@article{morckel_lusic_farzana_yoder_deiters_nascone-yoder_2011, title={A photoactivatable small-molecule inhibitor for light-controlled spatiotemporal regulation of Rho kinase in live embryos}, volume={139}, ISSN={0950-1991 1477-9129}, url={http://dx.doi.org/10.1242/dev.072165}, DOI={10.1242/dev.072165}, abstractNote={To uncover the molecular mechanisms of embryonic development, the ideal loss-of-function strategy would be capable of targeting specific regions of the living embryo with both temporal and spatial precision. To this end, we have developed a novel pharmacological agent that can be light activated to achieve spatiotemporally limited inhibition of Rho kinase activity in vivo. A new photolabile caging group, 6-nitropiperonyloxymethyl (NPOM), was installed on a small-molecule inhibitor of Rho kinase, Rockout, to generate a ‘caged Rockout’ derivative. Complementary biochemical, cellular, molecular and morphogenetic assays in both mammalian cell culture and Xenopus laevis embryos validate that the inhibitory activity of the caged compound is dependent on exposure to light. Conveniently, this unique reagent retains many of the practical advantages of conventional small-molecule inhibitors, including delivery by simple diffusion in the growth medium and concentration-dependent tuneability, but can be locally activated by decaging with standard instrumentation. Application of this novel tool to the spatially heterogeneous problem of embryonic left-right asymmetry revealed a differential requirement for Rho signaling on the left and right sides of the primitive gut tube, yielding new insight into the molecular mechanisms that generate asymmetric organ morphology. As many aromatic/heterocyclic small-molecule inhibitors are amenable to installation of this caging group, our results indicate that photocaging pharmacological inhibitors might be a generalizable technique for engendering convenient loss-of-function reagents with great potential for wide application in developmental biology.}, number={2}, journal={Development}, publisher={The Company of Biologists}, author={Morckel, A. R. and Lusic, H. and Farzana, L. and Yoder, J. A. and Deiters, A. and Nascone-Yoder, N. M.}, year={2011}, month={Dec}, pages={437–442} }
 @article{patel_farzana_robertson_hutchinson_grubbs_shepherd_mahaffey_2007, title={The appendage role of insect disco genes and possible implications on the evolution of the maggot larval form}, volume={309}, ISSN={["0012-1606"]}, DOI={10.1016/j.ydbio.2007.06.017}, abstractNote={Though initially identified as necessary for neural migration, Disconnected and its partially redundant paralog, Disco-related, are required for proper head segment identity during Drosophila embryogenesis. Here, we present evidence that these genes are also required for proper ventral appendage development during development of the adult fly, where they specify medial to distal appendage development. Cells lacking the disco genes cannot contribute to the medial and distal portions of ventral appendages. Further, ectopic disco transforms dorsal appendages toward ventral fates; in wing discs, the medial and distal leg development pathways are activated. Interestingly, this appendage role is conserved in the red flour beetle, Tribolium (where legs develop during embryogenesis), yet in the beetle we found no evidence for a head segmentation role. The lack of an embryonic head specification role in Tribolium could be interpreted as a loss of the head segmentation function in Tribolium or gain of this function during evolution of flies. However, we suggest an alternative explanation. We propose that the disco genes always function as appendage factors, but their appendage nature is masked during Drosophila embryogenesis due to the reduction of limb fields in the maggot style Drosophila larva.}, number={1}, journal={DEVELOPMENTAL BIOLOGY}, author={Patel, Mukund and Farzana, Laila and Robertson, Lisa K. and Hutchinson, Jennifer and Grubbs, Nathaniel and Shepherd, Mark N. and Mahaffey, James W.}, year={2007}, month={Sep}, pages={56–69} }