RNA-seq of mondoa zebrafish mutants

The glucose-sensing Mondo pathway regulates expression of metabolic genes in mammals. Here, we have revealed an unexpected role of this pathway in vertebrate embryonic development. We characterized Mondo pathway function in the zebrafish and showed that knock-down of mondoa impaired the early morphogenetic movement of epiboly in zebrafish embryos. Expression of nsdhl , an enzyme of cholesterol and pregnenolone synthesis, was strongly reduced in these embryos. Loss of Nsdhl function likewise impaired epiboly and led to microtubule cytoskeleton defects in the embryo, similar to MondoA loss of function. Both epiboly and microtubule cytoskeleton defects were partially restored by pregnenolone treatment. Gene disruption of mondoa perturbed epiboly with only partial penetrance, likely due to compensatory changes in the expression of cholesterol/steroid metabolism genes. Collectively, our results show a novel role for MondoA in the regulation of early vertebrate development, connecting glucose, cholesterol and steroid hormone metabolism with early embryonic cell movements. RNA-seq in mondoa zebrafish mutants