2 research outputs found
Female melon fruit flies, Zeugodacus cucurbitae, are attracted to a synthetic chemical blend based on male epicuticular components
The melon fly, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae), is considered to be the most destructive pest of melons and other related cucurbit crops worldwide. Despite the potential of behaviour-based control strategies, little is known about the mechanisms involved in female mate choice. Herein, we investigated the production and chemoreception of cuticular hydrocarbons in both sexes of Z. cucurbitae, and the behavioural responses they induce. We studied the epicuticular composition of virgin males and females, using two-dimensional gas chromatography coupled with mass spectrometric detection. Data were interpreted using multivariate factorial analysis. The differentiation of chemical profiles was consistently observed over time. In young individuals, the chemical profiles did not differ between sexes, while sex-specific differences were noted in mature flies. The fly olfactory sensitivity to these compounds was explored using gas chromatography combined with chopped triple electroantennography and electropalpography detectors. This extensive exploration of the pest olfactory sensitivity highlighted three compounds produced by the male. When blended, they induced a robust positive response in unmated naive females in a six-choice olfactometer. The responsiveness of other Tephritidae species (a polyphagous species Bactrocera dorsalis (Hendel) and the cucurbit specialist Dacus demmerezi (Bezzi)) to whole body extracts of Z. cucurbitae was also investigated. Our findings showed that Z. cucurbitae uses species-specific olfactory receptors to detect male produced compounds. In addition, the palps were sensitive to a female-specific component, 1,7-dioxaspiro[5.5]undecane, which the males produce in minute quantities. Overall, this study provides a starting point for a pheromone-based tephritid lure that targets unmated females. The potential implications for pest management are discussed
Specific Inhibitors of HIV Capsid Assembly Binding to the C‑Terminal Domain of the Capsid Protein: Evaluation of 2‑Arylquinazolines as Potential Antiviral Compounds
Assembly
of human immunodeficiency virus (HIV-1) represents an
attractive target for antiretroviral therapy which is not exploited
by currently available drugs. We established high-throughput screening
for assembly inhibitors based on competition of small molecules for
the binding of a known dodecapeptide assembly inhibitor to the C-terminal
domain of HIV-1 CA (capsid). Screening of >70000 compounds from
different
libraries identified 2-arylquinazolines as low micromolecular inhibitors
of HIV-1 capsid assembly. We prepared focused libraries of modified
2-arylquinazolines and tested their capacity to bind HIV-1 CA to compete
with the known peptide inhibitor and to prevent the replication of
HIV-1 in tissue culture. Some of the compounds showed potent binding
to the C-terminal domain of CA and were found to block viral replication
at low micromolar concentrations