Transcriptomic response of male Anastrepha fraterculus (Diptera: Tephritidae) to sexual stimulation by host plant volatiles

SILVINA ANAHÍ BELLIARD; JUAN HURTADO; SANTIAGO REVALE; DIEGO SEGURA

Congreso; VII Congress of The Latin American Association of Chemical Ecology; 2023

Anastrepha fraterculus is one of the main fruit pests in South America. Previous studies revealed thatvolatiles from guava, a likely ancestral host, stimulate courtship behavior and mating in A. fraterculus males.As the sterile insect technique is under development for this species, the exposure to guava volatiles couldbe incorporated as a pre-release treatment to increase the sexual competitiveness of sterile males. However,the mechanisms underlying this effect are still unknown. Here, we explore the impact of exposure to guavavolatiles on the gene expression profiling of the adult male’s head. We extracted RNA from ten pools of tenmale heads that were dissected in the morning, the time of day of greatest sexual activity. Five of thesesamples were obtained from males previously exposed to volatiles from guava essential oil (exposed males);the other five were obtained from non-exposed males (control males). cDNA libraries constructed frommRNA were sequenced on Illumina NovaSeq 6000 to obtain 2x150 paired-end reads. Then, we performedde novo assembling and differential expression analysis to determine which genes responded to thetreatment. At last, we conducted functional annotation and enrichment analysis to find over- and under-represented GO terms. The final assembly consisted of 191,556 transcripts; 19,766 were associated with atleast one GO term and 4,183 had at least one BLASTX Hit to Diptera proteins. We found 362 differentiallyexpressed genes (FDR < 0.01 and |FC| > 2), 161 of which were over-expressed in exposed males and 201in non-exposed males. The exposure to volatiles from guava oil particularly affected the expression of genesrelated to 1) neuronal signaling mediated by nitric oxide, which may underline the integration of internaland external signals, and 2) polysaccharide catabolism, which may help sustain energetic requirements ofthe increased courtship activity.