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bioRxiv · 10.1101/2020.10.13.333740

Dimensionality-Reduction in the Drosophila Wing as Revealed by Landmark-Free Measurements of Phenotype

Alba, V.·Carthew, J. E.·Carthew, R. W.·Mani, M.
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Abstract

Organismal development is a complex process, involving a vast number of molecular constituents interacting on multiple spatio-temporal scales in the formation of intricate body structures. Despite this complexity, development is remarkably reproducible and displays tolerance to both genetic and environmental perturbations. This robust-ness implies the existence of hidden simplicities in developmental programs. Here, using the Drosophila wing as a model system, we develop a new quantitative strategy that enables a robust description of biologically salient phenotypic variation. Analyzing natural phenotypic variation across a highly outbred population, and variation generated by weak perturbations in genetic and environmental conditions, we observe a highly constrained set of wing phenotypes. Remarkably, the phenotypic variants can be described by a single integrated mode that corresponds to a non-intuitive combination of structural variations across the wing. This work demonstrates the presence of constraints that funnel environmental inputs and genetic variation into phenotypes stretched along a single axis in morphological space. Our results provide quantitative insights into the nature of robustness in complex forms while yet accommodating the potential for evolutionary variations. Methodologically, we introduce a general strategy for finding such invariances in other developmental contexts.

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Alba, V., Carthew, J. E., Carthew, R. W., Mani, M.. 2020-10-13. Dimensionality-Reduction in the Drosophila Wing as Revealed by Landmark-Free Measurements of Phenotype. https://doi.org/10.1101/2020.10.13.333740

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