Triacylglycerol mobilization underpins mitochondrial stress recovery.

Mitochondria are central to myriad biochemical processes, and thus even their moderate impairment could have drastic cellular consequences if not rectified. Here, to explore cellular strategies for surmounting mitochondrial stress, we conducted a series of chemical and genetic perturbations to Saccharomyces cerevisiae and analysed the cellular responses using deep multiomic mass spectrometry profiling. We discovered that mobilization of lipid droplet triacylglycerol stores was necessary for strains to mount a successful recovery response.

SPE-CZE-MS quantifies zeptomole concentrations of phosphorylated peptides.

Capillary zone electrophoresis (CZE) is gaining attention in the field of single-cell proteomics for its ultra-low-flow and high-resolution separation abilities. Even more sample-limited yet rich in biological information are phosphoproteomics experiments, as the phosphoproteome composes only a fraction of the whole cellular proteome. Rapid analysis, high sensitivity, and maximization of sample utilization are paramount for single-cell analysis.

Identification of a Resistance Exercise-Specific Signaling Pathway that Drives Skeletal Muscle Growth.

A human model of unilateral endurance versus resistance exercise, in conjunction with deep phosphoproteomic analyses, was used to identify exercise mode-specific phosphorylation events. Among the outcomes, a resistance exercise-specific cluster of events was identified, and a multitude of bioinformatic- and literature-based predictions suggested that this was mediated by prolonged activation of a pathway involving MKK3b/6, p38, MK2, and mTORC1. Follow-up studies in humans and mice provide consistent support for the predictions and also revealed that resistance exercise-induced signaling through MKK3b and the induction of protein synthesis are highly correlated events (R = 0.

Regulated N-glycosylation controls chaperone function and receptor trafficking.

One-fifth of human proteins are N-glycosylated in the endoplasmic reticulum (ER) by two oligosaccharyltransferases, OST-A and OST-B. Contrary to the prevailing view of N-glycosylation as a housekeeping function, we identified an ER pathway that modulates the activity of OST-A. Genetic analyses linked OST-A to HSP90B1, an ER chaperone for membrane receptors, and CCDC134, an ER luminal protein.