Arrest of oogenesis in the bug Rhodnius prolixus challenged with the fungus Aspergillus niger is mediated by immune response-derived PGE2

Medeiros, Marcelo N.; Belmonte, Rodrigo; Soares, Bruno César C.; Medeiros, Luciano Neves de; Canetti, Cláudio; Freire-de-Lima, Célio Geraldo; Maya‐Monteiro, Clarissa M.; Bozza, Patrı́cia T.; Almeida, Igor C.; Masuda, Hatisaburo; Kurtenbach, Eleonora; Machado, Ednildo A.

doi:10.1016/j.jinsphys.2008.10.019

Cited by 19 publications

(10 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Hemiptera, follicular atresia has been investigated in Rhodnius prolixus and Dipetalogaster maxima, both Chagas Disease vectors. In R. prolixus, follicle atresia is triggered by the immune response elicited by the direct injection of a non-pathogenic fungus and Zymosan-A, imposing a major arrest of oogenesis [21]. R. prolixus atretic oocytes present organelles with the typical morphology of autophagic vacuoles, acidified yolk organelles, and an increase in hydrolase activities (which are known to be involved in the degradation of the yolk) [22].…”

Section: Introductionmentioning

confidence: 99%

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

et al. 2020

View full text Add to dashboard Cite

Follicular atresia is the mechanism by which the oocyte contents are degraded during oogenesis in response to stress conditions, allowing the energetic resources stored in the developing oocytes to be reallocated to optimize female fitness. Autophagy is a conserved intracellular degradation pathway where double-membrane vesicles are formed around target organelles leading to their degradation after lysosome fusion. The autophagy-related protein 8 (ATG8) is conjugated to the autophagic membrane and has a key role in the elongation and closure of the autophagosome. Here we identified one single isoform of ATG8 in the genome of the insect vector of Chagas Disease Rhodnius prolixus (RpATG8) and found that it is highly expressed in the ovary during vitellogenesis. Accordingly, autophagosomes were detected in the vitellogenic oocytes, as seen by immunoblotting and electron microscopy. To test if autophagosomes were important for follicular atresia, we silenced RpATG8 and elicited atresia in vitellogenic females by Zymosan-A injections. We found that silenced females were still able to trigger the same levels of follicle atresia, and that their atretic oocytes presented a characteristic morphology, with accumulated brown aggregates. Regardless of the difference in morphology, RpATG8-silenced atretic oocytes presented the same levels of protein, TAG and PolyP, as detected in control atretic oocytes, as well as the same levels of acidification of the yolk organelles. Because follicular atresia has the ultimate goal of restoring female fitness, we tested if RpATG8-silenced atresia would result in female physiology and behavior changes. Under insectarium conditions, we found that atresia-induced control and RpATG8-silenced females present no changes in blood meal digestion, survival, oviposition, TAG content in the fat body, haemolymph amino acid levels and overall locomotor activity. Altogether, we found that autophagosomes are formed during oogenesis and that the silencing of RpATG8 impairs autophagosome biogenesis in the PLOS Neglected Tropical Diseases | https://doi.

show abstract

Section: Introductionmentioning

confidence: 99%

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In S. exigua , RNAi of PGES2 expression can impair its egg‐laying behavior, suggesting that PGE 2 can mediate oviposition behavior of females (Ahmed, Stanley, & Kim, ). PGE 2 can also mediate events in oocyte development of some species including Rhodnius prolixus (Medeiros et al, ). With respect to oocyte development, PGs can mediate chorion production in Bombyx mori and D. melanogaster by coordinating expression of different chorion genes (Machado et al, ; Tootle, Williams, Hubb, Frederick, & Spradling, ).…”

Section: Discussionmentioning

confidence: 99%

Toll/IMD signal pathways mediate cellular immune responses via induction of intracellular PLA₂ expression

Sajjadian

Vatanparast

Kim

2019

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

show abstract

“…In the beet armyworm, Spodoptera exigua , PGE 2 mediate both previtellogenic development and choriogenesis (Abdullah & Kim, ). PGE 2 also influences the development of some species, including the kissing bug, Rhodnius prolixus (de Medeiros et al, ). In excretion, fluid secretion from hemolymph to Malpighian tubule lumen depends on PGs in the forest ant, Formica polytena (Van Kerkhove, Pirotte, Petzel, & Stanley‐Samuelson, ).…”

Section: Introductionmentioning

confidence: 99%

PGE₂ mediates cytoskeletal rearrangement of hemocytes via Cdc42, a small G protein, to activate actin‐remodeling factors in Spodoptera exigua (Lepidoptera: Noctuidae)

Ahmed

Kim

2019

Arch Insect Biochem Physiol

View full text Add to dashboard Cite

Prostaglandin E 2 (PGE 2 ) mediates cellular immune responses in insects by stimulating hemocyte-spreading behavior that is driven by actin remodeling to form filopodial or lamellipodial cytoplasmic extensions. In Spodoptera exigua (Lepidoptera: Noctuidae), Cdc42, a small G protein, played a crucial role in mediating PGE 2 signal on hemocyte-spreading behavior. Hemocyte-spreading behavior requires actin cytoskeletal rearrangement. A plethora of actin-related proteins have been predicted to have functional links with Cdc42. Here, we selected four actinassociated genes (Actin-related protein 2 [Arp2], Profilin, Cofilin, and Fascin) and evaluated their influences on cytoskeletal rearrangement in S. exigua. Bioinformatic analysis confirmed their gene identities. Transcript analysis using reverse-transcription polymerase chain reaction indicated that all four actin-associated genes were expressed in most developmental stages, showing high expression levels in larval hemocytes. RNA interference (RNAi) against these genes was performed by injecting double-stranded RNA (dsRNA) to hemocoel. Under RNAi condition, the hemocyte-spreading behavior was significantly impaired except for dsRNA treatment against Cofilin, an actindepolymerizing factor. Alteration of cytoskeletal rearrangement appeared to vary after different RNAi treatments. RNAi against Arp2 markedly suppressed lamellipodial extension while RNAi against Profilin or Fascin adversely influenced filopodial extension. RNAi of these actin-associated factors prevented cellular immune responses measured by nodule formation against bacterial challenge. Under RNAi conditions, addition of PGE 2 did not well induce hemocyte-spreading behavior, suggesting that these actin-associated factors might act downstream of the hormone signaling pathway. These results suggest that PGE 2 can mediate hemocyte-spreading behavior via Cdc42 to activate downstream actin polymerization/branching/ bundling factors, thus inducing actin cytoskeletal rearrangement. K E Y W O R D S Arp2, cofilin, fascin, PGE2, profilin, Spodoptera exigua

show abstract

Arrest of oogenesis in the bug Rhodnius prolixus challenged with the fungus Aspergillus niger is mediated by immune response-derived PGE2

Cited by 19 publications

References 42 publications

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

Toll/IMD signal pathways mediate cellular immune responses via induction of intracellular PLA₂ expression

PGE₂ mediates cytoskeletal rearrangement of hemocytes via Cdc42, a small G protein, to activate actin‐remodeling factors in Spodoptera exigua (Lepidoptera: Noctuidae)

Contact Info

Product

Resources

About

Arrest of oogenesis in the bug Rhodnius prolixus challenged with the fungus Aspergillus niger is mediated by immune response-derived PGE2

Cited by 19 publications

References 42 publications

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

Silencing of RpATG8 impairs the biogenesis of maternal autophagosomes in vitellogenic oocytes, but does not interrupt follicular atresia in the insect vector Rhodnius prolixus

Toll/IMD signal pathways mediate cellular immune responses via induction of intracellular PLA2 expression

PGE2 mediates cytoskeletal rearrangement of hemocytes via Cdc42, a small G protein, to activate actin‐remodeling factors in Spodoptera exigua (Lepidoptera: Noctuidae)

Contact Info

Product

Resources

About

Toll/IMD signal pathways mediate cellular immune responses via induction of intracellular PLA₂ expression

PGE₂ mediates cytoskeletal rearrangement of hemocytes via Cdc42, a small G protein, to activate actin‐remodeling factors in Spodoptera exigua (Lepidoptera: Noctuidae)