Current mass spectrometry techniques for reading information stored in polymers require one sequencing experiment per sub-sequence, making the process slow. Here, the authors accelerate the reading process by combining tandem mass spectrometry with ion mobility spectrometry.

Dimethyl duplexing of metabolically deuterated water-labeled samples addresses challenges in dynamic proteome studies by enabling direct comparison of label enrichment. Here, the authors demonstrate that this approach allows accurate protein turnover modeling and efficient analysis of liver proteome dynamics in rapamycin-treated versus control mice.

Publication date: Available online 25 November 2025 Source: Journal of Proteomics Author(s): Eva Borràs, Federica Anastasi, Olga Pastor, Marc Suárez-Calvet, Eduard Sabidó

Journal of the American Society for Mass SpectrometryDOI: 10.1021/jasms.5c00322

Journal of the American Society for Mass SpectrometryDOI: 10.1021/jasms.5c00158

Analytical ChemistryDOI: 10.1021/acs.analchem.5c05652

Publication date: Available online 25 November 2025 Source: International Journal of Mass Spectrometry Author(s): Theis I. Solling, Nathan F. Dalleska, Syed S. Hussain, J.L. Beauchamp

Galectin-3 (Gal-3) is a carbohydrate-binding protein which plays crucial roles in inflammation, immune response, cell migration, autophagy, and signaling. At the ocular surface, Gal-3 is also known to crosslink transmembrane mucins across the epithelial cell glycocalyx, forming lattice structures important for barrier function. However, the biological role of Gal-3 in circulating tear fluid remains largely unexplored. Similarly, whether Gal-3 engages extracellular glycoproteins in tears to affect downstream biological processes has yet to be investigated. As increased Gal-3 levels in tears are known to correlate with ocular pathologies such as dry eye disease (DED), we sought to elucidate the Gal-3 interactome in tear fluid and uncover biological insights into the function of Gal-3 beyond adhesion to the epithelial cell surface. Here, we combined ELISA, lectin affinity enrichment, mass spectrometry (MS)-based glycoproteomics, and lectin blotting to uncover Gal-3 interactors and their associated glycoepitopes. Overall, we report nearly 100 proteins enriched from tear fluid across 3 different patients, identifying proteins involved in immune response, inflammation, and antimicrobial activity. Most notably, we report lacritin as a novel ligand for Gal-3 and demonstrate that specific glycoforms of lacritin bearing core 2 O-glycans preferentially engage with Gal-3. Lastly, we show that the Gal-3-lacritin axis is spliceoform-specific and dependent on lacritin multimerization. Taken together, this study elucidates new ligands for Gal-3 in tear film and reveals mRNA splicing and multimerization as new biochemical mechanisms that fine-tune Gal-3 binding events.

Glucocorticoids (GCs) are steroid hormones that bind to glucocorticoid receptor (GR) as ligands to initiate systemic anti-inflammatory effects. GCs are commonly administered alongside chemotherapy to reduce treatment-related side effects in breast cancer patients. However, GC administration has been shown to promote metastasis in breast cancer. In this study, we used quantitative mass spectrometry-based approaches to analyze proteome and phosphoproteome of three breast cancer cell lines following GC treatments. By comparing MCF7, MDA-MB-231, and MDA-MB-436 cells, we suggest that the level of GR significantly affects GC-mediated responses. Additionally, we identify noncanonical transcription factors (TFs) and kinases that are regulated by GCs in different cell lines. Together, our data present GC-induced modulations and modifications at protein level, indicating that breast cancer metastasis occurs via TF- and kinase-dependent signaling pathways. These findings highlight the need for careful consideration of GC use in breast cancer therapy and identify potential molecular targets for mitigating adverse effects.

Passiflora incarnata (Passionflower) has a long history of use in traditional medicine across South America and Europe, primarily for its sedative and hypnotic effects. Recent evidence suggests that its bioactive constituents can modulate cellular signaling pathways. However, its impact on reproductive physiology, particularly sperm motility, remains underexplored. This study aimed to investigate the effects of an aqueous P. incarnata formulation on sperm motility and viability, with the goal of evaluating its potential as a plant-based, non-hormonal contraceptive agent. An aqueous extract of P. incarnata was prepared and subjected to phytochemical analysis to quantify polyphenols, flavonoids, and carbohydrate content using standard assays. Antioxidant activity was assessed via free radical scavenging assays. The presence of bioactive macromolecules was confirmed by liquid chromatography mass spectrometry (LC MS). Goat spermatozoa, isolated from the caudal epididymis, were treated with the formulation. Sperm motility (horizontal and vertical) was evaluated microscopically and spectrophotometrically, respectively. Sperm viability was assessed using standard viability staining. Phytochemical screening revealed high polyphenol (16.85 mg gallic acid equivalent/g) and flavonoid (2.5 mg quercetin equivalent/g) content, along with notable antioxidant activity (87.25%). LC MS confirmed the presence of diverse plant macromolecules. Treatment with the P. incarnata formulation significantly reduced both horizontal (28.5%) and vertical (20%) sperm motility (both p < 0.0001), while sperm viability remained unaffected. The water solubility of the formulation supports its development as a topical contraceptive gel. The aqueous P. incarnata formulation modulates sperm motility without compromising cell viability, likely via biochemical pathway regulation. These findings highlight its potential as a novel, non-hormonal, plant-based contraceptive.

Psoriasis is a chronic skin disease mediated by Th1 and Th17 immune responses and is classified as a systemic inflammatory disorder. Notably, psoriasis is an independent risk factor for myocardial infarction, stroke, and cardiovascular mortality, particularly in severe disease. However, the cellular mechanisms linking psoriasis to cardiovascular disease have not yet been identified. To address this gap, we investigated systemic markers of inflammasome signaling and innate immune activation in patients with psoriasis. Whole blood was collected from 43 patients, including active psoriasis (mild-to-moderate disease) without clinical manifestations of atherosclerosis, inactive psoriasis (minimal disease activity), patients receiving anti-TNF- therapy, and 19 BMI-matched healthy controls. Multiparametric spectral flow cytometry was performed to profile inflammasome signaling, and mass spectrometry-based proteomics was used to obtain unbiased phenotyping of circulating immune cells. Classical monocytes from patients with active psoriasis exhibited heightened NLRP3 protein expression and caspase-1 activity upon brief physiological stimulation, responses absent in inactive psoriasis and healthy controls. Mechanistically, active psoriasis demonstrated elevated plasma ATP and increased monocyte expression of P2X7R, a potent NLRP3 activator. TNF- was identified as a key cytokine, selectively upregulating both P2X7R and NLRP3. Baseline proteomics revealed enriched pathways for monocyte extravasation and cell adhesion, suggesting a pro-thrombotic state. Stimulation increased proteins linked to ROS and mitochondrial stress. Monocytes from active psoriasis exhibited increased baseline activation and, upon stimulation, enhanced monocyte-platelet aggregation, both of which were attenuated by inhibition of mitochondrial ROS. Importantly, anti-TNF therapy normalized ATP levels, P2X7R expression, inflammasome responsiveness, monocyte activation, and monocyte-platelet interactions, supporting the restoration of systemic immune homeostasis. In patients with mild-to-moderate psoriasis, we demonstrate persistent systemic stress, resulting in inflammasome hyperreactivity and increased monocyte-platelet aggregation in response to minor perturbations in cellular homeostasis. Notably, TNF- blockade restores these effects, providing mechanistic insight into how anti-TNF therapy reduces systemic inflammation and cardiovascular risk.

Publication date: Available online 25 November 2025 Source: Talanta Author(s): Ting Guo, Man He, Beibei Chen, Bin Hu

J. Anal. At. Spectrom., 2025, Advance Article DOI: 10.1039/D5JA00268K, PaperWeiwen Huang, Ying Yu, Liang Dong, Xiuqin Deng, Xinyi Zhao, Liwei Liu, Ying Gao A novel method for the highly sensitive detection of trace tellurium (Te) was developed based on photochemical vapor generation (PVG) coupled with inductively coupled plasma mass spectrometry (ICP-MS). To cite this article before page numbers are assigned, use the DOI form of citation above. The content of this RSS Feed (c) The Royal Society of Chemistry

Understanding drug targets and their effects in living cells is challenging. Here, the authors develop SICFA, a label-free proteomics method that sensitively detects drug-induced protein stability changes, thereby identifying targets and downstream pathways directly in living cells.

RNA-protein complexes are critical factors in development, homeostasis, and disease. RNA proteomics methods are essential for characterizing these complexes but suffer from high levels of background, which hinders identification of ribonucleoprotein (RNP) components. Here, we present RNA Antisense Purification followed by Mass Spectrometry 2.0 (RAP-MS 2.0), an updated version our original RAP-MS protocol with innovations in bead preparation, RNA capture, and peptide purification. RAP-MS 2.0 has lower background than our original protocol, and allows lysate to be reused to capture multiple RNAs. We demonstrate that RAP-MS 2.0 recapitulates known RNPs for 7SL, 7SK, RMRP, U1, U2, U6, U7, and Xist. Additionally, we use RAP-MS 2.0 to identify novel RNA-protein interactions between Xist and TREX components and U1 with FET family transcriptional regulators.

Journal of Proteome ResearchDOI: 10.1021/acs.jproteome.5c00296

Publication date: Available online 24 November 2025 Source: Journal of Proteomics Author(s): Isabela de Oliveira Cavalcante Pimentel, Wellington da Silva Santos, Fabio Montoni, Alison Felipe Alencar Chaves, Rosangela Aparecida dos Santos Eichler, Ismael Feitosa Lima, Talita Souza-Siqueira, Milton Yutaka Nishiyama, Lilian de Jesus Oliveira, Emer Suavinho Ferro, Leo Kei Iwai

Journal of the American Society for Mass SpectrometryDOI: 10.1021/jasms.5c00172

Analytical ChemistryDOI: 10.1021/acs.analchem.5c05874

Publication date: Available online 25 November 2025 Source: Journal of Chromatography A Author(s): Muhamad Yahia Kazmouz, Mátyás Mayer, Attila Felinger

This study presents the development of several approaches to obtain, for the first time, proteins and bioactive peptides from grapefruit peels. The experimental conditions of three extraction methodologies based on the use of Ultrasound-Assisted Extraction (UAE) with Tris-HCl buffer, UAE with Natural Deep Eutectic Solvents, and Pressurized Liquid Extraction (PLE) were optimized. Among them, PLE proved to be the most effective approach, yielding a protein-rich extract containing 70% protein. Protein extracts obtained by PLE were submitted to enzymatic hydrolysis with Thermolysin, Alcalase, and Alcalase Pure, and the resulting protein hydrolysates were then evaluated for their antioxidant and antihypertensive activities. Finally, peptides and other molecules present in the protein hydrolysates were identified using ultra-high liquid chromatography coupled to hybrid quadrupole-Orbitrap mass spectrometry. Thus, a total of 75 peptides along with 31 additional compounds mainly classified into the families of flavonoids, carboxylic acids, amino acids, and carbohydrates were identified. Graphical abstract

Publication date: 1 March 2026 Source: Talanta, Volume 299 Author(s): Ludovica Sofia Guadalupi, Cosima Damiana Calvano, Tommaso R.I. Cataldi, Andrea Bernardi, Luca Magazzini, Luciano Tadiello, Valeria Cipolletti, Marco Arimondi

Publication date: Available online 24 November 2025 Source: Analytica Chimica Acta Author(s): Amirsalar Mansouri, Nipun Babu Varukattu, Brennan J. Curole, Omeed Moaven, Jiri Adamec

J. Anal. At. Spectrom., 2026, Accepted Manuscript DOI: 10.1039/D5JA00389J, PaperChaofeng Li, Zhu-Yin Chu, Peng Peng Sn is the main isobaric interference for Cd isotopic compositions determination. To eliminate the Sn, two step separation methods using anion resin combined with commercially available TRU and UTEVA extraction... The content of this RSS Feed (c) The Royal Society of Chemistry

ABSTRACT Rationale Inductively coupled plasma (ICP) is a commonly used ion source for mass spectrometry-based chemical analysis of a wide range of materials. Traditional ICP ion sources use high power (> 1000 W) and significant gas flow (> 10 L/min), rendering them unsuitable for spaceflight, as they are too resource-intensive for planetary spacecraft. Methods To address the technology gap, we designed and developed a laser ablation microwave-induced plasma mass spectrometer (LA-MIP-MS) and experimentally validated the analytical performance of a prototype instrument capable of providing in situ analyses during planetary science missions. We developed a low-pressure plasma ion source and interfaced it to a heritage quadrupole mass spectrometer (QMS) to perform elemental and isotopic analysis of solid samples via laser ablation. The low power plasma ion source was generated at