eIF3 subunit m regulates blood meal digestion in Rhodnius prolixus affecting ecdysis, reproduction and survival

AMEIJEIRAS, PILAR; CAPRIOTTI, NATALIA; ONS, SHEILA; OLIVEIRA, PEDRO L.; MARCOS, STERKEL

La Plata

Congreso; II Congress of the Latin American Society for Vector Ecology; 2022

Sociedad Latinoamericana de Ecología de Vectores

In triatomines, blood-feeding triggers many physiologicalprocesses, including post-embryonic development andreproduction. Different feeding habits, such as hematophagy,can shape gene functions to meet the challenges of each typeof diet. A comparison of transcriptomic and proteomic dataindicates that post-transcriptional regulation of gene expressionis crucial in triatomines, so we evaluated the impact of silencingof the eukaryotic translation initiation factor 3 subunit m (eIF3m)in Rhodnius prolixus physiology. In this work we used insects toevaluate oviposition, eclosion, survival and ecdysis rate. Weused RNAi to determine loss-of-function phenotypes, applyingtechniques like RNA isolation and complementary DNA (cDNA)synthesis, synthesis of double-stranded RNA (dsRNA),quantitative polymerase chain reaction (qPCR), haemoglobinquantification, protein content measurement in ovaries andimmunohistochemistry. eIF3m knockdown in the blood-feederR. prolixus caused a reduction in the digestion rate affecting theprocesses triggered by the blood meal, such as reproduction infemales and ecdysis in the nymph. Because oogenesis wasblocked, females were more resistant to starvation and survivedas long as the males after a blood meal. In nymphs, eIF3msilencing caused premature death and absence of ecdysis. Thephenotypes observed in R. prolixus are different from thosepreviously described upon eIF3m knockdown in D.melanogaster and are similar to those described upon DR inother (non-hematophagous) organisms.