Resources

Proteomics Databases



Metabolomics Databases

• • Top-Down Protein Sequencing: Advantages, Applications, and Challenges

  With the ongoing advancement of proteomics toward higher structural resolution and functional interrogation, the ability to characterize protein structures and post-translational modifications (PTMs) at the intact-protein level has become crucial for elucidating biological functions and disease mechanisms. Top-Down protein sequencing, which directly analyzes intact protein molecules without prior proteolytic digestion, has demonstrated unique advantages across diverse and complex biological systems in......

• • Olink PEA Technology: Principle and Data Analysis Workflow

  In high-plex protein detection, Olink, leveraging its proprietary Proximity Extension Assay (PEA) technology, has become a widely adopted platform for biomarker discovery and population-based cohort studies. The PEA method integrates dual-antibody specific recognition, nucleic acid-based tagging, and highly sensitive signal amplification, enabling high analytical throughput without sacrificing quantitative accuracy. In this report, we provide a systematic overview of the underlying principles of Olink......

• • How Can TurboID-Based Proximity Labeling Enable the Study of Low-Abundance Protein Interactions?

  Low-abundance proteins constitute essential regulators within the cellular protein network, including transcription factors, signaling modulators, and epigenetic regulatory proteins. However, their intrinsically low abundance, spatiotemporally restricted expression, and transient or weak interactions with binding partners make conventional affinity-based approaches such as immunoprecipitation (Co-IP) and pull-down insufficient to recover their genuine interaction networks. The development of proximity......

• • Key Differences Between iTRAQ, TMT, and Label-Free Proteomics

  In modern proteomics research, selecting an appropriate quantification strategy is crucial. With advances in mass spectrometry, iTRAQ (Isobaric Tags for Relative and Absolute Quantitation), TMT (Tandem Mass Tag), and label-free quantification have emerged as three mainstream approaches that are widely applied in studies of disease mechanisms, drug target screening, and clinical biomarker discovery. Although all three approaches rely on high-resolution mass spectrometry platforms, they differ substanti......

• • Tools for PRM Proteomics Data Analysis

  Parallel Reaction Monitoring (PRM) is a targeted protein quantification approach enabled by high-resolution and high-mass-accuracy mass spectrometry platforms. PRM has been extensively applied in cancer biomarker verification, drug target confirmation, and signaling pathway studies. In contrast to Selected Reaction Monitoring (SRM/MRM), PRM utilizes high-resolution instruments such as Orbitrap or Q-TOF systems to acquire full fragment ion spectra, thereby improving analytical selectivity and quantitat......

• • Quantitative Phosphoproteomics with TMT Labeling

  Protein phosphorylation represents one of the most prevalent and functionally important post-translational modifications (PTMs) in eukaryotic cells. It regulates essential biological processes, including cell proliferation, apoptosis, metabolism, and stress responses, and is intimately associated with major human diseases such as cancer, autoimmune disorders, and neurodegenerative diseases. However, phosphorylation events are characterized by dynamic turnover, low abundance, and susceptibility to ion ......

• • What Are the Types of Metabolomics?

  Metabolomics refers to the qualitative and quantitative analysis of all small-molecule metabolites within biological systems, including amino acids, organic acids, sugars, lipids, and other metabolic intermediates. The aim is to elucidate biochemical processes underlying physiological conditions, disease mechanisms, pharmacological responses, or environmental influences based on changes in metabolite abundance. Metabolomics can be classified along multiple dimensions: By research strategy: untargeted......

• • How Do Different Sample Types Affect Exosome Purification Efficiency? (Serum, Plasma, Urine, Saliva)

  Exosomes are nanoscale extracellular vesicles that mediate intercellular communication and hold emerging value in disease biomarker discovery, early cancer screening, and therapeutic delivery. Although exosomes can be isolated from multiple human biofluids, differences in vesicle abundance, biochemical composition, and matrix complexity directly influence purification efficiency and downstream omics data quality. This article compares exosome isolation characteristics across serum, plasma, urine, and ......

• • How to Handle Missing Values in Label-Free Quantitative Proteomics Data?

  In label-free quantitative proteomics, missing values constitute a non-negligible component of downstream data analysis. Missingness is frequently observed within raw mass spectrometry data, and inappropriate handling may compromise statistical inference and lead to biased or misleading biological interpretations. Consequently, rigorous identification and treatment of missing values are critical for ensuring data integrity and analytical reproducibility. Causes and Classification of Missing Values in......

• • What Is the Difference Between Targeted and Untargeted Metabolomics?

  As life science research continues to advance, metabolomics has emerged as an analytical discipline that directly profiles the downstream biochemical outputs of biological processes. Focusing on metabolites enables comprehensive characterization of the dynamic metabolic states of cells, tissues, or biofluids under defined physiological or pathological conditions. Benefiting from progress in high-resolution mass spectrometry, metabolomics has been widely applied in tumor metabolism research, drug metab......