Cell surface glycans form a critical interface with the biological milieu, informing diverse processes from the inflammatory cascade to cellular migration. Assembly of discrete carbohydrate structures requires the coordinated activity of a repertoire of proteins, including glycosyltransferases and glycosidases. Little is known about the regulatory networks controlling this complex biosynthetic process. Recent work points to a role for microRNA (miRNA) in the regulation of specific glycan biosynthetic enzymes. Herein we take a unique systems-based approach to identify connections between miRNA and the glycome. By using our glycomic analysis platform, lectin microarrays, we identify glycosylation signatures in the NCI-60 cell panel that point to the glycome as a direct output of genomic information flow. Integrating our glycomic dataset with miRNA data, we map miRNA regulators onto genes in glycan biosynthetic pathways (glycogenes) that generate the observed glycan structures. We validate three of these predicted miRNA/glycogene regulatory networks: high mannose, fucose, and terminal β-GalNAc, identifying miRNA regulation that would not have been observed by traditional bioinformatic methods. Overall, our work reveals critical nodes in the global glycosylation network accessible to miRNA regulation, providing a bridge between miRNA-mediated control of cell phenotype and the glycome.glycan regulation | carbohydrate biosynthesis | systems biology | epigenetics | NCI-60

SignificanceCarbohydrates hold an unprecedented capacity for altering biological function, but determining which glycans and underlying enzymes are crucial for a specific biological pathway is a major impediment to our understanding of this posttranslational modification. Here we demonstrate that the mRNA target networks of microRNA (miRNA), small noncoding RNA, identify glycosylation enzymes acting as regulatory elements within a biological pathway. Leveraging the miRNA-200 family (miR-200f), regulators of epithelial-to-mesenchymal transition (EMT), we identify multiple promesenchymal glycosylation enzymes. Silencing miR-200f–targeted glycogenes phenocopies the effect of miR-200f, inducing mesenchymal-to-epithelial transition. These enzymes are upregulated in TGF-β–induced EMT, suggesting tight integration within the signaling network. Our work indicates that miRNA networks can be used to identify crucial glycosylation enzymes driving disease states.