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Changes in tsetse physiology after suppression of aquaporins. (A) qPCR expression of aquaporins (gmmdripa, gmmdripb and gmmaqp5) after knockdown utilizing siRNA injection. Data represent the mean ± SE for three samples and was normalized to tubulin. (B) Rate of water loss (%/h, diuresis plus cuticular and respiratory water loss) after siRNA injection and a subsequent bloodmeal. The combined injection group received all three siRNAs for dripa, dripb and aqp5. Data represent the mean ± SE of three groups of 6 flies. (C) Images of bloodfed flies after injection of siGFP or combined siAQPs showing increased size due to delayed water loss (diuresis along with cuticular and respiratory water loss). (D) qPCR expression of transcripts for antioxidant enzymes (Mn/Fe superoxide dismutase, Mn/Fe sod; Cu/Zn superoxide dismutase, Cu/Zn sod; catalase, cat) 6 h after blood feeding after combined knockdown of AQPs. Data represent the mean ± SE for three samples and was normalized to tubulin. (E) Average duration of survival under dehydrating conditions following blood feeding after suppression by siRNA injection. Each point represents mean ± SE of five groups of 10 flies. Black point represents the mean. (F) Heat tolerance following knockdown of aqps. n Data are presented as mean ± SE of three groups of 6 flies. Black point represents the mean. * indicates that the value is significantly different (*P<0.05; **, P<0.01; ***, P<0.001) than control. siGFP, short-interfering green fluorescent protein that serves as a control.
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Tsetse flies undergo drastic fluctuations in their water content throughout their adult life history due to events such as blood feeding, dehydration and lactation, an essential feature of the viviparous reproductive biology of tsetse. Aquaporins (AQPs) are transmembrane proteins that allow water and other solutes to permeate through cellular membr...
Citations
... Tsetse flies (Glossina genus) are vectors of African trypanosomes causing sleeping sickness in humans and nagana in livestock, with devastating public health and economic effects in Africa [181,182]. Reproductive biology in these species has been widely investigated [55,[183][184][185][186][187][188][189][190][191][192][193][194][195][196][197][198][199], not only to develop novel tsetse control approaches but also for its unique features related to adenotrophic viviparity (i.e. maternal nourishment of the progeny in the uterus followed by live birth of the larva) [200]. ...
Pathogens can influence the physiology and behavior of both animal and plant hosts in a manner that promotes their own transmission and dispersal. Recent research focusing on insects has revealed that these manipulations can extend to the production of pheromones, which are pivotal in chemical communication. This review provides an overview of the current state of research and available data concerning the impacts of bacterial, viral, fungal, and eukaryotic pathogens on chemical communication across different insect orders. While our understanding of the influence of pathogenic bacteria on host chemical profiles is still limited, viral infections have been shown to induce behavioral changes in the host, such as altered pheromone production, olfaction, and locomotion. Entomopathogenic fungi affect host chemical communication by manipulating cuticular hydrocarbons and pheromone production, while various eukaryotic parasites have been observed to influence insect behavior by affecting the production of pheromones and other chemical cues. The effects induced by these infections are explored in the context of the evolutionary advantages they confer to the pathogen. The molecular mechanisms governing the observed pathogen-mediated behavioral changes, as well as the dynamic and mutually influential relationships between the pathogen and its host, are still poorly understood. A deeper comprehension of these mechanisms will prove invaluable in identifying novel targets in the perspective of practical applications aimed at controlling detrimental insect species.
... Aquaporins (AQPs) are a family of membrane proteins that play a crucial role in maintaining water balance by facilitating the movement of water across cellular membranes [15,16]. In the context of milk synthesis and production, AQPs are involved in the transport of water and small solutes across mammary endothelial barriers [16], While the role of AQPs in mammary epithelial cells is well-established, their presence and potential function in blood vessels raise intriguing possibilities. ...
Herbal galactagogues have been widely used as a treatment for postpartum hypogalactia due to the potential side effects associated with pharmacological therapy. Tri-Than-Thip (Tri-TT) is a Thai herbal medicine remedy that contains three main components: Cassia fistula, Pithecellobium dulce, and Ficus benjamina. These components are believed to have properties that contribute to milk production. However, despite the traditional use of Tri-TT, there is a lack of academic evidence supporting its efficacy in enhancing milk production. Therefore, the purpose of this study was to investigate the effect of Tri-TT on milk production and determine if it has a galactagogue effect. The weight suckle weight model was used to determine total milk production in lactating rats, while histological analysis was performed to assess the alveolar diameter of the mammary gland. The findings of this study revealed a significant increase in total milk production among lactating rats treated with 500 mg/kg of Tri-TT, compared to the control group. Furthermore, both the Tri-TT and Domperidone-treated groups exhibited a larger alveolar diameter of the mammary gland in comparison to the control group. In summary, these findings provide supportive evidence for the galactagogue activity of Tri-TT. The observed enhancement in milk production may be associated with Tri-TT could potentially be attributed to its ability to widen the alveolar diameter of the mammary gland, thereby facilitating increased milk volume.
... RNAi of AQP1 of Bemisia tabaci through an artifi cial diet resulted in 70% reduction in gene expression and 84% mortality by d6 post-feeding (Vyas et al., 2017). Similarly, RNAi of AQPs was successfully achieved in other insects such as Acyrthosiphon pisum (Shakesby et al., 2009), Myzus persicae and Bactericera cockerelli (Tzin et al., 2015), Glossina morsitans morsitans (Benoit et al., 2014) and few others. Regarding Lepidoptera, we found only one study reporting RNAi of Se-AQP1 in S. exigua (Ahmed & Kim, 2019). ...
Aquaporins (AQPs) are integral membrane proteins that can transport water and small molecules across cell membranes in organisms. In a previous report, we identified an AQP (SlAQP1) gene of the cotton leafworm, Spodoptera littoralis. In the current study, we identify and characterize two more SlAQP genes and their developmental and tissues expression. Predicted amino acid sequence and phylogenetic analysis revealed that SlAQP2 is a glycerol channel belonging to the insect specific Eglp subfamily, whereas SlAQP3 is a water specific channel belonging to the Prip subfamily. SlAQP2 expression was detected mainly in the first four larval instars and adult males, whereas SlAQP3 was detected in all developmental stages. SlAQP2 gene expression was mainly detected in larval midgut and Malpighian tubules and adult male testes, whereas SlAQP3 was detected in all the tissues tested. RNAi mediated knockdown of each gene separately resulted in deleterious effects including larval and pupal mortality, deformed pupae and adults and prolonged development. Results were confirmed using qRT-PCR, which revealed downregulation of both genes after injection of larvae with gene specific dsRNA. Our results confirm the presence of Prip and Eglp AQPs in S. littoralis and suggest that Eglp has a role in male reproductive ability.
... Increased excretion rate by aquaporins is a mechanism by which insects develop resistance to insecticides [10,11]. In addition to excretion, aquaporins also regulate reproduction [12][13][14][15] and are used by many insects to combat environmental stresses, such as low temperatures and drought [16][17][18][19]. ...
Rhyzopertha dominica Prip (RdPrip) cDNA was cloned (GenBank accession no. OK318454), and the encoded 276-amino-acid protein indicated the typical aquaporin structure, including six transmembrane regions and two NPA motifs. The developmental and tissue profiles of RdPrip transcription were determined. RdPrip was highly transcribed in female adults, followed by larvae, pupae, and male adults. The transcriptional expression levels of RdPrip were significantly high in the ovary and hindgut (including cryptonephridial systems) compared with the foregut, testis, midgut, and Malpighian tubules. Knockdown of RdPrip in female adults did not decrease fecundity, but significantly decreased the hatching rate of eggs laid by the females. The results suggest that RdPrip functions in embryonic development, not in egg formation. In addition, the transcriptional expression level of RdPrip was lower in the spinosad-resistant strain than in the susceptible one, and the resistant strain produced fewer progeny than the susceptible strain did. These studies support the functional role of RdPrip in female reproduction. The absence of significant mortality reduction in the R. dominica exposed to spinosad after RdPrip RNAi suggests that other aquaporins that were not knocked down may exist for the excretion of metabolized pesticides.
... Mosquitoes and coleopteran water beetles Huestis et al., 2012;Hidalgo et al., 2018;Pallarés et al., 2016 Spiracle size Reduction Thick hairs surrounding spiracle obstruct spiracular opening, and reduced spiracle size limit body water loss Mosquitoes, black flies and tsetse flies Arcaz et al., 2016;Bursell, 1957;Mamai et al., 2016;Shipp et al., 1987 Heart contraction rate Reduction Decrease in haemolymph pressure and elevated mRNA level of nitric oxide synthase (NOS), which suppresses the heart rate Mosquitoes, Drosophila and other arthropods Albers and Bradley, 2004;Boerjan et al., 2010;Ellison et al., 2015 Reproductive capability Reduction Limited distribution of water suppresses oviposition time, egg production and changes oviposition patterns Mosquitoes and tsetse flies Benoit et al., 2014b;Costa et al., 2010;Hagan et al., 2018 Survival Haematophagy poses a challenge to mosquitoes, as products after blood digestion can yield cellular deleterious effects. Following a blood meal, MTs excrete 40% of the ingested blood, a process which is regulated by hormones that increase diuresis at the MT level (Dana et al., 2005;Stobbart, 1977;Williams et al., 1983). ...
... All readings were obtained on four biological replicates (two flies merged per replicate) normalized to tsetse tubulin expression levels. CFX Manager software version 3.1 (Biorad) was used to quantify the transcript abundance of each gene and conducted according to methods developed in previous studies [12,23]. All statistics were conducted with the use of R packages (3.6.3). ...
The ingestion of blood represents a significant burden that immediately increases water, oxidative, and thermal stress, but provides a significant nutrient source to generate resources necessary for the development of progeny. Thermal stress has been assumed to solely be a negative byproduct that has to be alleviated to prevent stress. Here, we examined if the short thermal bouts incurred during a warm blood meal are beneficial to reproduction. To do so, we examined the duration of pregnancy and milk gland protein expression in the tsetse fly, Glossina morsitans, that consumed a warm or cool blood meal. We noted that an optimal temperature for blood ingestion yielded a reduction in the duration of pregnancy. This decline in the duration of pregnancy is due to increased rate of blood digestion when consuming warm blood. This increased digestion likely provided more energy that leads to increased expression of transcript for milk-associated proteins. The shorter duration of pregnancy is predicted to yield an increase in population growth compared to those that consume cool or above host temperatures. These studies provide evidence that consumption of a warm blood meal is likely beneficial for specific aspects of vector biology.
... A few organisms do not directly drink water, but rather have unique mechanisms to obtain water from the air (discussed below in Section 5.3) or maintain their water budget from food sources (13,76). When hydration is limited to feeding, most species consume water-rich foods, such as blood and plant-based fluids or other wet food sources. ...
Since the transition from water to land, maintaining water balance has been a key challenge for terrestrial arthropods. We explore factors that allow terrestrial arthropods to survive within a variably dry world and how they shape ecological interactions. Detection of water and hydration is critical for maintaining water content. Efficient regulation of internal water content is accomplished by excretory and osmoregulatory systems that balance water intake and loss. Biochemical and physiological responses are necessary as water content declines to prevent and repair the damage that occurs during dehydration. Desiccation avoidance can occur seasonally or daily via a move to more favorable areas. Dehydration and its avoidance have ecological impacts that extend beyond a single species to alter trophic interactions. As climate changes, evolutionary and ecological processes will be critical to species survival during drought.
Expected final online publication date for the Annual Review of Entomology, Volume 68 is January 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
... Osmoregulation is a key physiological function in homopterans like aphids and whiteflies, which helps in maintaining fluid balance in the process of feeding and excretion. Two transmembrane proteins Calcitonin and Aquaporin are known for their involvement in osmoregulation in B. tabaci (Furuya et al. 2000, Benoit et al. 2014. The expression of these two genes and qualitative fluid analysis was indicative of no visible negative impact of antibiotic feeding on osmoregulation. ...
Insects often coevolved with their mutualistic partners such as gut endosymbionts, which play a key in the physiology of host. Studies on such interactions between Bemisia tabaci and its primary and secondary endosymbionts have gained importance due to their indispensable roles in the biology of this insect. Present study reports the predominance of two secondary endosymbionts, Arsenophonus and Cardinium in the Asia II-1 genetic group of whitefly and elucidates their role in the transmission of its vectored Cotton leaf curl virus. Selective elimination of endosymbionts was optimized using serial concentration of ampicillin, chlor-amphenicol, kanamycin, tetracycline, and rifampicin administered to viruliferous whiteflies through sucrose diet. Primary endosymbiont, Portiera was unresponsive to all the antibiotics, however, rifampicin and tetra-cycline at 90 μg/ml selectively eliminated Arsenophonus from the whitefly. Elimination of Arsenophonus resulted in significant decrease in virus titer from viruliferous whitefly, further the CLCuV transmission efficiency of these whiteflies was significantly reduced compared to the control flies. Secondary endosymbiont, Cardinium could not be eliminated completely even with higher concentrations of antibiotics. Based on the findings, Arsenophonus plays a key role in the retention and transmission of CLCuV in the Asia II-1 genetic group of B. tabaci, while the role of Cardinium could not be established due to its unresponsiveness to antibiotics.
... The partial penetrance of RNAi knockdown phenotypes, combined with the observation that two distinct aquaporin encoding genes are involved, suggests that there may be functional redundancy between these aquaporins. Such redundancy has previously been observed in the tsetse fly, where simultaneous downregulation of multiple aquaporins exacerbates the negative effects on female fecundity produced by individual aquaporin knockdowns (Benoit et al., 2014). ...
Neurons utilize plasticity of dendritic arbors as part of a larger suite of adaptive plasticity mechanisms. This explicitly manifests with motoneurons in the Drosophila embryo and larva, where dendritic arbors are exclusively postsynaptic and are used as homeostatic devices, compensating for changes in synaptic input through adapting their growth and connectivity. We recently identified reactive oxygen species (ROS) as novel plasticity signals instrumental in this form of dendritic adjustment. ROS correlate with levels of neuronal activity and negatively regulate dendritic arbor size. Here, we investigated NADPH oxidases as potential sources of such activity-regulated ROS and implicate Dual Oxidase (but not Nox), which generates hydrogen peroxide extracellularly. We further show that the aquaporins Bib and Drip, but not Prip, are required for activity-regulated ROS-mediated adjustments of dendritic arbor size in motoneurons. These results suggest a model whereby neuronal activity leads to activation of the NADPH oxidase Dual Oxidase, which generates hydrogen peroxide at the extracellular face; aquaporins might then act as conduits that are necessary for these extracellular ROS to be channeled back into the cell where they negatively regulate dendritic arbor size.
... These responses contribute to reduced water loss during desiccation stress. Indeed, knockdown of aquaporins by RNA interference (RNAi) enhances desiccation tolerance in mosquitoes A. gambiae and Aedes aegypti, and in the tsetse fly Glossina morsitans morsitans (Benoit et al., 2014;Drake et al., 2015;Liu et al., 2011). ...
... The reason for this discrepancy is unknown, but it is possibly due to low interspecific crossreactivity of the antibody. Based on expression patterns, Eglp1 and 2 contribute to transport of water, glycerol, and/or urea in the midgut, as proposed in G. m. morsitans (Benoit et al., 2014). The mRNA level of Aqp12L was high in the foregut, midgut, and hindgut in B. antarctica, as found in other insect species (Drake et al., 2010;Benoit et al., 2014). ...
... Based on expression patterns, Eglp1 and 2 contribute to transport of water, glycerol, and/or urea in the midgut, as proposed in G. m. morsitans (Benoit et al., 2014). The mRNA level of Aqp12L was high in the foregut, midgut, and hindgut in B. antarctica, as found in other insect species (Drake et al., 2010;Benoit et al., 2014). Bib mRNAs were detected in the various organs in B. antarctica. ...
Larvae of the Antarctic midge Belgica antarctica Jacobs (Diptera: Chironomidae) are highly tolerant of diverse environmental stresses, including freezing, severe desiccation, and osmotic extremes. Furthermore, dehydration confers subsequent desiccation and freeze tolerance. While a role for aquaporins-channels for water and other solutes-has been proposed in these dehydration processes, the types of aquaporins involved in dehydration-driven stress tolerance remain unknown. In the present study, we investigated expression of six aquaporins (Drip, Prip, Eglp1, Eglp2, Aqp12L, and Bib) in larvae of B. antarctica subjected to under three different dehydration conditions: desiccation, cryoprotective dehydration, and osmotic dehydration. The expression of Drip and Prip was up-regulated under desiccation and cryoprotective dehydration, suggesting a role for these aquaporins in efficient water loss under these dehydration conditions. Conversely, expression of Drip and Prip was down-regulated under osmotic dehydration, suggesting that their expression is suppressed in larvae to combat dehydration. Larval water content was similarly decreased under all three dehydration conditions. Differences in responses of the aquaporins to the three forms of dehydration suggests distinct water management strategies associated with different forms of dehydration stress.
