@article{1711, keywords = {Animals, Female, Male, Cell Cycle, Models, Biological, Energy Metabolism, Blastula, Deoxyadenine Nucleotides, Metabolome, Metabolomics, Xenopus laevis}, author = {Livia Vastag and Paul Jorgensen and Leonid Peshkin and Ru Wei and Joshua Rabinowitz and Marc Kirschner}, title = {Remodeling of the metabolome during early frog development.}, abstract = {

A rapid series of synchronous cell divisions initiates embryogenesis in many animal species, including the frog Xenopus laevis. After many of these cleavage cycles, the nuclear to cytoplasmic ratio increases sufficiently to somehow cause cell cycles to elongate and become asynchronous at the mid-blastula transition (MBT). We have discovered that an unanticipated remodeling of core metabolic pathways occurs during the cleavage cycles and the MBT in X. laevis, as evidenced by widespread changes in metabolite abundance. While many of the changes in metabolite abundance were consistently observed, it was also evident that different female frogs laid eggs with different levels of at least some metabolites. Metabolite tracing with heavy isotopes demonstrated that alanine is consumed to generate energy for the early embryo. dATP pools were found to decline during the MBT and we have confirmed that maternal pools of dNTPs are functionally exhausted at the onset of the MBT. Our results support an alternative hypothesis that the cell cycle lengthening at the MBT is triggered not by a limiting maternal protein, as is usually proposed, but by a decline in dNTP pools brought about by the exponentially increasing demands of DNA synthesis.

}, year = {2011}, journal = {PLoS One}, volume = {6}, pages = {e16881}, language = {eng}, }