pFind Studio: a computational solution for mass spectrometry-based proteomics
2024
Angewandte Chemie2024. Zhou, Mengya et al.
State Key Laboratory of Bioactive Molecules and Druggability Assessment, International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), School of Pharmacy, Jinan University, 601 Huangpu Avenue West, 510632 Guangzhou, China
ABSTRACT:
Use: pChem
Journal of the American Chemical Society2024. Yue Liu et al.
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, 601 Huangpu Avenue West, Guangzhou 510632, China
ABSTRACT:
Use: pChem
Communications chemistry2024. Zhao, Yuanyuan et al.
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, 601 Huangpu Avenue West, Guangzhou, 510632, China
ABSTRACT:
Use: pChem; pQuant
Blood2024. Guan, Ai et al.
Department of Hematology, Peking Union Medical College Hospital, Beijing, China
ABSTRACT:
Use: pFind; pGlyco
Experimental Technology and Management2024. Huiling, WANG et al.
School of Chemistry, Central China Normal University, Wuhan 430079, China
ABSTRACT:
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Ecotoxicology and Environmental Safety2024. Cheng, Wanli et al.
National Key Laboratory of Agricultural Microbiology and National Engineering Research Center of Microbial Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
ABSTRACT:
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Cell Death Discovery2024. Dong, Xiaoshu et al.
State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
ABSTRACT:Naturally occurring isothiocyanates (ITCs) found in cruciferous vegetables, such as benzyl isothiocyanate (BITC), phenethyl isothiocyanate (PEITC), and sulforaphane (SFN), have attracted significant research interest for their promising anti-cancer activity in vitro and in vivo. While the induction of apoptosis is recognized to play a key role in the anti-cancer effects of ITCs, the specific protein targets and associated upstream events underlying ITC-induced apoptosis remain unknown. In this study, we present a set of chemical probes that are derived from BITC, PEITC, and SFN and equipped with bioorthogonal alkynyl handles to systematically profile the target proteins of ITCs in live cancer cells. Using a competition-based quantitative chemical proteomics approach, we identify a range of candidate target proteins of ITCs enriched in biological processes such as apoptosis. We show that BID, an apoptosis regulator of the Bcl-2 family, is covalently modified by ITCs on its N-terminal cysteines. Functional characterization demonstrates that covalent binding to N-terminal cysteines of BID by PEITC results in conformational changes of the protein and disruption of the self-inhibitory interaction between N- and C-terminal regions of BID, thus unleashing the highly active C-terminal segment to exert downstream pro-apoptotic effects. Consistently, PEITC promotes the cleavage and mitochondrial translocation of BID, leading to a strong induction of apoptosis. We further show that mutation of N-terminal cysteines impairs the N- and C-terminal interaction of BID, relieving the self-inhibition and enhancing its apoptotic activity. Overall, our chemical proteomics profiling and functional studies not only reveal BID as the principal target of PEITC in mediating upstream events for the induction of apoptosis, but also uncover a novel molecular mechanism involving N-terminal cysteines within the first helix of BID in regulating its pro-apoptotic potential.
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Analytical Chemistry2024. Zhou, Keting et al.
MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing 10084, China
ABSTRACT:Mapping disulfide linkages is crucial for characterizing pharmaceutical proteins during drug development and quality control. Traditional bottom-up protein analysis workflows often suffer from incomplete mapping for tryptic peptides consisting of multiple disulfide bonds. Although the employment of a partial reduction of disulfide bonds can improve disulfide mapping, it becomes a bottleneck of analysis because individual tuning is often needed. Herein, we have developed an online disulfide-ene reaction system in which the composition of the reaction solvent can be programmed to achieve optimal partial reduction of tryptic disulfide peptides after liquid chromatography separation. By coupling this system onto a bottom-up protein analysis workflow, high coverage for sequencing (71-83%) and disulfide mapping (84-100%) was achieved for standard proteins consisting of 4-19 disulfide bonds. The analytical capability was further demonstrated by mapping 13 scrambled disulfide bonds in lysozyme and achieving compositional analysis of IgG isotypes (kappa and lambda) and subclasses (IgG1-IgG4) from human plasma.
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Journal of Biological Chemistry2024. Zhao, Jianxin et al.
Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
ABSTRACT:O-linked N-acetylglucosamine (O-GlcNAc) is the most abundant mono-saccharide modification occurring in the cytoplasm, nucleus, and mitochondria. The recent advent of mass spectrometry technology has enabled the identification of abundant O-GlcNAc transferase (OGT) substrates in diverse biological processes, such as cell cycle progression, replication, and DNA damage response. Herein we report the O-GlcNAcylation of Replication Protein A2 (RPA2), a component of the heterotrimeric RPA complex pivotal for DNA metabolism. We found that RPA2 interacts with OGT, and a topoisomerase II inhibitor, etoposide, diminishes the association. Using higher-energy collisional dissociation mass spectrometry, we mapped RPA2 O-GlcNAc sites to be Ser-4/Ser-8, which are well-known PIKK-dependent RPA2 phosphorylation sites involved in checkpoint activation upon replication stress. We further demonstrated that Ser-4/Ser-8 O-GlcNAcylation antagonizes phosphorylation and impairs downstream Chk1 activation. Moreover, RPA2 O-GlcNAcylation sustains H2AX phosphorylation upon etoposide treatment and promotes inappropriate cell cycle progression, indicative of checkpoint defects. Our work not only unveils a new OGT substrate, but also underscores the distinct roles of OGT in replication versus replication stress.
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Briefings in Bioinformatics2024. Ji, Mingjun et al.
Peking
ABSTRACT:Recent advances in neoantigen research have accelerated the development of immunotherapies for cancers, such as glioblastoma (GBM). Neoantigens resulting from genomic mutations and dysregulated alternative splicing have been studied in GBM. However, these studies have primarily focused on annotated alternatively-spliced transcripts, leaving non-annotated transcripts largely unexplored. Circular ribonucleic acids (circRNAs), abnormally regulated in tumors, are correlated with the presence of non-annotated linear transcripts with exon skipping events. But the extent to which these linear transcripts truly exist and their functions in cancer immunotherapies remain unknown. Here, we found the ubiquitous co-occurrence of circRNA biogenesis and alternative splicing across various tumor types, resulting in large amounts of long-range alternatively-spliced transcripts (LRs). By comparing tumor and healthy tissues, we identified tumor-specific LRs more abundant in GBM than in normal tissues and other tumor types. This may be attributable to the upregulation of the protein quaking in GBM, which is reported to promote circRNA biogenesis. In total, we identified 1057 specific and recurrent LRs in GBM. Through in silico translation prediction and MS-based immunopeptidome analysis, 16 major histocompatibility complex class I-associated peptides were identified as potential immunotherapy targets in GBM. This study revealed long-range alternatively-spliced transcripts specifically upregulated in GBM may serve as recurrent, immunogenic tumor-specific antigens.
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