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Journal of Insect Science (Online) Nov 2020Oviposition-related genes have remained a consistent focus of insect molecular biology. Previous research has gradually clarified our mechanistic understanding of... (Review)
Review
Oviposition-related genes have remained a consistent focus of insect molecular biology. Previous research has gradually clarified our mechanistic understanding of oviposition-related genes, including those related to oviposition-gland-related genes, oogenesis-related genes, oviposition-site-selection-related genes, and genes related to ovulation and hatching. Moreover, some of this research has revealed how the expression of single oviposition-related genes affects the expression of related genes, and more importantly, how individual node genes function to link the expression of upstream and downstream genes. However, the research to date is not sufficient to completely explain the overall interactions among the genes of the insect oviposition system. Through a literature review of a large number of studies, this review provides references for future research on oviposition-related genes in insects and the use of RNAi or CRISPR/Cas9 technology to verify the functions of oviposition-related genes and to prevent and control harmful insects.
Topics: Animals; CRISPR-Cas Systems; Egg Proteins; Female; Gene Expression; Genes, Insect; Insect Control; Insecta; Oogenesis; Oviposition; RNA Interference; Receptors, Cell Surface; Vitellogenins
PubMed: 33367730
DOI: 10.1093/jisesa/ieaa137 -
Current Biology : CB Aug 2020Maternal decisions, such as where to build a nest or where to lay your eggs, are critical for the offspring's fitness and survival in any species. A new study in...
Maternal decisions, such as where to build a nest or where to lay your eggs, are critical for the offspring's fitness and survival in any species. A new study in Drosophila now reveals that distinct classes of mechanosensory receptors and neurons fine tune the physical assessment of an oviposition site and determine where the female fly lays her eggs.
Topics: Animals; Drosophila; Drosophila melanogaster; Eggs; Female; Neurons; Oviposition
PubMed: 32810453
DOI: 10.1016/j.cub.2020.06.082 -
Nature Communications May 2023Colonization of a novel ecological niche can require, or be driven by, evolution of an animal's behaviors promoting their reproductive success. We investigated the...
Colonization of a novel ecological niche can require, or be driven by, evolution of an animal's behaviors promoting their reproductive success. We investigated the evolution and sensory basis of oviposition in Drosophila sechellia, a close relative of Drosophila melanogaster that exhibits extreme specialism for Morinda citrifolia noni fruit. D. sechellia produces fewer eggs than other drosophilids and lays these almost exclusively on noni substrates. We show that visual, textural and social cues do not explain this species-specific preference. By contrast, we find that loss of olfactory input in D. sechellia, but not D. melanogaster, essentially abolishes egg-laying, suggesting that olfaction gates gustatory-driven noni preference. Noni odors are detected by redundant olfactory pathways, but we discover a role for hexanoic acid and the cognate Ionotropic receptor 75b (Ir75b) in odor-evoked oviposition. Through receptor exchange in D. melanogaster, we provide evidence for a causal contribution of odor-tuning changes in Ir75b to the evolution of D. sechellia's oviposition behavior.
Topics: Animals; Female; Drosophila melanogaster; Odorants; Oviposition; Specialization; Drosophila
PubMed: 37236992
DOI: 10.1038/s41467-023-38722-z -
Nature Jul 2023Whereas progress has been made in the identification of neural signals related to rapid, cued decisions, less is known about how brains guide and terminate more...
Whereas progress has been made in the identification of neural signals related to rapid, cued decisions, less is known about how brains guide and terminate more ethologically relevant decisions in which an animal's own behaviour governs the options experienced over minutes. Drosophila search for many seconds to minutes for egg-laying sites with high relative value and have neurons, called oviDNs, whose activity fulfills necessity and sufficiency criteria for initiating the egg-deposition motor programme. Here we show that oviDNs express a calcium signal that (1) dips when an egg is internally prepared (ovulated), (2) drifts up and down over seconds to minutes-in a manner influenced by the relative value of substrates-as a fly determines whether to lay an egg and (3) reaches a consistent peak level just before the abdomen bend for egg deposition. This signal is apparent in the cell bodies of oviDNs in the brain and it probably reflects a behaviourally relevant rise-to-threshold process in the ventral nerve cord, where the synaptic terminals of oviDNs are located and where their output can influence behaviour. We provide perturbational evidence that the egg-deposition motor programme is initiated once this process hits a threshold and that subthreshold variation in this process regulates the time spent considering options and, ultimately, the choice taken. Finally, we identify a small recurrent circuit that feeds into oviDNs and show that activity in each of its constituent cell types is required for laying an egg. These results argue that a rise-to-threshold process regulates a relative-value, self-paced decision and provide initial insight into the underlying circuit mechanism for building this process.
Topics: Animals; Female; Calcium Signaling; Decision Making; Drosophila melanogaster; Neural Pathways; Neurons; Oviposition; Presynaptic Terminals; Psychomotor Performance
PubMed: 37407812
DOI: 10.1038/s41586-023-06271-6 -
Viruses Apr 2023Targeting gravid females through chemical lures is a promising strategy in vector control; however, it requires the understanding of the factors susceptible to alter...
Targeting gravid females through chemical lures is a promising strategy in vector control; however, it requires the understanding of the factors susceptible to alter female oviposition behavior. Here, we evaluated the effect of infection with chikungunya virus (CHIKV) and the number of gonotrophic cycles (GCs) on oviposition activity in . Dual choice oviposition assays were performed, where dodecanoic acid, pentadecanoic acid, -heneicosane and a (Børgesen) Børgesen extract were tested in uninfected females and females infected with CHIKV, at the 1st and 2nd GC. Infected females displayed a lower percentage of oviposition and a higher number of eggs laid at the 1st GC. Then, the combined effects of GC and CHIKV were observed on oviposition preferences, with a chemical-dependent effect. For instance, the deterrent effect of -heneicosane and pentadecanoic acid increased at the 2nd GC in infected females. These results allow for a deeper understanding of the mechanisms involved in oviposition site selection and highlight the need for taking into account physiological stage changes to increase the control programs' efficacy.
Topics: Animals; Female; Oviposition; Chikungunya Fever; Aedes; Mosquito Vectors; Chikungunya virus
PubMed: 37243130
DOI: 10.3390/v15051043 -
Journal of Evolutionary Biology Jan 2023In phytophagous insects, oviposition behaviour is an important component of habitat selection and, given the multiplicity of genetic and environmental factors affecting...
In phytophagous insects, oviposition behaviour is an important component of habitat selection and, given the multiplicity of genetic and environmental factors affecting its expression, is defined as a complex character resulting from the sum of interdependent traits. Here, we study two components of egg-laying behaviour: oviposition acceptance (OA) and oviposition preference (OP) in Drosophila melanogaster using three natural fruits as resources (grape, tomato and orange) by means of no-choice and two-choice experiments, respectively. This experimental design allowed us to show that the results obtained in two-choice assays (OP) cannot be accounted for by those resulting from no-choice assays (OA). Since the genomes of all lines used are completely sequenced, we perform a genome-wide association study to identify and characterize the genetic underpinnings of these oviposition behaviour traits. The analyses revealed different candidate genes affecting natural genetic variation of both OA and OP traits. Moreover, our results suggest behavioural and genetic decoupling between OA and OP and that egg-laying behaviour is plastic and context-dependent. Such independence in the genetic architectures of OA and OP variation may influence different aspects of oviposition behaviour, including plasticity, canalization, host shift and maintenance of genetic variability, which contributes to the adoption of adaptive strategies during habitat selection.
Topics: Animals; Female; Drosophila melanogaster; Fruit; Oviposition; Genome-Wide Association Study
PubMed: 36357966
DOI: 10.1111/jeb.14109 -
Scientific Reports Jan 2022The ability to cryopreserve mosquitoes would revolutionize work on these vectors of major human infectious diseases by conserving stocks, new isolates, lab-bred strains,...
The ability to cryopreserve mosquitoes would revolutionize work on these vectors of major human infectious diseases by conserving stocks, new isolates, lab-bred strains, and transgenic lines that currently require continuous life cycle maintenance. Efforts over several decades to develop a method for cryopreservation have, until now, been fruitless: we describe here a method for the cryopreservation of Anopheles stephensi embryos yielding hatch rates of ~ 25%, stable for > 5 years. Hatched larvae developed into fertile, fecund adults and blood-fed females, produced fully viable second generation eggs, that could be infected with Plasmodium falciparum at high intensities. The key components of the cryopreservation method are: embryos at 15-30 min post oviposition, two incubation steps in 100% deuterated methanol at - 7 °C and - 14.5 °C, and rapid cooling. Eggs are recovered by rapid warming with concomitant dilution of cryoprotectant. Eggs of genetically modified A. stephensi and of A. gambiae were also successfully cryopreserved. This enabling methodology will allow long-term conservation of mosquitoes as well as acceleration of genetic studies and facilitation of mass storage of anopheline mosquitoes for release programs.
Topics: Animals; Anopheles; Cryopreservation; Cryoprotective Agents; Embryo, Nonmammalian; Larva; Oviposition; Plasmodium falciparum
PubMed: 34997079
DOI: 10.1038/s41598-021-04113-x -
PloS One 2022Modeling oviposition as a function of female insect age, temperature, and host plant suitability may provide valuable insight into insect population growth of...
Modeling oviposition as a function of female insect age, temperature, and host plant suitability may provide valuable insight into insect population growth of polyphagous insect pests at a landscape level. In this study, we quantified oviposition by beet leafhoppers, Circulifer (= Neoaliturus) tenellus (Baker) (Hemiptera: Cicadellidae), on four common non-agricultural host plant species [Erodium cicutarium (L.) L'Hér. (Geraniaceae), Kochia scoparia (L.) Schrader (Amaranthaceae), Plantago ovata Forsskál (Plantaginaceae), and Salsola tragus L. (Amaranthaceae)] at two constant temperature conditions. Additionally, temperature-based oviposition models for each host plant species were validated, under semi-field and greenhouse conditions. We found that K. scoparia was the most suitable host plant, and optimal temperature for oviposition was estimated to be 30.6°C. Accordingly, beet leafhoppers appear to be well-adapted to high-temperature conditions, so increasing temperatures due to climate change may favor population growth in non-agricultural areas. Maximum total fecundity (Rm) was used as an indicator of relative suitability of host plants. S. tragus has been considered an important non-agricultural host plant, however, we found that S. tragus and E. cicutarium have lower Rm compared to K. scoparia and P. ovata. The combination of detailed experimental oviposition bioassays, modeling, and model validation is considered widely relevant and applicable to host plant assessments and modeling of population dynamics of other polyphagous insect pests.
Topics: Animals; Beta vulgaris; Female; Fertility; Hemiptera; Moths; Oviposition; Plants; Temperature
PubMed: 36054184
DOI: 10.1371/journal.pone.0274003 -
Scientific Reports Sep 2020Oviposition by Gasterophilus pecorum on shoot tips of Stipa caucasica is a key determinant of its severe infection of the reintroduced Przewalski's horse (Equus...
Oviposition by Gasterophilus pecorum on shoot tips of Stipa caucasica is a key determinant of its severe infection of the reintroduced Przewalski's horse (Equus przewalskii). Volatiles in shoots of grasses on which Przewalski's horse feeds, including S. caucasica at preoviposition, oviposition, and postoviposition stages of G. pecorum, S. caucasica, Stipa orientalis, and Ceratoides latens at the oviposition stage, and S. caucasica in various growth periods, were collected by dynamic headspace adsorption and analyzed by automatic thermal desorption gas chromatography-mass spectrometry. Among five volatiles with highest relative contents under three sets of conditions, caprolactam and 3-hexen-1-ol,(Z)- were common to all samples. Caprolactam was highest in C. latens at oviposition stage of G. pecorum and lowest in S. caucasica at postoviposition stage, and that of 3-hexen-1-ol,(Z)- was lowest in C. latens and highest in S. caucasica at its oviposition stage. Particularly, in S. caucasica during the three oviposition phenological stages of G. pecorum, 3-hexen-1-ol,acetate,(Z)-, 2(5H)-furanone,5-ethyl-, and 3-hexen-1-ol,acetate,(E)- were unique, respectively, to the preoviposition, oviposition, and postoviposition stages; in three plant species during the oviposition stage of G. pecorum, 3-hexen-1-ol,acetate,(Z)-, 3-hexenal, and 1-hexanol were unique to S. orientalis, acetic acid, hexanal, and 2(5H)-furanone,5-ethyl- to S. caucasica, and 1,3,6-octatriene,3,7-dimethyl-, cis-3-hexenyl isovalerate, and acetic acid hexyl ester to C. latens; in S. caucasica, 2-undecanone,6,10-dimethyl- was unique to the early growth period, acetic acid and 2(5H)-furanone,5-ethyl- to the flourishing growth period, and 3-hexen-1-ol,acetate,(Z)- and 1,3,6-octatriene,3,7-dimethyl- to the late growth period. Furthermore, substances specific to S. orientalis and C. latens were also present in S. caucasica, except at oviposition stage. Our findings will facilitate studies on G. pecorum's adaptation to the arid desert steppe and its future control.
Topics: Adaptation, Physiological; Animals; Diptera; Gas Chromatography-Mass Spectrometry; Oviposition; Plant Extracts; Plant Shoots; Poaceae; Volatile Organic Compounds
PubMed: 32978441
DOI: 10.1038/s41598-020-72378-9 -
Chimia Nov 2022Insect eggs deposited on plants constitute a threat that has led to the evolution of sophisticated defenses. The interactions between insect eggs and plants are governed...
Insect eggs deposited on plants constitute a threat that has led to the evolution of sophisticated defenses. The interactions between insect eggs and plants are governed by a diverse variety of chemicals that inform butterflies about suitable hosts, repel gravid females, alert plants about the presence of an egg, act as signal molecules to induce defenses, directly impair egg development, and indirectly attract egg parasitoids. In recent years, significant progress has been made on the chemical identification, perception and role of compounds associated with oviposition. Knowledge on the genetic basis of oviposition-induced responses is also accumulating. An emerging theme is that insect eggs are not passive structures on leaves but induce complex responses that result from million years of coevolution.
Topics: Female; Animals; Butterflies; Insecta; Oviposition; Plant Leaves; Plants
PubMed: 38069786
DOI: 10.2533/chimia.2022.914