Document Type
Article
Publication Date
4-22-2022
Abstract
Egg size is a fast-evolving trait among Drosophilids expected to change the spatial distribution of morphogens that pattern the embryonic axes. Here we asked whether the patterning of the dorsal region of the embryo by the Decapentaplegic/Bone Morphogenetic Protein-4 (DPP/BMP-4) gradient is scaled among Drosophila species with different egg sizes. This region specifies the extra-embryonic tissue amnioserosa and the ectoderm. We find that the entire dorsal region scales with embryo size, but the gene expression patterns regulated by DPP are not proportional, suggesting that the DPP gradient is differentially scaled during evolution. To further test whether the DPP gradient can scale or not in Drosophila melanogaster, we created embryos with expanded dorsal regions that mimic changes in scale seen in other species and measured the resulting domains of DPP-target genes. We find that the proportions of these domains are not maintained, suggesting that the DPP gradient is unable to scale in the embryo. These and previous findings suggest that the embryonic dorso-ventral patterning lack scaling in the ventral and dorsal sides but is robust in the lateral region where the neuroectoderm is specified and two opposing gradients, Dorsal/NFkappa-B and DPP, intersect. We propose that the lack of scaling of the DPP gradient may contribute to changes in the size of the amnioserosa and the numbers of ectodermal cells with specific cortical tensions, which are expected to generate distinct mechanical forces for gastrulating embryos of different sizes.
Keywords
amnioserosa, dorso-ventral patterning, DPP/BMP-4 gradient, Drosophila species, ectoderm, embryogenesis, evolution of development, gastrulation, gene regulation, scaling of morphogenetic gradients
Language
English
Publication Title
Journal of Experimental Zoology Part B Molecular and Developmental Evolution
Grant
IOS‐1051662
Rights
© 2022 The Authors. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/), which permits non-commercial copying and redistribution of the material in any medium or format, provided the original work is not changed in any way and is properly cited.
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Recommended Citation
Chahda, J. S., Ambrosi, P., & Mizutani, C. M. (2023). The nested embryonic dorsal domains of BMP-target genes are not scaled to size during the evolution of Drosophila species. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, 340, 131–142. https://doi.org/10.1002/jez.b.23137
Manuscript Version
Final Publisher Version