Chemical genetics of Vertebrate development

Abstract

Small molecules have value in their ability to modulate protein activity in ways that are not accessible using conventional genetic methods, and their potential to be developed into therapeutics. As genetic causes of human disease are identified, many are found to play an integral role in embryonic development as well. The purpose of this dissertation is to utilize vertebrate embryonic development as a platform for discovery and characterization of chemical probes using phenotype guided development. I discovered three molecules, Eggmanone, Incaskin, and Ogremorphin based on ability to perturb development of a composite of 29 anatomical features. Using these anatomical features as a query against the wealth of reference genotype-phenotype data in ZFIN, I identified the targets of the small molecules as PDE4, CK2α, and GPR68. Using eggmanone, I characterize a novel role for PDE4 in regulation of HH signaling, and show that it could be a useful therapeutic target for smo inhibitor resistant cancers. Using incaskin, I show an unbiased phenotypic clustering methodology for target deconvolution; furthermore, I show that incaskin is a highly selective, potent CK2α inhibitor which provides a therapeutic approach for targeting cancers down stream of APC in Wnt signaling. Using ogremorphin, a first in class inhibitor of GPR68, I show that proton sensing GPR68 is critical neural crest migration. Furthermore, I show that proton-sensing GPR68 represents a novel chemically tractably therapeutic avenue for development of an anti-metastatic agent. This body of work contributes to novel discovery of small molecules, signaling, and developmental biology