Proximity labeling (PL) has emerged as a powerful technique for the in situ elucidation of biomolecular interaction networks. However, PL methods generally rely on single-biological-hierarchy control of spatial localization at the labeling site, which limits their application in multi-tiered biological systems. Here, we introduced another enzymatic reaction upstream of an enzyme-based PL reaction and targeted the two enzymes to markers indicating different biological hierarchies, establishing a two-level spatially localized proximity labeling (PL) platform for in situ molecular measurement and manipulation.
View Article and Find Full Text PDFCell-cell interactions determine the activation state and function of cells. When host cells are exposed to stressors such as microorganisms, immune defense machinery is activated to release HO, providing direct evidence of the relevant cellular physiological processes. Inspired by the fact that peroxidase can catalyze proximity labeling in the presence of exogenous HO, a stressor-actuated proximity labeling (SAPL) strategy is developed to report the process information on cell-cell interactions by recording stress levels.
View Article and Find Full Text PDFThe difficulty in elucidating the microenvironment of extracellular HO efflux has led to the lack of a critical extracellular link in studies of the mechanisms of redox signaling pathways. Herein, we mounted horseradish peroxidase (HRP) to glycans expressed globally on the living cell surface and constructed an interception proximity labeling (IPL) platform for HO efflux. The release of endogenous HO is used as a "physiological switch" for HRP to enable proximity labeling.
View Article and Find Full Text PDFPrecision remodeling of glycans in their native environments is pivotal for understanding glycan-mediated biological events and has important biotechnological implications in fields of clinical diagnosis, glyco-immune checkpoint therapy, and so forth. However, the influence of aglycone-steric diversity on the selectivity of glycan remodeling has been largely overlooked, limiting the application in complex biological scenarios. Here, we report the achievement of aglycone sterics-selective enzymatic glycan remodeling by controlled grafting of functional polymers from glycoenzyme.
View Article and Find Full Text PDFColorectal cancer (CRC) is the second deadly and the third most common malignancy worldwide. It has been projected that annual new cases of CRC will increase by 63% in 2040, constituting an even greater health challenge for decades to come. This study has linked DEC1 (differentiated embryonic chondrocyte expressed gene 1) to the pathogenesis of CRC.
View Article and Find Full Text PDFglyco-editing on the cell surface can endow cellular glycoforms with new structures and properties; however, the lack of cell specificity and dependence on cells' endogenous functions plague the revelation of cellular glycan recognition properties and hamper the application of glyco-editing in complicated authentic biosystems. Herein, we develop a thermally triggered, cell-specific glyco-editing method for regulation of lectin recognition on target live cells in both single- and cocultured settings. The method relies on the aptamer-mediated anchoring of microgel-encapsulated neuraminidase on target cells and subsequent thermally triggered enzyme release for localized sialic acid (Sia) trimming.
View Article and Find Full Text PDFLipid rafts, highly ordered cell membrane domains mainly composed of cholesterol, sphingolipids, and protein receptors, serve as important functional platforms for regulation of lipid/protein interactions. The major predicament in lipid raft study is the lack of direct and robust visualization tools for in situ tracking raft components. To solve this issue, we herein report a proximity enzymatic glyco-remodeling strategy for direct and highly efficient lipid raft labeling and imaging on live cells.
View Article and Find Full Text PDFGiven the powerful regulation roles of chemical modification networks in protein structures and functions, it is of vital importance to acquire the spatiotemporal chemical modification pattern information in a protein-specific fashion, which is by far a highly challenging task. Herein, we design a localized DNA automaton, equipped with an - sequential propagation algorithm, for visualization of a given protein subtype with two chemical modifications of interest on the cell surface. The automaton is composed of three probes respectively for the protein and two types of modifications.
View Article and Find Full Text PDFThe imaging characterization of spatial proximity of covalently linked structural motifs (e.g., protein-specific glycoform) is essential for thorough understanding of cellular chemistry and biology.
View Article and Find Full Text PDF