scholarly journals Apical Sperm Hook Morphology Is Linked to Sperm Swimming Performance and Sperm Aggregation in Peromyscus Mice

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2279
Author(s):  
Kristin A. Hook ◽  
Lauren M. Wilke ◽  
Heidi S. Fisher
Keyword(s):  
Sperm Competition ◽  
Reproductive Tract ◽  
Swimming Performance ◽  
Structural Diversity ◽  
Female Reproductive Tract ◽  
Eutherian Mammal ◽  
Male Sperm ◽  
Specific Variation ◽  
Sperm Swimming Speed

Mammals exhibit a tremendous amount of variation in sperm morphology and despite the acknowledgement of sperm structural diversity across taxa, its functional significance remains poorly understood. Of particular interest is the sperm of rodents. While most Eutherian mammal spermatozoa are relatively simple cells with round or paddle-shaped heads, rodent sperm are often more complex and, in many species, display a striking apical hook. The function of the sperm hook remains largely unknown, but it has been hypothesized to have evolved as an adaptation to inter-male sperm competition and thus has been implicated in increased swimming efficiency or in the formation of collective sperm movements. Here we empirically test these hypotheses within a single lineage of Peromyscus rodents, in which closely related species naturally vary in their mating systems, sperm head shapes, and propensity to form sperm aggregates of varying sizes. We performed sperm morphological analyses as well as in vitro analyses of sperm aggregation and motility to examine whether the sperm hook (i) morphologically varies across these species and (ii) associates with sperm competition, aggregation, or motility. We demonstrate inter-specific variation in the sperm hook and then show that hook width negatively associates with sperm aggregation and sperm swimming speed, signifying that larger hooks may be a hindrance to sperm movement within this group of mice. Finally, we confirmed that the sperm hook hinders motility within a subset of Peromyscus leucopus mice that spontaneously produced sperm with no or highly abnormal hooks. Taken together, our findings suggest that any adaptive value of the sperm hook is likely associated with a function other than inter-male sperm competition, such as interaction with ova or cumulous cells during fertilization, or migration through the complex female reproductive tract.

scholarly journals Collective sperm movements in Peromyscus mice are shaped by phylogenetic history and post-copulatory sexual selection

2020 ◽  
Author(s):  
Kristin A. Hook ◽  
W. David Weber ◽  
Heidi S. Fisher
Keyword(s):  
Sexual Selection ◽  
Sperm Competition ◽  
Reproductive Tract ◽  
Swimming Performance ◽  
Aggregate Size ◽  
Female Reproductive Tract ◽  
Testis Size ◽  
Limited Evidence ◽  
Closely Related Species ◽  
Sperm Migration

AbstractIn some species, sperm form motile, coordinated groups as they migrate through the female reproductive tract. Collective sperm migration is posited to have evolved to improve sperm swimming performance, and thus may be beneficial in a competitive context, but limited evidence supports this theory. Here we investigate sperm aggregation across closely-related species of Peromyscus mice that naturally vary by mating system. We find that phylogenetic history predicts the likelihood that sperm will aggregate but that variation in aggregate size negatively associates with relative testis size, suggesting that sperm competition has a stabilizing effect on this trait. Moreover, we show that sperm aggregation is not kinematically beneficial for all species, and we hypothesize that swimming performance is dependent on the orientation and composition of sperm groups. To test this, we compared sperm from the two sister-species that aggregate most frequently and find that sperm of the species that evolved under intense sperm competition forms aggregates with efficient geometry more frequently than sperm from its monogamous congener. Together, our results are consistent with the hypothesis that sperm aggregation evolved to improve motility in a competitive context; however, when monogamy evolved secondarily, relaxed sexual selection allowed for less efficient strategies to persist.

scholarly journals Organoids of the female reproductive tract

2021 ◽  
Vol 99 (4) ◽  
pp. 531-553 ◽  
Author(s):  
Cindrilla Chumduri ◽  
Margherita Y. Turco
Keyword(s):  
Reproductive Tract ◽  
Personalised Medicine ◽  
Three Dimensional ◽  
In Vitro Models ◽  
Experimental Models ◽  
Female Reproductive Tract ◽  
Cellular Heterogeneity ◽  
Dynamic Regulation ◽  
Pregnancy And Childbirth

AbstractHealthy functioning of the female reproductive tract (FRT) depends on balanced and dynamic regulation by hormones during the menstrual cycle, pregnancy and childbirth. The mucosal epithelial lining of different regions of the FRT—ovaries, fallopian tubes, uterus, cervix and vagina—facilitates the selective transport of gametes and successful transfer of the zygote to the uterus where it implants and pregnancy takes place. It also prevents pathogen entry. Recent developments in three-dimensional (3D) organoid systems from the FRT now provide crucial experimental models that recapitulate the cellular heterogeneity and physiological, anatomical and functional properties of the organ in vitro. In this review, we summarise the state of the art on organoids generated from different regions of the FRT. We discuss the potential applications of these powerful in vitro models to study normal physiology, fertility, infections, diseases, drug discovery and personalised medicine.

Effects of condition and sperm competition risk on sperm allocation and storage in neriid flies

2019 ◽  
Author(s):  
Zachariah Wylde ◽  
Angela Crean ◽  
Russell Bonduriansky
Keyword(s):  
Sperm Competition ◽  
Perceived Risk ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
The Body ◽  
Condition Dependence ◽  
Ejaculate Size ◽  
Sperm Competition Risk ◽  
High Condition ◽  
Allocation Strategies

Abstract Ejaculate traits can be sexually selected and often exhibit heightened condition-dependence. However, the influence of sperm competition risk in tandem with condition-dependent ejaculate allocation strategies is relatively unstudied. Because ejaculates are costly to produce, high-condition males may be expected to invest more in ejaculates when sperm competition risk is greater. We examined the condition-dependence of ejaculate size by manipulating nutrient concentration in the juvenile (larval) diet of the neriid fly Telostylinus angusticollis. Using a fully factorial design we also examined the effects of perceived sperm competition risk (manipulated by allowing males to mate first or second) on the quantity of ejaculate transferred and stored in the three spermathecae of the female reproductive tract. To differentiate male ejaculates, we fed males nontoxic rhodamine fluorophores (which bind to proteins in the body) prior to mating, labeling their sperm red or green. We found that high-condition males initiated mating more quickly and, when mating second, transferred more ejaculate to both of the female’s posterior spermathecae. This suggests that males allocate ejaculates strategically, with high-condition males elevating their ejaculate investment only when facing sperm competition. More broadly, our findings suggest that ejaculate allocation strategies can incorporate variation in both condition and perceived risk of sperm competition.

Post-Copulatory Sexual Selection

2021 ◽  
Author(s):  
Patricia L.R. Brennan ◽  
Dara N. Orbach
Keyword(s):  
Sexual Selection ◽  
Sperm Competition ◽  
Female Choice ◽  
Reproductive Tract ◽  
Seminal Fluid ◽  
Fertilization Success ◽  
Female Reproductive Tract ◽  
Cryptic Female Choice ◽  
Trade Offs ◽  
Morphological Criteria

The field of post-copulatory sexual selection investigates how female and male adaptations have evolved to influence the fertilization of eggs while optimizing fitness during and after copulation, when females mate with multiple males. When females are polyandrous (one female mates with multiple males), they may optimize their mating rate and control the outcome of mating interactions to acquire direct and indirect benefits. Polyandry may also favor the evolution of male traits that offer an advantage in post-copulatory male-male sperm competition. Sperm competition occurs when the sperm, seminal fluid, and/or genitalia of one male directly impacts the outcome of fertilization success of a rival male. When a female mates with multiple males, she may use information from a number of traits to choose who will sire her offspring. This cryptic female choice (CFC) to bias paternity can be based on behavioral, physiological, and morphological criteria (e.g., copulatory courtship, volume and/or composition of seminal fluid, shape of grasping appendages). Because male fitness interests are rarely perfectly aligned with female fitness interests, sexual conflict over mating and fertilization commonly occur during copulatory and post-copulatory interactions. Post-copulatory interactions inherently involve close associations between female and male reproductive characteristics, which in many species potentially include sperm storage and sperm movement inside the female reproductive tract, and highlight the intricate coevolution between the sexes. This coevolution is also common in genital morphology. The great diversity of genitalia among species is attributed to sexual selection. The evolution of genital attributes that allow females to maintain reproductive autonomy over paternity via cryptic female choice or that prevent male manipulation and sexual control via sexually antagonistic coevolution have been well documented. Additionally, cases where genitalia evolve through intrasexual competition are well known. Another important area of study in post-copulatory sexual selection is the examination of trade-offs between investments in pre-copulatory and post-copulatory traits, since organisms have limited energetic resources to allocate to reproduction, and securing both mating and fertilization is essential for reproductive success.

scholarly journals Spermatozoa Obtained From Alpaca vas deferens. Effects of Seminal Plasma Added at Post-thawing

2021 ◽  
Vol 8 ◽  
Author(s):  
Eduardo G. Aisen ◽  
Wilfredo Huanca López ◽  
Manuel G. Pérez Durand ◽  
Edita Torres Mamani ◽  
Juan C. Villanueva Mori ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Artificial Insemination ◽  
Reproductive Tract ◽  
Vas Deferens ◽  
Female Reproductive Tract ◽  
Low Fertility ◽  
Sperm Cells ◽  
South American Camelids ◽  
Thawing Process

The viscous seminal plasma (SP) is currently a major impediment to the handling of ejaculate and the development of some biotechnologies in South American camelids. The vas deferens-collected spermatozoa of alpacas is a useful technique to avoid this problem. On the other hand, SP contains a large protein component that has been implicated in the function of spermatozoa within the female reproductive tract. In this sense, the low fertility achieved using transcervical insemination with frozen-thawed spermatozoa in alpacas could be improved by adding SP. This study aimed to evaluate the effect of the whole SP on some in vitro parameters of alpaca spermatozoa after the freezing-thawing-process and the fertility after artificial insemination. It would contribute to a better understanding of the interaction between thawed sperm cells and SP. Spermatozoa were obtained by surgically diverted vas deferens. The samples were diluted with a Tris-based extender, packaged in straws, and frozen. At thawing, each straw was divided into two post-thawing conditions: with the addition of 10% of PBS (control) or with 10% SP (treatment). The sperm cells were evaluated using dynamic parameters, sperm cell morphology, and morphometry. Fertility was assessed by an artificial insemination trial. All in vitro parameters were analyzed by ANOVA. A heterogeneity test was scheduled for the fertility trial. After the freezing-thawing process, motility and plasma membrane functionality was improved when SP was added. No differences were found for post-thaw viability between the control and treatment samples. The percentage of normal cells was higher with SP at post-thawing, and a decrease of the presence of bent tailed spermatozoa with a droplet in the SP group was observed. The length of the head spermatozoa was 3.4% higher in the samples with PBS compared to those in which SP was added. Females pregnant at day 25 post-insemination were 0/12 (with SP inside the straw) and 1/10 (without SP inside the straw). In conclusion, the presence of 10% SP at post-thawing improves sperm cells' motility, functionality, and morphology, indicating that it would be beneficial to improve the frozen-thawed alpaca's physiology spermatozoa. More fertility trials must be developed to increase this knowledge.

Development of parthenogenetic and fertilized mouse embryos in the uterus and in extra-uterine sites

Development ◽  
1975 ◽  
Vol 34 (2) ◽  
pp. 387-405
Author(s):  
S. A. Iles ◽  
M. W. McBurney ◽  
S. R. Bramwell ◽  
Z. A. Deussen ◽  
C. F. Graham
Keyword(s):  
Reproductive Tract ◽  
Neural Tissue ◽  
Cell Types ◽  
Mouse Embryos ◽  
Female Reproductive Tract ◽  
Embryonic Cells ◽  
Haploid Embryos ◽  
Keratinized Epithelium ◽  
Mouse Eggs

Mouse eggs were activated with hyaluronidase in vitro and subsequently transferred to the oviduct. In the female reproductive tract they formed morulae and blastocysts which died soon after implantation. Haploid blastocysts were transferred beneath the kidney capsule and here some formed disorganized egg-cylinder structures in a week. Morulae and blastocysts from haploid and diploid parthenogenones were also transferred beneath the testis capsule. Two to four months later the growths which had formed were sectioned. They contained neural tissue, pigment, keratinized epithelium, glandular epithelium, ciliated epithelium, cartilage, bone, muscle, adipose tissue, and haemopoietic tissue. The range of cell types was similar to that produced by fertilized control blastocysts except that the parthenogenones did not form identifiable yolk-sac carcinoma or embryonal carcinomacells. The growths from haploid and diploid parthenogenones in the testis were stained with Feulgen and their DNA content measured. Growths from diploid embryos contained the normal diploid amount of DNA while growths from haploid embryos contained less than this amount. Cell cultures were prepared from the growths. The cells which were investigated contained no Y chromosome, suggesting that they were derived from the embryonic cells rather than the cells of the male host. These cells contained a near diploid chromosome number, although some of them were originally derived from haploid embryos.

scholarly journals CatSperζ regulates the structural continuity of sperm Ca2+ signaling domains and is required for normal fertility

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Jean-Ju Chung ◽  
Kiyoshi Miki ◽  
Doory Kim ◽  
Sang-Hee Shim ◽  
Huanan F Shi ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Targeted Disruption ◽  
Vitro Fertilization ◽  
Male Subfertility ◽  
Epididymal Spermatozoa ◽  
Mammalian Female ◽  
Signaling Domains

We report that the Gm7068 (CatSpere) and Tex40 (CatSperz) genes encode novel subunits of a 9-subunit CatSper ion channel complex. Targeted disruption of CatSperz reduces CatSper current and sperm rheotactic efficiency in mice, resulting in severe male subfertility. Normally distributed in linear quadrilateral nanodomains along the flagellum, the complex lacking CatSperζ is disrupted at ~0.8 μm intervals along the flagellum. This disruption renders the proximal flagellum inflexible and alters the 3D flagellar envelope, thus preventing sperm from reorienting against fluid flow in vitro and efficiently migrating in vivo. Ejaculated CatSperz-null sperm cells retrieved from the mated female uterus partially rescue in vitro fertilization (IVF) that failed with epididymal spermatozoa alone. Human CatSperε is quadrilaterally arranged along the flagella, similar to the CatSper complex in mouse sperm. We speculate that the newly identified CatSperζ subunit is a late evolutionary adaptation to maximize fertilization inside the mammalian female reproductive tract.

scholarly journals Do spermathecal morphology and inter-mating interval influence paternity in the polyandrous beetle Tribolium castaneum?

Behaviour ◽  
2006 ◽  
Vol 143 (5) ◽  
pp. 643-658 ◽  
Author(s):  
Ludovic Arnaud ◽  
Giorgina Bernasconi ◽  
Yves Brostaux ◽  
Eric P. Meyer
Keyword(s):  
Sperm Competition ◽  
Tribolium Castaneum ◽  
Reproductive Tract ◽  
Sperm Storage ◽  
Female Reproductive Tract ◽  
Phenotypic Marker ◽  
Male And Female ◽  
The Difference ◽  
Different Strains

AbstractIn polyandrous insects, postcopulatory sexual selection is a pervasive evolutionary force favouring male and female traits that allow control of offspring paternity. Males may influence paternity through adaptations for sperm competition, and females through adaptations facilitating cryptic female choice. Yet, the mechanisms are often complex, involving behaviour, physiology or morphology, and they are difficult to identify. In red flour beetles (Tribolium castaneum), paternity varies widely, and evidence suggests that both male and female traits influence the outcome of sperm competition. To test the role of spermathecal morphology and of sperm storage processes on the outcome of sperm competition, we mated each of 26 virgin females with two males, one of which carrying a phenotypic marker to assign offspring paternity. We manipulated the interval between mating with the first and the second male, to create different conditions of sperm storage (overlapping and non-overlapping) in the female reproductive tract. To investigate the role of sperm storage more closely, we examined the relationship between paternity and spermathecal morphology in a subset of 14 experimental females. In addition, we also characterized variation in spermathecal morphology in three different strains, wildtype, Chicago black and Reindeer. No significant influence of the intermating interval was found on the paternity of the focal male, although the direction of the difference was in the expected direction of higher last male paternity for longer intervals. Moreover, paternity was not significantly associated with spermathecal morphology, although spermathecal volume, complexity, and tubule width varied significantly and substantially among individuals in all investigated strains.

301 THE EFFECT OF EQUINE FOLICULLAR FLUID ON IN VITRO INDUCTION OF THE ACROSOME REACTION IN FROZEN - THAWED STALLION SPERMATOZOA

2010 ◽  
Vol 22 (1) ◽  
pp. 307
Author(s):  
D. S. Silva ◽  
P. Rodriguez ◽  
N. S. Arruda ◽  
R. Rodrigues ◽  
J. L. Rodrigues
Keyword(s):  
Contact Area ◽  
Follicular Fluid ◽  
Acrosome Reaction ◽  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Heparin Group ◽  
Fluorescent Stain ◽  
In Vitro Induction

The capacitation process occurs in vivo upon exposure of the spermatozoa through the female reproductive tract, but can be induced in vitro in the presence of several compounds. This study was conducted to assess the effect of heparin or equine follicular fluid on hyperactivated motility and in vitro induction acrosome reaction swim-up method with frozen-thawed stallion semen. Two hundred microliters of frozen-thawed equine semen was placed in a tube (45°C) to increase contact area and incubated at 37°C for 1 h. After incubation 800 μL of the supernatant was collected by centrifugation (500 × g, 10 min) to collect spermatozoa. The resulting pellet was resuspended in capacitation medium Fert-TALP supplemented with 5.0 μg mL-1 heparin or 100% follicular fluid and incubated for different times (1, 2, 3, 4, and 5 h) at 37°C. After incubation the hyperactivated motility and acrosome-reacted spermatozoa were evaluated. Hoechst stain was used to differentiate live and dead spermatozoa, and chlortetracycline (CTC) fluorescent stain was used to assess the capacitation response of sperm; data were analyzed by ANOVA. The effect of equine follicular fluid resulted in improved percentage of spermatozoa with acrosome reaction at all times of incubation (60, 63, 57, 52, and 58%) but immediately after 3 h of incubation, the hyperactivated motility decreased in heparin group and follicular fluid (42 and 30%, respectively).

scholarly journals ESR1 Mutations Associated With Estrogen Insensitivity Syndrome Change Conformation of Ligand-Receptor Complex and Altered Transcriptome Profile

Endocrinology ◽  
2020 ◽  
Vol 161 (6) ◽  
Author(s):  
Yin Li ◽  
Katherine J Hamilton ◽  
Lalith Perera ◽  
Tianyuan Wang ◽  
Artiom Gruzdev ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Reproductive Tract ◽  
Biological Effects ◽  
Estrogen Receptor Α ◽  
Female Reproductive Tract ◽  
Receptor Complexes ◽  
Esr1 Gene ◽  
Esr1 Mutations

Abstract Estrogen insensitivity syndrome (EIS) arises from rare mutations in estrogen receptor-α (ERα, encoded by ESR1 gene) resulting in the inability of estrogen to exert its biological effects. Due to its rarity, mutations in ESR1 gene and the underlying molecular mechanisms of EIS have not been thoroughly studied. Here, we investigate known ESR1 mutants, Q375H and R394H, associated with EIS patients using in vitro and in vivo systems. Comparison of the transcriptome and deoxyribonucleic acid methylome from stable cell lines of both Q375H and R394H clinical mutants shows a differential profile compared with wild-type ERα, resulting in loss of estrogen responsiveness. Molecular dynamic simulation shows that both ESR1 mutations change the ERα conformation of the ligand-receptor complexes. Furthermore, we generated a mouse model Esr1-Q harboring the human mutation using CRISPR/Cas9 genome editing. Female and male Esr1-Q mice are infertile and have similar phenotypes to αERKO mice. Overall phenotypes of the Esr1-Q mice correspond to those observed in the patient with Q375H. Finally, we explore the effects of a synthetic progestogen and a gonadotropin-releasing hormone inhibitor in the Esr1-Q mice for potentially reversing the impaired female reproductive tract function. These findings provide an important basis for understanding the molecular mechanistic consequences associated with EIS.

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