Biology subjects

Rister, J.

Publications and source records attributed to Rister, J..

3 recordsLinked to original sources

bioRxiv2026

Natural genetic variation spans all predicted Rh5/Rh6 expression phenotypes in Drosophila R8 photoreceptors

Standing genetic variation is immediately available to selection, but how broad a range of phenotypes it can produce remains unknown for many traits. Here we address this question using the mutually exclusive Rhodopsin 5 (Rh5) and Rhodopsin 6 (Rh6) expression pattern in Drosophila R8 photoreceptors, a neuronal differentiation readout that permits enumeration of a finite set of predicted qualitative phenotypic changes. Wild flies and wild-derived inbred lines from the Drosophila Genome Reference Panel 2 (DGRP2) showed extensive variation in Rh5/Rh6 expression, including shifts in the relative abundance of Rh5- and Rh6-expressing R8s, Rh5/Rh6 co-expression, and loss of Rh5 or Rh6. Among 205 DGRP2 lines, we observed examples spanning all eight predicted qualitative phenotype categories. We also identified causal coding and regulatory variants, including alleles of sevenless, Rh5 and Rh6, and an intronic deletion in melted. These results show that standing natural variation can span the full predicted range of qualitative phenotypes in this system.

genetics↗

bioRxiv2023

Lipidome unsaturation affects the morphology and proteome of the Drosophila eye.

While the proteome of an organism is largely determined by the genome, the lipidome is shaped by a poorly understood interplay of environmental factors and metabolic processes. To gain insights into the underlying mechanisms, we analyzed the impacts of dietary lipid manipulations on the ocular proteome of Drosophila melanogaster. We manipulated the lipidome with synthetic food media that differed in the supplementation of an equal amount of saturated or polyunsaturated triacylglycerols. This allowed us to generate flies whose eyes had a highly contrasting length and unsaturation of glycerophospholipids, the major lipid class of biological membranes, while the abundance of other membrane lipid classes remained unchanged. By bioinformatically comparing the resulting ocular proteomic trends and contrasting them with the impacts of vitamin A deficiency, we identified ocular proteins whose abundances are differentially affected by lipid saturation and unsaturation. For instance, we unexpectedly identified a group of proteins that have muscle-related functions and increase their abundances in the eye upon lipidome unsaturation but are unaffected by lipidome saturation. Moreover, we identified two differentially lipid-responsive proteins involved in stress responses, Turandot A and Smg5, whose abundances decrease with lipid unsaturation. Lastly, we discovered that the ocular lipid class composition is robust to dietary changes and propose that this may be a general homeostatic feature of the organization of eukaryotic tissues, while the length and unsaturation of fatty acid moieties is more variable to compensate environmental challenges. We anticipate that these insights into the molecular responses of the Drosophila eye proteome to specific lipid manipulations will guide the genetic dissection of the mechanisms that maintain visual function when the eye is exposed to dietary challenges.

neuroscience↗

bioRxiv2023

Eye proteome of Drosophila melanogaster

The Drosophila melanogaster eye is a popular model to elucidate the molecular mechanisms that underlie the structure and function of the eye as well as the causes of retinopathies. For instance, the Drosophila eye has been used to investigate the impacts of ageing and environmental stresses such as light-induced damage or dietary deficiencies. Moreover, large-scale screens have isolated genes whose mutation causes morphological and functional ocular defects, which includes key components of the phototransduction cascade. However, the proteome of the Drosophila eye is poorly characterized. Here, we used GeLC-MS/MS to quantify 3516 proteins he adult Drosophila melanogaster eye and provide a generic and expandable resource for further genetic, pharmacological, and dietary studies.

neuroscience↗