Biology subjects

Primo, P.

Publications and source records attributed to Primo, P..

3 recordsLinked to original sources

bioRxiv2021

Aedes albopictus bionomics in Procida Island, a promising Mediterranean site for the assessment of innovative and community-based integrated pest management methods.

The colonization of Mediterranean Europe and of other temperate regions by Aedes albopictus created in the last decades an unprecedented nuisance problem in highly infested areas, as well as a new public health threat due to the species competence to transmit exotic arboviruses, such as dengue, chikungunya and zika. The Sterile Insect Technique (SIT) and the Incompatible Insect Technique (IIT) are insecticide-free mosquito-control methods relying on mass release of irradiated/manipulated males which are believed to have a potential in complementing existing and only partially effective control tools. Testing and implementing these approaches are challenging and selection of study sites is an instrumental and crucial step. We carried out a 4-year study in Procida Island (Gulf of Naples, Italy) in strict collaboration with local administrators and citizens to estimate: i) the temporal dynamics, spatial distribution, and population size of Ae. albopictus; and ii) the dispersal and survival of irradiated males. Overall, results provide insights on the bionomics of the mosquito in Southern Europe and draw attention to Procida Island as an ideal site to test innovative control programs against Ae. albopictus which may be used in other Mediterranean and temperate areas."

ecology↗

bioRxiv2019

Maleness-on-the-Y (MoY) orchestrates male sex determination in major agricultural fruit fly pests

In insects, rapidly evolving primary sex-determining signals are transduced by a conserved regulatory module producing sex-specific proteins that direct sex determination and sexual differentiation1-4. In the agricultural pest Ceratitis capitata (medfly), a Y-linked maleness factor (M) is thought to repress the autoregulatory splicing of transformer (Cctra), which is required in XX individuals to establish and maintain female sex determination5,6. Despite previous attempts of isolating Y-linked genes using the medfly whole genome, the M factor has remained elusive7. Here, we report the identification of a Y-linked gene, Maleness-on the-Y (MoY), and show that it encodes a small novel protein which is both necessary and sufficient for medfly male sex determination. Transient silencing of MoY in XY individuals leads to the development of fertile females while transient expression of MoY in XX individuals results in fertile males. Notably, a cross between these sex reverted individuals gives rise to both fertile males and females indicating that a functional MoY can be maternally transmitted. In contrast to the diversity of M factors found in dipteran species8-11, we discovered MoY orthologues in seven other Tephritid species spanning [~]111 millions of years of evolution (Mya). We confirmed their male determining function in the olive fly (Bactrocera oleae) and the oriental fruit fly (Bactrocera dorsalis). This unexpected conservation of the primary MoY signal in a large number of important agricultural pests12 will facilitate the development of transferable genetic control strategies in these species, for example sterile male releases or sex-ratio-distorting gene drives.

genetics↗

bioRxiv2017

Highly efficient DNA-free gene disruption in the agricultural pest Ceratitis capitata by CRISPR-Cas9 RNPs

The Mediterranean fruitfly Ceratitis capitata (medfly) is an invasive agricultural pest of high economical impact and has become an emerging model for developing new genetic control strategies as alternative to insecticides. Here, we report the successful adaptation of CRISPR-Cas9-based gene disruption in the medfly by injecting in vitro pre-assembled, solubilized Cas9 ribonucleoprotein complexes (RNPs) loaded with gene-specific sgRNAs into early embryos. When targeting the eye pigmentation gene white eye (we), we observed a high rate of somatic mosaicism in surviving G0 adults. Germline transmission of mutated we alleles by G0 animals was on average above 70%, with individual cases achieving a transmission rate of nearly 100%. We further recovered large deletions in the we gene when two sites were simultaneously targeted by two sgRNAs. CRISPR-Cas9 targeting of the Ceratitis ortholog of the Drosophila segmentation paired gene (Ccprd) caused segmental malformations in late embryos and in hatched larvae. Mutant phenotypes correlate with repair by non-homologous end joining (NHEJ) lesions in the two targeted genes. This simple and highly effective Cas9 RNP-based gene editing to introduce mutations in Ceratitis capitata will significantly advance the design and development of new effective strategies for pest control management.

genetics↗