Letters to Nature

Nature 434, 1134-1138 (28 April 2005) | doi:10.1038/nature03509; Received 11 November 2004; Accepted 23 February 2005

Dynamics of Drosophila embryonic patterning network perturbed in space and time using microfluidics

Elena M. Lucchetta1, Ji Hwan Lee1, Lydia A. Fu1, Nipam H. Patel2 & Rustem F. Ismagilov1

  1. Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA
  2. Department of Integrative Biology, Molecular and Cell Biology, and Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California 94720-3140, USA

Correspondence to: Nipam H. Patel2Rustem F. Ismagilov1 Correspondence and requests for materials should be addressed to R.F.I. (Email: r-ismagilov@uchicago.edu) and N.H.P. (Email: nipam@uclink.berkeley.edu).

Biochemical networks are perturbed both by fluctuations in environmental conditions and genetic variation. These perturbations must be compensated for, especially when they occur during embryonic pattern formation. Complex chemical reaction networks displaying spatiotemporal dynamics have been controlled and understood by perturbing their environment in space and time1, 2, 3. Here, we apply this approach using microfluidics to investigate the robust network in Drosophila melanogaster that compensates for variation in the Bicoid morphogen gradient. We show that the compensation system can counteract the effects of extremely unnatural environmental conditions—a temperature step—in which the anterior and posterior halves of the embryo are developing at different temperatures and thus at different rates. Embryonic patterning was normal under this condition, suggesting that a simple reciprocal gradient system is not the mechanism of compensation. Time-specific reversals of the temperature step narrowed down the critical period for compensation to between 65 and 100 min after onset of embryonic development. The microfluidic technology used here may prove useful to future studies, as it allows spatial and temporal regulation of embryonic development.