Male-female Communication Research Articles

Male–female chemical interactions in a facultatively parthenogenetic stick insect

AbstractFacultative parthenogenesis is a form of reproduction in which females can either lay unfertilised eggs that typically develop into female offspring only or mate and lay fertilised eggs that develop into male and female offspring. Intriguingly, facultative parthenogens often occur in mixed‐sex populations where reproduction is mostly sexual and all‐female populations where reproduction is asexual. How all‐female populations avoid invasion by males remains unknown. Here, we explored the use of pheromones in male–female communication in a facultatively parthenogenetic stick insect, the peppermint stick insect (Megacrania batesii), and compared chemical signals between females descended from sexually versus parthenogenetically reproducing populations. If parthenogenetic females release less attractive pheromones, this could help explain the persistence of all‐female populations. We found that M. batesii exhibits slight sexual dimorphism in antenna morphology, and behavioural assays provided little evidence that males could locate females solely by volatile pheromones. However, CHC profiles differed substantially between different types of females. Analysis of CHC components indicated a clear genetic difference between females descended from all‐female versus mixed‐sex populations, as well as a maternal effect of female parthenogenetic versus sexual development. Together, our results suggest that males might rely more on close‐range chemical cues to differentiate females, and chemical communication could play a role in the persistence of all‐female populations.

The emerging role of cysteine-rich peptides in pollen-pistil interactions.

Unlike early land plants, flowering plants have evolved a pollen tube that transports a pair of non-motile sperm cells to the female gametophyte. This process, known as siphonogamy, was first observed in gymnosperms and later became prevalent in angiosperms. However, the precise molecular mechanisms underlying the male-female interactions remain enigmatic. From the landing of the pollen grain on the stigma to gamete fusion, the male part needs to pass various tests: how does the stigma distinguish between compatible and incompatible pollen? what mechanisms guide the pollen tube towards the ovule? what factors trigger pollen tube rupture? how is polyspermy prevented? and how does the sperm cell ultimately reach the egg? Successful male-female communication is essential for surmounting these challenges, with cysteine-rich peptides (CRPs) playing a pivotal role in this dialogue. In this review, we summarize the characteristics of four distinct classes of CRPs, systematically review recent progress in the role of CRPs in four crucial stages of pollination and fertilization, consider potential applications of this knowledge in crop breeding, and conclude by suggesting avenues for future research.

From the archives: male-female communication, glue that keeps cells together, and a SUPERMAN for all flowering plants.

From the archives: male-female communication, glue that keeps cells together, and a SUPERMAN for all flowering plants.

A new species of Anisophya (Orthoptera: Tettigoniidae: Phaneropterinae) from Argentina, its ultrasound male-female communication, life history and ecology.

Anisophya arreguii sp. nov. is added as third species of the genus in Buenos Aires Province. A population living in humid meadows near La Plata, regularly observed during the last five years, was found to be different from A. punctinervis. It appears in two distinct annual generations. The male produces a continuous ultrasound calling song, to which the female responds with short signals after particular syllables. The verification of all Anisophya observations from Argentina on iNaturalist helped clarifying the distinctiveness of the new species. Some ecological aspects are briefly discussed, such as a vulnerable population in the city of La Plata.

Intergender communication as intralingual translation in Ubang, Southeastern Nigeria

The Ubang language in Obudu, Southeastern Nigeria, is asymmetric because communication among males and females or between them flows through two distinct linguistic codes. This phenomenon tends to challenge the nature of occurrence and use of language(s) in any given community. Is it a natural or a societal phenomenon? How does such intergender communication occur? To seek responses to these questions, this study sets out to interrogate the nature of male-female discourse in Ubang by observing 18 Ubang language speakers (nine males and nine females) in naturally occurring communication in their physical environment and analyzing their conversations using Peircean semiotics, the interpretative theory of translation and Susan Petrilli’s (2003) tripod of intralingual translation. It was discovered that male-female communication in Ubang is more a function of intralingual translation.

F-actin regulates the polarized secretion of pollen tube attractants in Arabidopsis synergid cells.

Pollen tube attraction is a key event of sexual reproduction in flowering plants. In the ovule, two synergid cells neighboring the egg cell control pollen tube arrival via the active secretion of attractant peptides such as AtLURE1 and XIUQIU from the filiform apparatus (FA) facing toward the micropyle. Distinctive cell polarity together with longitudinal F-actin and microtubules are hallmarks of the synergid cell in various species, though the functions of these cellular structures are unclear. In this study, we used genetic and pharmacological approaches to indicate the roles of cytoskeletal components in FA formation and pollen tube guidance in Arabidopsis thaliana. Genetic inhibition of microtubule formation reduced invaginations of the plasma membrane but did not abolish micropylar AtLURE1.2 accumulation. By contrast, the expression of a dominant-negative form of ACTIN8 induced disorganization of the FA and loss of polar AtLURE1.2 distribution toward the FA. Interestingly, after pollen tube reception, F-actin became unclear for a few hours in the persistent synergid cell, which may be involved in pausing and resuming pollen tube attraction during early polytubey block. Our data suggest that F-actin plays a central role in maintaining cell polarity and in mediating male-female communication in the synergid cell.

Male-female communication enhances release of extracellular vesicles leading to high fertility in Drosophila

The female reproductive tract (female-RT) must decipher the repertoire of molecular cues received from the male during copulation in order to activate and coordinate tract functionality necessary for high fertility. In Drosophila, this modulation is partially driven by spermathecal secretory cells (SSC). The SSC are a layer of cuboidal secretory glandular cells surrounding the spermatheca capsule where sperm is stored. It is unclear, however, how the SSC regulate the system’s activity. Here we show that mating activates the secretory machinery of the SSC. The SSC release a heterogeneous population of extracellular vesicles (EVs) which is involved in initiating and managing the increase in egg-laying, and possibly sperm storage. Moreover, sperm and male accessory gland proteins are essential for such mating-mediated SSC activity. Thus, mating regulates secretory/endocytic pathways required for trafficking of vesicles to SSC-female-RT target sites, which modulate and coordinate reproductive tract activity to achieve high fertility.

An interesting new record of the almost unknown brachypterous phaneropterine katydid Xenicola dohrni (Orthoptera: Tettigoniidae) from Argentina, and its high-ultrasound male-female communication.

The southernmost record of the neotropical genus Xenicola is documented. An apparently tiny population of X. dohrni, a species described long ago from southern Brazil without other published records, lives at the shore of the Río de la Plata, 1000 km further south. Perhaps it has been established there by means of floating vegetation. The acoustic communication of this species is also very interesting: The male produces with its minuscule tegmina brief signals with a carrier frequency range between 80 and 100 kHz. The female responds, and the male modifies its song when engaged in a duet. It modifies it further, when the female responds from very close. The paper includes a review of the records of Xenicola species on biodiversity observation platforms.

Early-exposure to new sex pheromone blends alters mate preference in female butterflies and in their offspring

While the diversity of sex pheromone communication systems across insects is well documented, the mechanisms that lead to such diversity are not well understood. Sex pheromones constitute a species-specific system of sexual communication that reinforces interspecific reproductive isolation. When odor blends evolve, the efficacy of male-female communication becomes compromised, unless preference for novel blends also evolves. We explore odor learning as a possible mechanism leading to changes in sex pheromone preferences in the butterfly Bicyclus anynana. Our experiments reveal mating patterns suggesting that mating bias for new blends can develop following a short learning experience, and that this maternal experience impacts the mating outcome of offspring without further exposure. We propose that odor learning can be a key factor in the evolution of sex pheromone blend recognition and in chemosensory speciation.

The Present is the Key to the Past: How Living Fossils in Namibia Share Insights on the Insects of Tertiary European Forests

Mantophasmatodean insects have been widely recorded in Cretaceous and Eocene amber. Although rare, Mantophasmatodeans are famous for a quite widespread occurrence in the Baltic area until the Eocene extinction, living in a Tertiary flora commonly associated with forested ecosystems. Close relatives are still alive in southern Africa, like those belonging to the Mantophasma genus, probably one of the most intriguing living fossils in the world. Some nymphs were collected in a Namibian plateau east of the Erongo Complex and carefully cultivated in a laboratory. Our main purpose was to investigate the entire life cycle of these Namibian living fossils to share novel insights in the palaeoclimate of Baltic Eocene. We unravelled the adult morphology and the postembryonic development of these intriguing insects, commonly called heelwalkers, and performed a comparison of the morphometric, ecological and ethological data between our specimens and the living species described so far in literature. Furthermore, we analysed the vibrational male–female communication of these primitive insects. The robust evidence provided here supports some controversial recent palynological assessments of the Eocene and show that the Baltic landscape was much more open than commonly thought.

Men are from Mars: The challenges of communicating as a male nursing student.

Male-female communication within nursing is often fraught with difficulties especially for male nurses as the try and assimilate themselves into a female dominated profession. It is clear that men and women possess different communication styles. Men tend to be forthright and to the point. Women on the other hand often view the world as a network of connections, as a negotiation for closeness and support and therefore centred on maintaining solidarity. The aim of this study was to explore the lived-experience of a group of male nursing students using Colaizzi's seven step data analysis within the phenomenological empirical framework. The central theme "Men are from Mars" identified two subthemes which included: calling a spade a spade in world of shovels and conscientious objector from the margins. Communication for the men in this study was difficult. The participants were sensitive of what and how they communicated could be misinterpreted which often left them feeling isolated. They were often perplexed how the female students spoke to and about each. The men on the other hand were open and honest in the way they communicated with each other; there was not misinterpretation the men knew exactly where they stood with each other.

Arabinogalactan proteins and their sugar chains: functions in plant reproduction, research methods, and biosynthesis.

The arabinogalactan protein (AGP) family is one of the most complex protein families and is ubiquitous in the plant kingdom. Moreover, it has been demonstrated to play various roles during plant reproduction. A typical AGP contains a hydroxyproline-rich core protein with high heterogeneity and varying numbers of polysaccharide side chains. However, the functions of the polysaccharide components (i.e. AG sugar chains) remain largely unknown due to the general difficulties associated with studying sugar chains in glycobiology. In recent years, methodological breakthroughs have resulted in substantial progress in AGP research. Here, we summarise the multiple roles of AGPs during plant gametophyte development and male-female communication, with a focus on recent advances. In addition, we discuss the analytical tools used in AGP research, and the biosynthesis and function of AG sugar chains. A comprehensive understanding of the AGP family will help clarify the mechanisms precisely controlling reproductive processes.

A Defense of the Cross-Cultural Approach to Male-Female (Mis)Communication

A Defense of the Cross-Cultural Approach to Male-Female (Mis)Communication

Maternal ENODLs Are Required for Pollen Tube Reception in Arabidopsis

During the angiosperm (flowering-plant) life cycle, double fertilization represents the hallmark between diploid and haploid generations [1]. The success of double fertilization largely depends on compatible communication between the male gametophyte (pollen tube) and the maternal tissues of the flower, culminating in precise pollen tube guidance to the female gametophyte (embryo sac) and its rupture torelease sperm cells. Several important factors involved in the pollen tube reception have been identified recently [2-6], but the underlying signaling pathways are far from being understood. Here, we report that a group of female-specific small proteins, early nodulin-like proteins (ENODLs, or ENs), are required for pollen tube reception. ENs are featured with a plastocyanin-like (PCNL) domain, an arabinogalactan (AG) glycomodule, and a predicted glycosylphosphatidylinositol (GPI) anchor motif. We show that ENs are asymmetrically distributed at the plasma membrane of the synergid cells and accumulate at the filiform apparatus, where arriving pollen tubes communicate with the embryo sac. EN14 strongly and specifically interacts with the extracellular domain of the receptor-like kinase FERONIA, localized at the synergid cell surface and known to critically control pollen tube reception [6]. Wild-type pollen tubes failed to arrest growth and to rupture after entering the ovules of quintuple loss-of-function EN mutants, indicating a central role of ENs in male-female communication and pollen tube reception. Moreover, overexpression of EN15 by the endogenous promoter caused disturbed pollen tube guidance and reduced fertility. These data suggest that female-derived GPI-anchored ENODLs play an essential role in male-female communication and fertilization.

Information content and acoustic structure of male African elephant social rumbles.

Until recently, the prevailing theory about male African elephants (Loxodonta africana) was that, once adult and sexually mature, males are solitary and targeted only at finding estrous females. While this is true during the state of ‘musth’ (a condition characterized by aggressive behavior and elevated androgen levels), ‘non-musth’ males exhibit a social system seemingly based on companionship, dominance and established hierarchies. Research on elephant vocal communication has so far focused on females, and very little is known about the acoustic structure and the information content of male vocalizations. Using the source and filter theory approach, we analyzed social rumbles of 10 male African elephants. Our results reveal that male rumbles encode information about individuality and maturity (age and size), with formant frequencies and absolute fundamental frequency values having the most informative power. This first comprehensive study on male elephant vocalizations gives important indications on their potential functional relevance for male-male and male-female communication. Our results suggest that, similar to the highly social females, future research on male elephant vocal behavior will reveal a complex communication system in which social knowledge, companionship, hierarchy, reproductive competition and the need to communicate over long distances play key roles.

A garlic substance disrupts odorant-binding protein recognition of insect pheromones released from adults of the angoumois grain moth, Sitotroga cerealella (Lepidoptera: Gelechiidae).

The angoumois grain moth, Sitotroga cerealella, is one of the most serious stored-grain pests worldwide. Control of this moth may be achieved by interfering with olfactory pathways to disrupt male-female communication with sex pheromones, using plant volatiles like garlic or its active substances. Here, three odorant-binding protein (OBP) genes [namely Si. cerealella general OBP 1 (ScerGOBP1), ScerGOBP2 and Si. cerealella pheromone-binding protein (ScerPBP)] were cloned from Si. cerealella antennae, and quantitative real-time PCR showed that these genes were predominantly expressed in adult antennae. ScerPBP expression was male-biased, but ScerGOBP1 and ScerGOBP2 were similar between sexes. The results of competitive binding assays indicated that a garlic substance, diallyl trisulphide (DATS), had similar or even higher binding affinity to ScerPBP than Si. cerealella sex pheromone, 7Z, 11E-hexadecadien-1-ol acetate (HDA). In olfactometer bioassays, DATS significantly reduced the response of adults to HDA when they were exposed to air filled with HDA and DATS. Surprisingly, ScerGOBP2, which is postulated to be involved in the detection of general odours, displayed higher affinity with HDA than did ScerPBP, indicating that ScerGOBP2 may also have a role in pheromone perception. These data suggest that DATS may interfere with recognition of female-produced sex pheromone, disrupting female and male mating behaviour and resulting in a new idea for controlling stored grain pests.

Tip-localized receptors control pollen tube growth and LURE sensing in Arabidopsis.

Directional control of tip-growing cells is essential for proper tissue organization and cell-to-cell communication in animals and plants. In the sexual reproduction of flowering plants, the tip growth of the male gametophyte, the pollen tube, is precisely guided by female cues to achieve fertilization. Several female-secreted peptides have recently been identified as species-specific attractants that directly control the direction of pollen tube growth. However, the method by which pollen tubes precisely and promptly respond to the guidance signal from their own species is unknown. Here we show that tip-localized pollen-specific receptor-like kinase 6 (PRK6) with an extracellular leucine-rich repeat domain is an essential receptor for sensing of the LURE1 attractant peptide in Arabidopsis thaliana under semi-in-vivo conditions, and is important for ovule targeting in the pistil. PRK6 interacted with pollen-expressed ROPGEFs (Rho of plant guanine nucleotide-exchange factors), which are important for pollen tube growth through activation of the signalling switch Rho GTPase ROP1 (refs 7, 8). PRK6 conferred responsiveness to AtLURE1 in pollen tubes of the related species Capsella rubella. Furthermore, our genetic and physiological data suggest that PRK6 signalling through ROPGEFs and sensing of AtLURE1 are achieved in cooperation with the other PRK family receptors, PRK1, PRK3 and PRK8. Notably, the tip-focused PRK6 accumulated asymmetrically towards an external AtLURE1 source before reorientation of pollen tube tip growth. These results demonstrate that PRK6 acts as a key membrane receptor for external AtLURE1 attractants, and recruits the core tip-growth machinery, including ROP signalling proteins. This work provides insights into the orchestration of efficient pollen tube growth and species-specific pollen tube attraction by multiple receptors during male-female communication.

Investigation and analysis of contraceptive measures towards different reproductive-aged women in Yangzhou

Objective: This study aims to retrospectively investigate the contraceptive methods of different reproductive-aged women in two different regions of Yangzhou, China, to understand the changes of the contraceptive methods, and to analyze the targeted improvements of future informed choices of contraception and birth control, and reduce the occurrence of the unintended pregnancies. Materials and Methods: This study included 13,407 and 20,876 married reproductive-aged women (MCW) that were chosen from a city downtown and a county-level city, respectively, for the group-organized random sampling questionnaire survey. Results: There was a significant urban-rural difference in the choice of contraceptive methods in different MCW. The female choices of contraception were single; the accessibility of contraceptive supplies, and personalized services could improve the implementation rate of long-term contraceptive measures. The cooperation of male contraceptive responsibility was related to the education levels and enhanced male-female communication. Conclusions: It was very important for urban and rural women with different ages to choose different contraceptive measures, suggesting that these choices require the development of different educational models towards women of different ages and regions. The accessibility to various aspects of counseling and contraceptive measures should be strengthened, meanwhile male participation should also be promoted to prevent unwanted pregnancies and to reduce the health hazards related to sexual activities.

Zebra finch mates use their forebrain song system in unlearned call communication.

Unlearned calls are produced by all birds whereas learned songs are only found in three avian taxa, most notably in songbirds. The neural basis for song learning and production is formed by interconnected song nuclei: the song control system. In addition to song, zebra finches produce large numbers of soft, unlearned calls, among which “stack” calls are uttered frequently. To determine unequivocally the calls produced by each member of a group, we mounted miniature wireless microphones on each zebra finch. We find that group living paired males and females communicate using bilateral stack calling. To investigate the role of the song control system in call-based male female communication, we recorded the electrical activity in a premotor nucleus of the song control system in freely behaving male birds. The unique combination of acoustic monitoring together with wireless brain recording of individual zebra finches in groups shows that the neuronal activity of the song system correlates with the production of unlearned stack calls. The results suggest that the song system evolved from a brain circuit controlling simple unlearned calls to a system capable of producing acoustically rich, learned vocalizations.

Male-female communication triggers calcium signatures during fertilization in Arabidopsis.

Cell–cell communication and interaction is critical during fertilization and triggers free cytosolic calcium ([Ca2+]cyto) as a key signal for egg activation and a polyspermy block in animal oocytes. Fertilization in flowering plants is more complex, involving interaction of a pollen tube with egg adjoining synergid cells, culminating in release of two sperm cells and their fusion with the egg and central cell, respectively. Here, we report the occurrence and role of [Ca2+]cyto signals during the entire double fertilization process in Arabidopsis. [Ca2+]cyto oscillations are initiated in synergid cells after physical contact with the pollen tube apex. In egg and central cells, a short [Ca2+]cyto transient is associated with pollen tube burst and sperm cell arrival. A second extended [Ca2+]cyto transient solely in the egg cell is correlated with successful fertilization. Thus, each female cell type involved in double fertilization displays a characteristic [Ca2+]cyto signature differing by timing and behaviour from [Ca2+]cyto waves reported in mammals.