Odorant-binding proteins expression patterns in recently diverged species of Anastrepha fruit flies

Emeline Boni Campanini,Felipe Rafael Torres,Carlos Congrains,Reinaldo Alves De Brito

doi:10.1038/s41598-017-02371-2

Emeline Boni Campanini, Felipe Rafael Torres + Show 2 more

Open Access

https://doi.org/10.1038/s41598-017-02371-2

Copy DOI

Journal: Scientific Reports	Publication Date: May 19, 2017
Citations: 17	License type: open-access

Affiliation: Universidade Federal de São Carlos

Abstract

We studied two species of closely related South American fruit flies, Anastrepha fraterculus and Anastrepha obliqua which, despite being able to interbreed, still show some ecological and reproductive differences. Because part of these differences, such as host and mate preferences, may be related to olfactory perception, we focused our investigation on the differential expression of Odorant-binding protein (OBP) gene family, which participate in initial steps of the olfactory signal transduction cascade. We investigated patterns of expression of eight OBP genes by qPCR in male and female head tissues of both species. The expression patterns of these OBPs suggest that some OBP genes are more likely involved with the location of food resources, while others seem to be associated with mate and pheromone perception. Furthermore, the expression patterns obtained at different reproductive stages indicate that OBP expression levels changed significantly after mating in males and females of both species. All eight OBP genes analyzed here showed significant levels of differential expression between A. fraterculus and A. obliqua, suggesting that they may hold important roles in their olfactory perception differences, and consequently, may potentially be involved in their differentiation.

Highlights

Fruit flies of the Anastrepha fraterculus group (Diptera: Tephritidae) are some of the most important fruit pests in South America, and exhibit a limited number of morphological and genetic distinguishing characters[1, 2], possibly because they have diverged recently[3]
We investigated the patterns of expression by quantitative PCR (qPCR) of eight Odorant-binding protein (OBP) genes in male and female heads of A. fraterculus and A. obliqua that showed either evidence of positive selection[26, 27] or were found to have differential expression between these species
Whereas OBP56d and OBP83cd were up-regulated in A. obliqua, OBP56a was up-regulated in A. fraterculus, at a level of differential expression much higher than the other significant gene comparisons here identified (Table 1), which indicate species differences in patterns of expression

Summary

Introduction

Fruit flies of the Anastrepha fraterculus group (Diptera: Tephritidae) are some of the most important fruit pests in South America, and exhibit a limited number of morphological and genetic distinguishing characters[1, 2], possibly because they have diverged recently[3]. We investigated the patterns of expression by qPCR of eight OBP genes in male and female heads of A. fraterculus and A. obliqua that showed either evidence of positive selection[26, 27] or were found to have differential expression between these species We analyzed how these genes are expressed at different reproductive stages in each species, which could suggest whether these OBPs are more probably involved with food or mate location. Since differences in OBP expression patterns may effect different olfactory responses and, elicit important ecological and behavioral consequences, a better understanding of the expression of these genes may bring important information on the diversification and speciation of closely related species such as those from the Anastrepha fraterculus group, which could help develop potential targets for species-specific control of these, and other, pest species

Methods

Results

Conclusion