skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: The genome of the stable fly, Stomoxys calcitrans, reveals potential mechanisms underlying reproduction, host interactions, and novel targets for pest control
Abstract Background The stable fly, Stomoxys calcitrans , is a major blood-feeding pest of livestock that has near worldwide distribution, causing an annual cost of over $2 billion for control and product loss in the USA alone. Control of these flies has been limited to increased sanitary management practices and insecticide application for suppressing larval stages. Few genetic and molecular resources are available to help in developing novel methods for controlling stable flies. Results This study examines stable fly biology by utilizing a combination of high-quality genome sequencing and RNA-Seq analyses targeting multiple developmental stages and tissues. In conjunction, 1600 genes were manually curated to characterize genetic features related to stable fly reproduction, vector host interactions, host-microbe dynamics, and putative targets for control. Most notable was characterization of genes associated with reproduction and identification of expanded gene families with functional associations to vision, chemosensation, immunity, and metabolic detoxification pathways. Conclusions The combined sequencing, assembly, and curation of the male stable fly genome followed by RNA-Seq and downstream analyses provide insights necessary to understand the biology of this important pest. These resources and new data will provide the groundwork for expanding the tools available to control stable fly infestations. The close relationship of Stomoxys to other blood-feeding (horn flies and Glossina ) and non-blood-feeding flies (house flies, medflies, Drosophila ) will facilitate understanding of the evolutionary processes associated with development of blood feeding among the Cyclorrhapha.  more » « less
Award ID(s):
1654417 1950078
PAR ID:
10221623
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Date Published:
Journal Name:
BMC Biology
Volume:
19
Issue:
1
ISSN:
1741-7007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. null (Ed.)
    Abstract Parasites cause harm to their hosts and represent pervasive causal agents of natural selection. Understanding host proximate responses during interactions with parasites can help predict which genes and molecular pathways are targets of this selection. In the current study, we examined transcriptional changes arising from interactions between Drosophila melanogaster and their naturally occurring ectoparasitic mite, Gamasodes queenslandicus . Shifts in host transcript levels associated with behavioural avoidance revealed the involvement of genes underlying nutrient metabolism. These genetic responses were reflected in altered body lipid and glycogen levels in the flies. Mite infestation triggered a striking immune response, while male accessory gland protein transcript levels were simultaneously reduced, suggesting a trade-off between host immune responses to parasite challenge and reproduction. Comparison of transcriptional analyses during mite infestation to those during nematode and parasitoid attack identified host genes similarly expressed in flies during these interactions. Validation of the involvement of specific genes with RNA interference lines revealed candidates that may directly mediate fly–ectoparasite interactions. Our physiological and molecular characterization of the Drosophila – Gamasodes interface reveals new proximate mechanisms underlying host–parasite interactions, specifically host transcriptional shifts associated with behavioural avoidance and infestation. The results identify potential general mechanisms underlying host resistance and evolutionarily relevant trade-offs. 
    more » « less
  2. A major goal in evolutionary biology is to understand how natural variation is maintained in sexually selected and sexually dimorphic traits. Hypotheses to explain genetic variation in sexually selected traits include context-dependent fitness effects, epistatic interactions, and pleiotropic constraints. The house fly, Musca domestica, is a promising system to investigate how these factors affect polymorphism in sexually selected traits. Two common Y chromosomes (YM and IIIM) segregate as stable polymorphisms in natural house fly populations, appear to be locally adapted to different thermal habitats, and differentially affect male mating success. Here, we perform a meta-analysis of RNA-seq data which identifies genes encoding odorant binding proteins (in the Obp56h family) as differentially expressed between the heads of males carrying YM and IIIM Differential expression of Obp56h has been associated with variation in male mating behavior in Drosophila melanogaster. We find differences in male mating behavior between house flies carrying the Y chromosomes that are consistent with the relationship between male mating behavior and expression of Obp56h in D. melanogaster. We also find that male mating behaviors in house fly are affected by temperature, and the same temperature differentials further affect the expression of Obp56h genes. However, we show that temperature-dependent effects cannot explain the maintenance of genetic variation for male mating behavior in house fly. Using a network analysis and allele-specific expression measurements, we find evidence that the house fly IIIM chromosome is a trans regulator of Obp56h gene expression. Moreover, we find that Obp56h disproportionately affects the expression of genes on the D. melanogaster chromosome that is homologous to the house fly IIIM chromosome. This provides evidence for a conserved trans regulatory loop involving Obp56h expression that affects male mating behavior in flies. The complex regulatory architecture controlling Obp56h expression suggests that variation in male mating behavior could be maintained by epistasis or pleiotropic constraints. 
    more » « less
  3. null (Ed.)
    Abstract Background The western flower thrips, Frankliniella occidentalis (Pergande), is a globally invasive pest and plant virus vector on a wide array of food, fiber, and ornamental crops. The underlying genetic mechanisms of the processes governing thrips pest and vector biology, feeding behaviors, ecology, and insecticide resistance are largely unknown. To address this gap, we present the F. occidentalis draft genome assembly and official gene set. Results We report on the first genome sequence for any member of the insect order Thysanoptera. Benchmarking Universal Single-Copy Ortholog (BUSCO) assessments of the genome assembly (size = 415.8 Mb, scaffold N50 = 948.9 kb) revealed a relatively complete and well-annotated assembly in comparison to other insect genomes. The genome is unusually GC-rich (50%) compared to other insect genomes to date. The official gene set (OGS v1.0) contains 16,859 genes, of which ~ 10% were manually verified and corrected by our consortium. We focused on manual annotation, phylogenetic, and expression evidence analyses for gene sets centered on primary themes in the life histories and activities of plant-colonizing insects. Highlights include the following: (1) divergent clades and large expansions in genes associated with environmental sensing (chemosensory receptors) and detoxification (CYP4, CYP6, and CCE enzymes) of substances encountered in agricultural environments; (2) a comprehensive set of salivary gland genes supported by enriched expression; (3) apparent absence of members of the IMD innate immune defense pathway; and (4) developmental- and sex-specific expression analyses of genes associated with progression from larvae to adulthood through neometaboly, a distinct form of maturation differing from either incomplete or complete metamorphosis in the Insecta. Conclusions Analysis of the F. occidentalis genome offers insights into the polyphagous behavior of this insect pest that finds, colonizes, and survives on a widely diverse array of plants. The genomic resources presented here enable a more complete analysis of insect evolution and biology, providing a missing taxon for contemporary insect genomics-based analyses. Our study also offers a genomic benchmark for molecular and evolutionary investigations of other Thysanoptera species. 
    more » « less
  4. The parasitoid wasp Muscidifurax raptorellus (Hymenoptera: Pteromalidae) is a gregarious species that has received extensive attention for its potential in biological pest control against house fly, stable fly, and other filth flies. It has a high reproductive capacity and can be reared easily. However, genome assembly is not available for M. raptorellus or any other species in this genus. Previously, we assembled a complete circular mitochondrial genome with a length of 24,717 bp. Here, we assembled and annotated a high-quality nuclear genome of M. raptorellus , using a combination of long-read (104× genome coverage) and short-read (326× genome coverage) sequencing technologies. The assembled genome size is 314 Mbp in 226 contigs, with a 97.9% BUSCO completeness score and a contig N50 of 4.67 Mb, suggesting excellent continuity of this assembly. Our assembly builds the foundation for comparative and evolutionary genomic analysis in the genus of Muscidifurax and possible future biocontrol applications. 
    more » « less
  5. Abstract Leafhoppers comprise over 20,000 plant‐sap feeding species, many of which are important agricultural pests. Most species rely on two ancestral bacterial symbionts,SulciaandNasuia, for essential nutrition lacking in their phloem and xylem plant sap diets. To understand how pest leafhopper genomes evolve and are shaped by microbial symbioses, we completed a chromosomal‐level assembly of the aster leafhopper's genome (ALF;Macrosteles quadrilineatus). We compared ALF's genome to three other pest leafhoppers,Nephotettix cincticeps,Homalodisca vitripennis, andEmpoasca onukii, which have distinct ecologies and symbiotic relationships. Despite diverging ~155 million years ago, leafhoppers have high levels of chromosomal synteny and gene family conservation. Conserved genes include those involved in plant chemical detoxification, resistance to various insecticides, and defence against environmental stress. Positive selection acting upon these genes further points to ongoing adaptive evolution in response to agricultural environments. In relation to leafhoppers' general dependence on symbionts, species that retain the ancestral symbiont,Sulcia, displayed gene enrichment of metabolic processes in their genomes. Leafhoppers with bothSulciaand its ancient partner,Nasuia, showed genomic enrichment in genes related to microbial population regulation and immune responses. Finally, horizontally transferred genes (HTGs) associated with symbiont support ofSulciaandNasuiaare only observed in leafhoppers that maintain symbionts. In contrast, HTGs involved in non‐symbiotic functions are conserved across all species. The high‐quality ALF genome provides deep insights into how host ecology and symbioses shape genome evolution and a wealth of genetic resources for pest control targets. 
    more » « less