Quantitative system drift compensates for altered maternal inputs to the gap gene network of the Scuttle Fly Megaselia abdita
- Centre for Genomic Regulation, Spain
- Ruprecht Karls University, Germany
- University of Chicago, United States
Abstract
The segmentation gene network in insects can produce equivalent phenotypic outputs despite differences in upstream regulatory inputs between species. We investigate the mechanistic basis of this phenomenon through a systems-level analysis of the gap gene network in the scuttle fly Megaselia abdita (Phoridae). It combines quantification of gene expression at high spatio-temporal resolution with systematic knock-downs by RNA interference (RNAi). Initiation and dynamics of gap gene expression differ markedly between M. abdita and Drosophila melanogaster, while the output of the system converges to equivalent patterns at the end of the blastoderm stage. Although the qualitative structure of the gap gene network is conserved, there are differences in the strength of regulatory interactions between species. We term such network rewiring 'quantitative system drift'. It provides a mechanistic explanation for the developmental hourglass model in the dipteran lineage. Quantitative system drift is likely to be a widespread mechanism for developmental evolution.
Article and author information
Author details
Reviewing Editor
- Naama Barkai, Weizmann Institute of Science, Israel
Version history
- Received: September 16, 2014
- Accepted: January 2, 2015
- Accepted Manuscript published: January 5, 2015 (version 1)
- Version of Record published: February 5, 2015 (version 2)
Copyright
© 2015, Wotton et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Quantitative system drift compensates for altered maternal inputs to the gap gene network of the Scuttle Fly Megaselia abdita
eLife 4:e04785.
https://doi.org/10.7554/eLife.04785
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