The white gene controls copulation success in Drosophila melanogaster

Chengfeng Xiao,Shuang Qiu,R Meldrum Robertson

doi:10.1038/s41598-017-08155-y

Abstract

Characteristics of male courtship behavior in Drosophila melanogaster have been well-described, but the genetic basis of male-female copulation is largely unknown. Here we show that the white (w) gene, a classical gene for eye color, is associated with copulation success. 82.5% of wild-type Canton-S flies copulated within 60 minutes in circular arenas, whereas few white-eyed mutants mated successfully. The w+ allele exchanged to the X chromosome or duplicated to the Y chromosome in the white-eyed genetic background rescued the defect of copulation success. The w+-associated copulation success was independent of eye color phenotype. Addition of the mini-white (mw+) gene to the white-eyed mutant rescued the defect of copulation success in a manner that was mw+ copy number-dependent. Lastly, male-female sexual experience mimicked the effects of w+/mw+ in improving successful copulation. These data suggest that the w+ gene controls copulation success in Drosophila melanogaster.

Highlights

Mating behavior in wild-type Drosophila consists of a series of courtship rituals and subsequent copulation
There is a clear involvement of w in sexual discrimination[2, 26] and courtship[12, 13] in male flies, but whether w+ determines male-female copulation success is unknown
We show that loss-of- w is associated with a defect of copulation success in a circular arena, that w+-associated copulation success is independent of eye color phenotype, and that addition of mw+ into a null background rescues male-female copulation success in a manner that is mw+ copy number-dependent

Summary

Introduction

Mating behavior in wild-type Drosophila consists of a series of courtship rituals and subsequent copulation. Sturtevant (1915) reported that Morgan’s white-eyed male flies[16] were less successful than wild-type males in mating females[2]. A ratio of copulation success is 0.75 for white-eyed male to 1 for wild-type male[26] Such a sexual discrimination against white-eyed males eventually results in the elimination of mutant allele from a laboratory population[26]. These findings suggest a role for w in mating selection, there is no direct evidence whether w+ determines successful male-female copulation. We further show that homozygous mw+ alleles over-rectify the reduced courtship activities of w1118 males, and that there is a positive correlation between mw+ copies and copulation success in flies with a w1118 genetic background

Methods

Results

Conclusion