Pathology of Coelomomyces stegomyiae in adult Aedes aegypti ovaries

1988 ◽  
Vol 66 (5) ◽  
pp. 877-884 ◽  
Author(s):  
Christopher J. Lucarotti ◽  
Marina B. Klein
Keyword(s):  
Plasma Membrane ◽  
Aedes Aegypti ◽  
Adult Female ◽  
Blood Meal ◽  
Egg Development ◽  
Yolk Granules ◽  
Receptor Mediated Endocytosis ◽  
Fungal Hyphae ◽  
Tunica Propria ◽  
Coelomomyces Stegomyiae

Coelomomyces stegomyiae (Chytridiomycetes, Blastocladiales) infection in adult female Aedes aegypti (Diptera, Culicidae) is located primarily in the ovaries. Fungal hyphae do not penetrate the germaria or follicles but instead lie between the tunica propria and epithelial sheath within each ovariole and between the epithelial sheath and the peritoneal sheath of the ovary. Aedes aegypti is an anautogenous mosquito requiring a blood meal for egg development; similarly, fungal hyphae in infected ovaries will not differentiate to form resting sporangia until after the mosquito has taken a blood meal. The fungus restricts receptor-mediated endocytosis of vitellogenin by the plasma membrane of the oocyte so that few, if any, vitellin yolk granules form. Thick-walled resting sporangia have formed 72 h after the blood meal has been taken and these will be oviposited by the females in place of the aborted eggs.

The influence of the brain hormone on retention of blood in the mid-gut of the mosquito Aedes aegypti (L.) III. The involvement of the ovaries and ecdysone

1979 ◽  
Vol 205 (1160) ◽  
pp. 411-421 ◽  
Keyword(s):  
Aedes Aegypti ◽  
Blood Meal ◽  
Ovarian Development ◽  
Neurosecretory Cells ◽  
Direct Result ◽  
Corpus Cardiacum ◽  
Egg Development ◽  
The Brain

Most female mosquitoes require a blood-meal in order to produce mature oöcytes. An egg development neurosecretory hormone (EDNH), which is produced in the medial neurosecretory cells (m. n. c.) of the brain and stored in the corpus cardiacum, is released into the haemolymph following the ingestion of blood and is essential for the promotion of ovarian development to maturity. It has been shown that a factor from the m. n. c., presumably EDNH, is necessary if the blood-meal is to be retained in the mid-gut until the oöcytes approach maturity. The present paper shows that retention is not a direct result of the action of EDNH, but is dependent on the ovaries and may well involve ecdysone. Removal of the ovaries before a blood-meal leads to early haem-defaecation, but delay can be restored by injection of ecdysterone. Sub-threshold feeders and mosquitoes decapitated immediately after the intake of blood, each of which would be expected to eliminate the blood-meal early, also show a delay in the onset of haem-defaecation when injected with ecdysterone. Further, both in ovariectomized insects and sub-threshold feeders the time of onset of haem-defaecation is associated with the dose of ecdysterone given.

scholarly journals Hormone-dependent activation and repression of microRNAs by the ecdysone receptor in the dengue vector mosquito Aedes aegypti

2021 ◽  
Vol 118 (26) ◽  
pp. e2102417118
Author(s):  
Ya-Zhou He ◽  
Emre Aksoy ◽  
Yike Ding ◽  
Alexander S. Raikhel
Keyword(s):  
Aedes Aegypti ◽  
Mirna Expression ◽  
Blood Meal ◽  
Fat Body ◽  
Blood Feeding ◽  
Small Rna Sequencing ◽  
Sequencing Analysis ◽  
Ecdysone Receptor ◽  
Egg Development ◽  
Semialdehyde Dehydrogenase

Female mosquitoes transmit numerous devastating human diseases because they require vertebrate blood meal for egg development. MicroRNAs (miRNAs) play critical roles across multiple reproductive processes in female Aedes aegypti mosquitoes. However, how miRNAs are controlled to coordinate their activity with the demands of mosquito reproduction remains largely unknown. We report that the ecdysone receptor (EcR)–mediated 20-hydroxyecdysone (20E) signaling regulates miRNA expression in female mosquitoes. EcR RNA-interference silencing linked to small RNA-sequencing analysis reveals that EcR not only activates but also represses miRNA expression in the female mosquito fat body, a functional analog of the vertebrate liver. EcR directly represses the expression of clustered miR-275 and miR-305 before blood feeding when the 20E titer is low, whereas it activates their expression in response to the increased 20E titer after a blood meal. Furthermore, we find that SMRTER, an insect analog of the vertebrate nuclear receptor corepressors SMRT and N-CoR, interacts with EcR in a 20E-sensitive manner and is required for EcR-mediated repression of miRNA expression in Ae. aegypti mosquitoes. In addition, we demonstrate that miR-275 and miR-305 directly target glutamate semialdehyde dehydrogenase and AAEL009899, respectively, to facilitate egg development. This study reveals a mechanism for how miRNAs are controlled by the 20E signaling pathway to coordinate their activity with the demands of mosquito reproduction.

The influence of the brain hormone on retention of blood in the mid-gut of the mosquito Aedes aegypti (L.) - II. Early elimination following removal of the medial neurosecretory cells of the brain

1978 ◽  
Vol 202 (1147) ◽  
pp. 307-311 ◽  
Keyword(s):  
Aedes Aegypti ◽  
Oocyte Maturation ◽  
Blood Meal ◽  
Neurosecretory Cells ◽  
Secretory Cells ◽  
Corpus Cardiacum ◽  
Egg Development ◽  
Pars Intercerebralis ◽  
The Brain

Development of the oöcytes beyond the resting stage to maturity in mosquitoes is triggered by an egg development neurosecretory hormone from the brain. This hormone is produced by the medial neurosecretory cells of the pars intercerebralis, and in anautogenous species is stored in the corpus cardiacum until a blood-meal is taken. Removal of the head of the mosquito Aedes aegypti (L.), shortly after completion of a blood-meal, has previously been shown not only to prevent oöcyte maturation, but also to result in early elimination of the blood-meal. The work described in this paper shows that it is a factor originating in the medial neuro­-secretory cells, presumably egg development neurosecretory hormone, which is essential if the blood-meal is to be retained in the mid-gut until the oöcytes are nearing maturity.

Inhibition of clathrin-coated pit assembly by an Eps15 mutant

1999 ◽  
Vol 112 (9) ◽  
pp. 1303-1311 ◽  
Author(s):  
A. Benmerah ◽  
M. Bayrou ◽  
N. Cerf-Bensussan ◽  
A. Dautry-Varsat
Keyword(s):  
Plasma Membrane ◽  
Fusion Protein ◽  
Binding Site ◽  
Specific Marker ◽  
Coated Pits ◽  
Receptor Mediated Endocytosis ◽  
Gfp Fusion Protein ◽  
Protein Encoding ◽  
Homology Domains

Recent data have shown that Eps15, a newly identified component of clathrin-coated pits constitutively associated with the AP-2 complex, is required for receptor-mediated endocytosis. However, its precise function remains unknown. Interestingly, Eps15 contains three EH (Eps15-Homology) domains also found in proteins required for the internalization step of endocytosis in yeast. Results presented here show that EH domains are required for correct coated pit targeting of Eps15. Furthermore, when cells expressed an Eps15 mutant lacking EH domains, the plasma membrane punctate distribution of both AP-2 and clathrin was lost, implying the absence of coated pits. This was further confirmed by the fact that dynamin, a GTPase found in coated pits, was homogeneously redistributed on the plasma membrane and that endocytosis of transferrin, a specific marker of clathrin-dependent endocytosis, was strongly inhibited. Altogether, these results strongly suggest a role for Eps15 in coated pit assembly and more precisely a role for Eps15 in the docking of AP-2 onto the plasma membrane. This hypothesis is supported by the fact that a GFP fusion protein encoding the ear domain of (alpha)-adaptin, the AP-2 binding site for Eps15, was efficiently targeted to plasma membrane coated pits.

scholarly journals Sequential Infection of Aedes aegypti Mosquitoes with Chikungunya Virus and Zika Virus Enhances Early Zika Virus Transmission

Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 177 ◽  
Author(s):  
Tereza Magalhaes ◽  
Alexis Robison ◽  
Michael Young ◽  
William Black ◽  
Brian Foy ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Blood Meal ◽  
Zika Virus ◽  
Chikungunya Virus ◽  
Vector Competence ◽  
Virus Transmission ◽  
Mosquito Vector ◽  
Molecular Aspects ◽  
Virus Interactions ◽  
Sequential Infection

In urban settings, chikungunya, Zika, and dengue viruses are transmitted by Aedes aegypti mosquitoes. Since these viruses co-circulate in several regions, coinfection in humans and vectors may occur, and human coinfections have been frequently reported. Yet, little is known about the molecular aspects of virus interactions within hosts and how they contribute to arbovirus transmission dynamics. We have previously shown that Aedes aegypti exposed to chikungunya and Zika viruses in the same blood meal can become coinfected and transmit both viruses simultaneously. However, mosquitoes may also become coinfected by multiple, sequential feeds on single infected hosts. Therefore, we tested whether sequential infection with chikungunya and Zika viruses impacts mosquito vector competence. We exposed Ae. aegypti mosquitoes first to one virus and 7 days later to the other virus and compared infection, dissemination, and transmission rates between sequentially and single infected groups. We found that coinfection rates were high after sequential exposure and that mosquitoes were able to co-transmit both viruses. Surprisingly, chikungunya virus coinfection enhanced Zika virus transmission 7 days after the second blood meal. Our data demonstrate heterologous arbovirus synergism within mosquitoes, by unknown mechanisms, leading to enhancement of transmission under certain conditions.

scholarly journals Environmental and Genetic Factors Determine Whether the Mosquito Aedes aegypti Lays Eggs Without a Blood Meal

2015 ◽  
Vol 92 (4) ◽  
pp. 715-721 ◽  
Author(s):  
Cristina V. Ariani ◽  
Francis M. Jiggins ◽  
Jewelna Osei-Poku ◽  
Sophia C. L. Smith ◽  
Punita Juneja ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Blood Meal ◽  
Genetic Factors

scholarly journals The Fat Body Transcriptomes of the Yellow Fever Mosquito Aedes aegypti, Pre- and Post- Blood Meal

PLoS ONE ◽  
2011 ◽  
Vol 6 (7) ◽  
pp. e22573 ◽  
Author(s):  
David P. Price ◽  
Vijayaraj Nagarajan ◽  
Alexander Churbanov ◽  
Peter Houde ◽  
Brook Milligan ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Yellow Fever ◽  
Blood Meal ◽  
Fat Body ◽  
Yellow Fever Mosquito

scholarly journals Electrophysiology of the isolated and perfused midgut of adult female yellow fever mosquitoes ( Aedes aegypti )

2010 ◽  
Vol 24 (S1) ◽  
Author(s):  
Horst Onken ◽  
Yolana Fuks ◽  
Melanie Valencia ◽  
Stacia B Moffett ◽  
David F Moffett
Keyword(s):  
Aedes Aegypti ◽  
Yellow Fever ◽  
Adult Female

scholarly journals AP-2/Eps15 Interaction Is Required for Receptor-mediated Endocytosis

1998 ◽  
Vol 140 (5) ◽  
pp. 1055-1062 ◽  
Author(s):  
Alexandre Benmerah ◽  
Christophe Lamaze ◽  
Bernadette Bègue ◽  
Sandra L. Schmid ◽  
Alice Dautry-Varsat ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Fusion Protein ◽  
Binding Sites ◽  
Fluorescent Protein ◽  
Coated Vesicle ◽  
Mutant Form ◽  
A431 Cells ◽  
Coated Pits ◽  
Receptor Mediated Endocytosis ◽  
Terminal Domain

We have previously shown that the protein Eps15 is constitutively associated with the plasma membrane adaptor complex, AP-2, suggesting its possible role in endocytosis. To explore the role of Eps15 and the function of AP-2/Eps15 association in endocytosis, the Eps15 binding domain for AP-2 was precisely delineated. The entire COOH-terminal domain of Eps15 or a mutant form lacking all the AP-2–binding sites was fused to the green fluorescent protein (GFP), and these constructs were transiently transfected in HeLa cells. Overexpression of the fusion protein containing the entire COOH-terminal domain of Eps15 strongly inhibited endocytosis of transferrin, whereas the fusion protein in which the AP-2–binding sites had been deleted had no effect. These results were confirmed in a cell-free assay that uses perforated A431 cells to follow the first steps of coated vesicle formation at the plasma membrane. Addition of Eps15-derived glutathione-S-transferase fusion proteins containing the AP-2–binding site in this assay inhibited not only constitutive endocytosis of transferrin but also ligand-induced endocytosis of epidermal growth factor. This inhibition could be ascribed to a competition between the fusion protein and endogenous Eps15 for AP-2 binding. Altogether, these results show that interaction of Eps15 with AP-2 is required for efficient receptor-mediated endocytosis and thus provide the first evidence that Eps15 is involved in the function of plasma membrane–coated pits.

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