Rapid metabolic screening of early zebrafish embryogenesis based on direct infusion-nanoESI-FTMS

Single zebrafish eggs were rapidly profiled using high resolution-direct infusion-nanoelectrospray-mass spectrometry with limited sample preparation and without separation. The analysis time per sample is around 1 min. Using this approach the different developmental stages of zebrafish eggs can be characterized by their active metabolites. Five different development stages with distinct metabolic fingerprints could clearly be observed when untargeted analysis is performed and the data are plotted using principal component analysis. Using this approach early embryogenesis is followed with a time resolution of 1 h and 102 features proved relevant. Of these, significant number of putatively identified compounds has not been reported earlier to have any association with early zebrafish embryogenesis yet. The onset of gene expression and the increase in energy requirement is reflected by the measured metabolome complementing earlier reported transcriptomics studies from a systems biology point of view. By deyolking and dechorionation eggs at two early developmental stages, we were able to observe distinct changes in localized metabolism.