Monitoring and Identifying Insulin-Like Growth Factor 1 Variants by Liquid Chromatography-High-Resolution Mass Spectrometry in a Clinical Laboratory.

Protein and peptide hormones often exist as sequence variants with different molecular mass. Monitoring these variants of different molecular mass by mass spectrometry using mass-to-charge (m/z) ratio that is indicative of the wild type may lead to inaccurate quantitative results. However, liquid chromatography-high-resolution mass spectrometry (LC-HRMS)-based techniques can capture these differences and provide an opportunity to resolve, or partially resolve, variant complexity.

Isotopic Peak Index, Relative Retention Time, and Tandem MS for Automated High Throughput IGF-1 Variants Identification in a Clinical Laboratory.

Measuring insulin-like growth factor-1 (IGF-1) is useful for assessing and managing growth-related disorders, such as acromegaly and growth hormone deficiency. High-resolution liquid chromatography-mass spectrometry (LC-MS) is used for measuring IGF-1 due to its molecular specificity, quantitative performance, well-characterized reference materials, and detailed age/sex-specific reference intervals. However, polymorphisms in the gene may cause mass shifts in the polypeptide, which can impede quantitation and cause errors in clinical interpretation.

MaXLinker: Proteome-wide Cross-link Identifications with High Specificity and Sensitivity.

Protein-protein interactions play a vital role in nearly all cellular functions. Hence, understanding their interaction patterns and three-dimensional structural conformations can provide crucial insights about various biological processes and underlying molecular mechanisms for many disease phenotypes. Cross-linking mass spectrometry (XL-MS) has the unique capability to detect protein-protein interactions at a large scale along with spatial constraints between interaction partners.

Integrated proteomic and metabolomic analysis suggests high rates of glycolysis are likely required to support high carotenoid accumulation in banana pulp.

To gain a better understanding concerning factors underlying carotenoid metabolism in banana pulp we investigated the carotenoid profile, metabolome, proteome and relative expression levels of carotegenesis-associated genes of fruit pulp in the two banana varieties ON and GN, with ON being characterized of high carotenoid accumulation. Results showed that high carotenoid content in banana pulp was well correlated with the relative expression of carotenogenesis-associated genes and the abundance of the corresponding proteins. An elevated accumulation of sugar metabolism-related compounds and a decreased amino acid accumulation were also observed in ON.

IRE1α-XBP1 controls T cell function in ovarian cancer by regulating mitochondrial activity.

Tumours evade immune control by creating hostile microenvironments that perturb T cell metabolism and effector function. However, it remains unclear how intra-tumoral T cells integrate and interpret metabolic stress signals. Here we report that ovarian cancer-an aggressive malignancy that is refractory to standard treatments and current immunotherapies-induces endoplasmic reticulum stress and activates the IRE1α-XBP1 arm of the unfolded protein response in T cells to control their mitochondrial respiration and anti-tumour function.

Proteome-driven elucidation of adaptive responses to combined vitamin E and C deficiency in zebrafish.

The purpose of this study was to determine the system-wide consequences of deficiencies in two essential micronutrients, vitamins E and C, on the proteome using zebrafish (Danio rerio) as one of the few vertebrate models that similar to humans cannot synthesize vitamin C. We describe a label-free proteomics workflow to detect changes in protein abundance estimates dependent on vitamin regimes. We used ion-mobility-enhanced data-independent tandem mass spectrometry to determine differential regulation of proteins in response to low dietary levels of vitamin C with or without vitamin E.