skip to main content

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: Evaluation of Additional Drosophila suzukii Male-Only Strains Generated Through Remobilization of an FL19 Transgene
Drosophila suzukii (D. suzukii) (Matsumura, 1931; Diptera: Drosophilidae), also known as spotted wing Drosophila , is a worldwide pest of fruits with soft skins such as blueberries and cherries. Originally from Asia, D. suzukii is now present in the Americas and Europe and has become a significant economic pest. Growers largely rely on insecticides for the control of D. suzukii . Genetic strategies offer a species-specific environmentally friendly way for suppression of D. suzukii populations. We previously developed a transgenic strain of D. suzukii that produced only males on a diet that did not contain tetracycline. The strain carried a single copy of the FL19 construct on chromosome 3. Repeated releases of an excess of FL19 males led to suppression of D. suzukii populations in laboratory cage trials. Females died as a consequence of overexpression of the tetracycline transactivator (tTA) and tTA-activated expression of the head involution defective proapoptotic gene. The aim of this study was to generate additional male-only strains that carried two copies of the FL19 transgene through crossing the original line with a piggyBac jumpstarter strain. Males that carried either two chromosome 3 or a singleX-linked transgene were identified through stronger expression of the red fluorescent protein marker gene. The brighter fluorescence of the X-linked lines was likely due to dosage compensation of the red fluorescent protein gene. In total, four X-linked lines and eleven lines with two copies on chromosome 3 were obtained, of which five were further examined. All but one of the strains produced only males on a diet without tetracycline. When crossed with wild type virgin females, all of the five two copy autosomal strains examined produced only males. However, the single copy X-linked lines did not show dominant female lethality. Five of the autosomal lines were further evaluated for productivity (egg to adult) and male competition. Based on these results, the most promising lines have been selected for future population suppression experiments with strains from different geographical locations.  more » « less
Award ID(s):
2030345
PAR ID:
10389909
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Frontiers in Bioengineering and Biotechnology
Volume:
10
ISSN:
2296-4185
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ( , PLOS Genetics)
    Palli, Subba Reddy (Ed.)
    The transformer ( tra ) gene is essential for female development in many insect species, including the Australian sheep blow fly, Lucilia cuprina . Sex-specific tra RNA splicing is controlled by Sex lethal ( Sxl ) in Drosophila melanogaster but is auto-regulated in L . cuprina . Sxl also represses X chromosome dosage compensation in female D . melanogaster . We have developed conditional Lctra RNAi knockdown strains using the tet-off system. Four strains did not produce females on diet without tetracycline and could potentially be used for genetic control of L . cuprina . In one strain, which showed both maternal and zygotic tTA expression, most XX transformed males died at the pupal stage. RNAseq and qRT-PCR analyses of mid-stage pupae showed increased expression of X-linked genes in XX individuals. These results suggest that Lctra promotes somatic sexual differentiation and inhibits X chromosome dosage compensation in female L . cuprina . However, XX flies homozygous for a loss-of-function Lctra knockin mutation were fully transformed and showed high pupal eclosion. Two of five X-linked genes examined showed a significant increase in mRNA levels in XX males. The stronger phenotype in the RNAi knockdown strain could indicate that maternal Lctra expression may be essential for initiation of dosage compensation suppression in female embryos. 
    more » « less
  2. ; ; ; ( , Archives of Insect Biochemistry and Physiology)
    Abstract

    Spotted wing drosophila,Drosophila suzukii, is an invasive pest that primarily attacks fresh, soft‐skinned fruit. Although others have reported successful integration of markedpiggyBacelements into theD. suzukiigenome, with a very respectable transgenesis rate of ∼16%, here we take this work a step further by creatingD. suzukiijumpstarter strains. These were generated through integration of a fluorescent‐markedMinoselement carrying aheat shock protein 70‐drivenpiggyBac transposasegene. We demonstrate that there is a dramatic increase in transformation rates when germline transformation is performed in atransposase‐expressing background. For example, we achieved transformation rates as high as 80% when microinjectingpiggyBac‐based plasmids into embryos derived from one of theseD. suzukiijumpstarter strains. We also investigate the effect of insert size on transformation efficiency by testing the ability of the most efficient jumpstarter strain to catalyze integration of differently‐sizedpiggyBacelements. Finally, we demonstrate the ability of a jumpstarter strain to remobilize an already‐integratedpiggyBacelement to a new location, demonstrating that our jumpstarter strains could be used in conjunction with apiggyBac‐based donor strain for genome‐wide mutagenesis ofD. suzukii.

     
    more » « less
  3. ; ; ; ; ( , Genes)
    The lack of an annotated reference sequence for the canine Y chromosome has limited evolutionary studies, as well as our understanding of the role of Y-linked sequences in phenotypes with a sex bias. In genome-wide association studies (GWASs), we observed spurious associations with autosomal SNPs when sex was unbalanced in case-control cohorts and hypothesized that a subset of SNPs mapped to autosomes are in fact sex-linked. Using the Illumina 230K CanineHD array in a GWAS for sex, we identified SNPs that amplify in both sexes but possess significant allele frequency differences between males and females. We found 48 SNPs mapping to 14 regions of eight autosomes and the X chromosome that are Y-linked, appearing heterozygous in males and monomorphic in females. Within these 14 regions are eight genes: three autosomal and five X-linked. We investigated the autosomal genes (MITF, PPP2CB, and WNK1) and determined that the SNPs are diverged nucleotides in retrocopies that have transposed to the Y chromosome. MITFY and WNK1Y are expressed and appeared recently in the Canidae lineage, whereas PPP2CBY represents a much older insertion with no evidence of expression in the dog. This work reveals novel canid Y chromosome sequences and provides evidence for gene transposition to the Y from autosomes and the X. 
    more » « less
  4. ; ; ; ; ( , Journal of Pest Science)
    Abstract

    The invasive spotted-wing drosophila,Drosophila suzukii,is a major pest of fruit crops worldwide. Management ofD. suzukiirelies heavily on chemical control in both organic and conventional systems, and there is a need to develop more sustainable management practices. We evaluated the efficacy of three colors of plastic mulches at reducing populations ofD. suzukiiin fall-bearing raspberry and assessed the mulches’ impacts on canopy microclimate factors relevant toD. suzukii. Black, white, and metallic plastic mulches reduced adultD. suzukiipopulations by 42–51% and larval populations by 52–72% compared to the grower standard. The mulches did not change canopy temperature or relative humidity, but metallic mulches increased canopy light intensity compared to the black mulch. Radiance in the visible spectrum (401–680 nm) was higher for the white and metallic mulch plots, but the black mulch plots did not differ from the control. In the UV spectrum (380–400 nm), all three plastic mulches had higher radiance than the control plots. Future studies will determine whether changes in radiance are associated with the observed reduction inD. suzukiipopulations. Plastic mulches are a promising cultural practice for managingD. suzukiisince they can reduce adult and larval populations and could be incorporated into an integrated pest management program in both organic and conventional systems.

     
    more » « less
  5. ; ; ; ( , Journal of Applied Entomology)
    Abstract

    The broad variation in host use among polyphagous insects is well documented but still poorly understood. In numerous pest insects, the proximate mechanisms responsible for variation in oviposition preference among host plants remain to be elucidated. The invasive crop pest,Drosophila suzukii, attacks a wide range of host fruits. Females prefer ovipositing on particular fruit media (blackberry, cherry, blackcurrant) that are rich in phosphorus. As phosphorus is known to be involved in female reproduction in insect species such as Drosophila, it could drive oviposition preference inD. suzukii. Phosphorus is either present as inorganic or organic phosphate in fruits. As the absolute content in macromolecules associated with phosphate in fruits (i.e. proteins and carbohydrates) do not affect oviposition inD. suzukii, we tested for the effect of inorganic phosphate on oviposition preference. We measured the egg‐laying preferences ofD. suzukiiin a choice environment containing 12 artificial media with increasing content in inorganic phosphate (monopotassium dihydrogen phosphate). In our assay,D. suzukiifemales did not prefer ovipositing in media with high inorganic phosphate content compared to media with lower inorganic phosphate content. As a confirmation, we verified the previous result of a higher female preference for media made of phosphorus‐rich fruits (blackberry, cherry, blackcurrant). The higher preference for phosphorus‐rich fruits could be driven by macromolecules containing phosphorus (e.g. phospholipids) or by the presence of one or more molecules that do not contain phosphorus, but that happen to be correlated to fruit phosphorus content. Studying the proximate mechanisms driving host use will ultimately help improve the management ofD. suzukiiand other crop pests.

     
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email