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Biology subjects

Lamb, C. H.

Publications and source records attributed to Lamb, C. H..

3 recordsLinked to original sources

Rapid Detection of Active Coronavirus Infection by Lateral Flow Test Strips: A New Approach to Distinguish Replicating Viruses from Non-Replicating Viruses

This manuscript describes the development of an alternative method to detect active coronavirus infection, which targets negative-sense RNA, a product of active viral replication. Few diagnostic methods are capable of discriminating between replicating and non-replicating viruses, complicating decisions related to quarantine and therapeutic interventions. We propose strand-specific nucleic acid diagnostics as a means of distinguishing between active and inactive RNA virus infections and prototype a CRISPR-based lateral flow assay that specifically detects replicating coronaviruses. Such a paradigm in diagnostics could guide more effective public health measures to curb the spread of SARS-CoV-2 and other single-stranded viruses.

microbiology↗

Selective inhibition of protein secretion by abrogating receptor-coat interactions during ER export.

Protein secretion is an essential cellular process that permits cell growth, movement and communication. Traffic of proteins within the eukaryotic secretory pathway is mediated by transport intermediates that bud from one compartment, populated with appropriate cargo proteins, and fuse with a downstream compartment to deliver their contents. Here, we explore the possibility that protein secretion can be selectively inhibited by perturbing protein-protein interactions that drive capture into transport vesicles. Human PCSK9 is a major determinant of cholesterol metabolism, whose secretion is mediated by a specific cargo adaptor of the ER export machinery, SEC24A. We map a series of protein-protein interactions between PCSK9, its ER export receptor, SURF4, and SEC24A, that mediate secretion of PCSK9. We show that the interaction between SURF4 and SEC24A can be inhibited by 4-PBA, a small molecule that occludes a cargo-binding domain of SEC24. This inhibition reduces secretion of PCSK9 and additional SURF4 clients that we identify by mass spectrometry, leaving other secreted cargoes unaffected. We propose that selective small molecule inhibition of cargo recognition by SEC24 is a potential therapeutic intervention for atherosclerosis and other diseases that are modulated by secreted proteins.

cell biology↗

Evidence for nutrient-dependent regulation of the COPII coat by O-GlcNAcylation

O-linked {beta}-N-acetylglucosamine (O-GlcNAc) is a dynamic form of intracellular glycosylation common in animals, plants and other organisms. O-GlcNAcylation is essential in mammalian cells and is dysregulated in myriad human diseases, such as cancer, neurodegeneration and metabolic syndrome. Despite this pathophysiological significance, key aspects of O-GlcNAc signaling remain incompletely understood, including its impact on fundamental cell biological processes. Here, we investigate the role of O-GlcNAcylation in the coat protein II complex (COPII), a system universally conserved in eukaryotes that mediates anterograde vesicle trafficking from the endoplasmic reticulum. We identify new O-GlcNAcylation sites on Sec24C, Sec24D and Sec31A, core components of the COPII system, and provide evidence for potential nutrient-sensitive pathway regulation through site-specific glycosylation. Our work suggests a new connection between metabolism and trafficking through the conduit of COPII protein O-GlcNAcylation.

cell biology↗