Characterization of the genetic architecture underlying eye size variation within Drosophila melanogaster and Drosophila simulans

DOI: 10.1534/g3.119.400877

Authors: Pedro Gaspar (Howard Hughes Medical Institute) , Saad Arif (Oxford Brookes University) , Lauren Sumner-Rooney (Oxford University Museum of Natural History) , Maike Kittelmann (Oxford Brookes University) , Andrew J. Bodey (Diamond Light Source) , David L. Stern (Howard Hughes Medical Institute) , Maria D. S. Nunes (Oxford Brookes University) , Alistair P. Mcgregor (Oxford Brookes University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: G3 Genes Genomes Genetics

State: Published (Approved)
Published: January 2020
Diamond Proposal Number(s): 23250

Abstract: The compound eyes of insects exhibit striking variation in size, reflecting adaptation to different lifestyles and habitats. However, the genetic and developmental bases of variation in insect eye size is poorly understood, which limits our understanding of how these important morphological differences evolve. To address this, we further explored natural variation in eye size within and between four species of the Drosophila melanogaster species subgroup. We found extensive variation in eye size among these species, and flies with larger eyes generally had a shorter inter-ocular distance and vice versa. We then carried out quantitative trait loci (QTL) mapping of intra-specific variation in eye size and inter-ocular distance in both D. melanogaster and D. simulans. This revealed that different genomic regions underlie variation in eye size and inter-ocular distance in both species, which we corroborated by introgression mapping in D. simulans. This suggests that although there is a trade-off between eye size and inter-ocular distance, variation in these two traits is likely to be caused by different genes and so can be genetically decoupled. Finally, although we detected QTL for intra-specific variation in eye size at similar positions in D. melanogaster and D. simulans, we observed differences in eye fate commitment between strains of these two species. This indicates that different developmental mechanisms and therefore, most likely, different genes contribute to eye size variation in these species. Taken together with the results of previous studies, our findings suggest that the gene regulatory network that specifies eye size has evolved at multiple genetic nodes to give rise to natural variation in this trait within and among species.

Journal Keywords: Drosophila; evolution; development; eye size; ommatidia

Subject Areas: Biology and Bio-materials


Instruments: I13-2-Diamond Manchester Imaging

Added On: 14/01/2020 10:26

Documents:
g3.119.400877.full.pdf

Discipline Tags:

Evolutionary science Genetics Life Sciences & Biotech

Technical Tags:

Imaging Tomography