Vogel A, Jocque H, Sirot LK, Fiumera AC. Effects of atrazine exposure on male reproductive performance in Drosophila melanogaster. JOURNAL OF INSECT PHYSIOLOGY 2015; 72:14-21. [PMID: 25445663 PMCID: PMC4333012 DOI: 10.1016/j.jinsphys.2014.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/04/2014] [Accepted: 11/13/2014] [Indexed: 05/19/2023]
Abstract
Atrazine is a commonly utilized herbicide to control broadleaf weeds in the agricultural setting. It can, however, have negative effects on male reproductive performance in a variety of vertebrate species. Much less is known, however, about the effects of atrazine on invertebrates. In this study, we investigated the effects of several different concentrations of larval atrazine exposure on measures of reproductive performance in adult male Drosophila melanogaster. Atrazine exposure had significant effects on a male's mating ability and the number of eggs his partner laid when he was successful at mating. Exposed males also sired a smaller proportion of the offspring under competitive conditions when they were the first male to mate to a doubly mated female. Atrazine exposure had no measurable effect on a male's ability to prevent a mated female from mating to another male or on the proportion of offspring sired when the exposed males were the second male to mate. Exposure upregulated expression of one male reproductive gene, ovulin, but had no effect on expression of another, sex peptide. Exposed males produced and transferred more sex peptide protein to the female during mating but ovulin protein levels were not affected. In general, we observed non-monotonic responses such that the intermediate exposure levels showed the largest reduction in male reproductive performance. This study suggests that atrazine exposure affects male reproductive performance in insects and future studies should aim to understand the molecular mechanisms underlying the fitness effects of exposure.
Collapse
Affiliation(s)
- Andrea Vogel
- Department of Biological Sciences, Binghamton University, Binghamton, NY 13902, USA.
| | - Harper Jocque
- Department of Biology, The College of Wooster, Wooster, OH 44691, USA.
| | - Laura K Sirot
- Department of Biology, The College of Wooster, Wooster, OH 44691, USA.
| | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, NY 13902, USA.
| |
Collapse
|
49
|
Sirot LK. Ask not (only) what proteomics can do for behavior, but (also) what behavior can do for proteomes: a comment on Valcu and Kempenaers. Behav Ecol 2015. [DOI: 10.1093/beheco/aru168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
50
|
Exposure to endosulfan influences sperm competition in Drosophila melanogaster. Sci Rep 2014; 4:7433. [PMID: 25503806 PMCID: PMC4262826 DOI: 10.1038/srep07433] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 11/21/2014] [Indexed: 01/20/2023] Open
Abstract
Dwindling male fertility due to xenobiotics is of global concern. Accordingly, male reproductive toxicity assessment of xenobiotics through semen quality analysis in exposed males, and examining progeny production of their mates is critical. These assays, in part, are biased towards monogamy. Females soliciting multiple male partners (polyandry) is the norm in many species. Polyandry incites sperm competition and allows females to bias sperm use. However, consequences of xenobiotic exposure to the sperm in the light of sperm competition remain to be understood. Therefore, we exposed Drosophila melanogaster males to endosulfan, and evaluated their progeny production as well as the ability of their sperm to counter rival control sperm in the storage organs of females sequentially mated to control/exposed males. Endosulfan (2 μg/ml) had no significant effect on progeny production and on the expression of certain genes associated with reproduction. However, exposed males performed worse in sperm competition, both as 1(st) and 2(nd) male competitors. These findings indicate that simple non-competitive measures of reproductive ability may fail to demonstrate the harmful effects of low-level exposure to xenobiotics on reproduction and advocate consideration of sperm competition, as a parameter, in the reproductive toxicity assessment of xenobiotics to mimic situations prevailing in the nature.
Collapse
|