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Biology subjects

Duffy, E.

Publications and source records attributed to Duffy, E..

2 recordsLinked to original sources

Sexual selection drives the evolution of wing interference patterns.

The seemingly transparent wings of many insects have recently been found to display dramatic structural coloration. These structural colours (wing interference patterns: WIPs) may be involved in species recognition and mate choice, yet little is known about the evolutionary processes that shape them. Additionally, existing research has been restricted by analysing WIPs without due consideration of how they are actually perceived by the viewers colour vision. Here, we use multispectral digital imaging and a model of Drosophila vision to compare WIPs of male and female Drosophila simulans from replicate populations forced to evolve with or without sexual selection for 68 generations. We show for the first time that WIPs modelled in Drosophila vision evolve in response to sexual selection, and confirm that WIPs correlate with male sexual attractiveness. These findings add a new element to the otherwise well described Drosophila courtship display and confirm that wing colours evolve through sexual selection.

evolutionary biology↗

Antisense lncRNA transcription drives stochastic Protocadherin α promoter choice

Stochastic and combinatorial activation of clustered Protocadherin (Pcdh) , {beta}, and {gamma} gene promoters generates a cell-surface identity code in individual neurons that functions in neural circuit assembly. Here we show that Pcdh promoter choice requires transcription of a long noncoding RNA (lncRNA) initiated from newly identified promoters located in the protein coding sequence of each Pcdh exon. Antisense transcription of the lncRNA through the sense promoter results in its activation and in DNA demethylation of the binding sites for the CCCTC-binding protein, CTCF, located in close proximity to both sense and antisense promoters. Increased CTCF binding promotes the assembly of long-range DNA contacts between the activated promoter and a neuron-specific enhancer, thus locking in the epigenetic state of the stochastically chosen Pcdh promoter. Examination of this hierarchical molecular mechanism in differentiating olfactory sensory neurons, suggests that antisense Pcdh transcription is a key prerequisite for stochastic Pcdh promoter choice in vivo.

genomics↗