AUTHOR=Nguyen Thu N. M. , Choo Amanda , Baxter Simon W. 

TITLE=Conservation of shibire and RpII215 temperature-sensitive lethal mutations between Drosophila and Bactrocera tryoni

JOURNAL=Frontiers in Insect Science

VOLUME=4

YEAR=2024

URL=https://www.frontiersin.org/journals/insect-science/articles/10.3389/finsc.2024.1249103

DOI=10.3389/finsc.2024.1249103

ISSN=2673-8600

ABSTRACT=<p>The sterile insect technique can suppress and eliminate population outbreaks of the Australian horticultural pest, <italic>Bactrocera tryoni</italic>, the Queensland fruit fly. Sterile males mate with wild females that produce inviable embryos, causing population suppression or elimination. Current sterile insect releases are mixed sex, as the efficient removal of unrequired factory-reared females is not yet possible. In this paper, we assessed the known <italic>Drosophila melanogaster</italic> temperature-sensitive embryonic lethal alleles <italic>shibire</italic> (G268D, <italic>shi<sup>ts1</sup></italic>) and <italic>RNA polymerase II 215</italic> (R977C, <italic>RpII215<sup>ts</sup></italic>) for potential use in developing <italic>B. tryoni</italic> genetic sexing strains (GSS) for the conditional removal of females. Complementation tests in <italic>D. melanogaster</italic> wild-type or temperature-sensitive genetic backgrounds were performed using the GAL4–UAS transgene expression system. A <italic>B. tryoni</italic> wild-type <italic>shibire</italic> isoform partially rescued <italic>Drosophila</italic> temperature lethality at 29°C by improving survivorship to pupation, while expressing <italic>B. tryoni shi<sup>ts1</sup></italic> failed to rescue the lethality, supporting a temperature-sensitive phenotype. Expression of the <italic>B. tryoni RpII215</italic> wild-type protein rescued the lethality of <italic>D. melanogaster RpII215<sup>ts</sup></italic> flies at 29°C. Overexpressing the <italic>B. tryoni RpII215<sup>ts</sup></italic> allele in the <italic>D. melanogaster</italic> wild-type background unexpectedly produced a dominant lethal phenotype at 29°C. The <italic>B. tryoni shibire</italic> and <italic>RpII215</italic> wild-type alleles were able to compensate, to varying degrees, for the function of the <italic>D. melanogaster</italic> temperature-sensitive proteins, supporting functional conservation across species. <italic>Shibire</italic> and <italic>RpII215</italic> hold potential for developing insect strains that can selectively kill using elevated temperatures; however, alleles with milder effects than <italic>shi<sup>ts1</sup></italic> will need to be considered.</p>