RT Journal Article SR Electronic T1 Direct Visualization of Live Zebrafish Glycan via Single-step Metabolic Labeling with Fluorophore-tagged Nucleotide Sugars JF bioRxiv FD Cold Spring Harbor Laboratory SP 548016 DO 10.1101/548016 A1 Hong, Senlian A1 Sahai-Hernandez, Pankaj A1 Gopaldas Chapla, Digantkumar A1 Moremen, Kelley W. A1 Traver, David A1 Wu, Peng YR 2019 UL http://biorxiv.org/content/early/2019/06/20/548016.abstract AB Dynamic turnover of cell-surface glycans is involved in a myriad of biological events, making this process an attractive target for in vivo molecular imaging. Metabolic glycan labeling coupled with ‘bioorthogonal chemistry’ has paved the way for visualizing glycans in living organisms. However, a two-step labeling sequence is required, which is prone to tissue penetration difficulties for the imaging probes. Here, by exploring the substrate promiscuity of endogenous glycosyltransferases, we developed a single-step fluorescent glycan labeling strategy by directly using fluorophore-tagged analogs of the nucleotide sugars. Injecting the fluorophore-tagged sialic acid and fucose into the yolk of zebrafish embryos at the one-cell stage enables systematic imaging of sialylation and fucosylation in live zebrafish embryos at distinct developmental stages. From these studies, we obtained insights into the role of sialylated and fucosylated glycans in zebrafish hematopoiesis.