Mechanism of Targeted Proteomics

The core of targeted proteomics lies in the selective detection of specific proteins. Unlike global proteomics, targeted proteomics focuses only on known target proteins, typically based on prior biological research or clinical data. This approach often combines high-throughput mass spectrometry (MS) with specific antibodies, forming a "mass spectrometry-antibody" detection strategy.

 

Steps

1. Sample Preparation

Researchers need to extract proteins from biological samples using methods such as cell lysis, precipitation, and ultrafiltration. Extracted proteins must be separated and concentrated to enhance the analysis sensitivity.

 

2. Selecting Target Proteins

Target proteins are chosen based on their significance in specific biological processes and their relevance in diseases. This is usually accomplished through literature reviews, bioinformatics analyses, or preliminary screening experiments.

 

3. Mass Spectrometry Analysis

In mass spectrometry analysis, proteins are digested into peptides, which are then ionized and introduced into the mass spectrometer for separation and detection. Typically employs multiple reaction monitoring (MRM) or selected reaction monitoring (SRM) modes, allowing for more precise quantification of specific peptides.

 

4. Data Analysis

Analysis software converts the generated mass spectrometry data into quantitative information, and researchers must conduct statistical analyses to determine the expression levels and differences of target proteins across various samples.

 

Mechanisms

1. Sensitivity and Specificity

Targeted proteomics can selectively detect low-abundance target proteins in complex biological samples. This is achieved through the combination of specific antibodies and the high sensitivity of mass spectrometry. Specific antibodies effectively capture target proteins, reducing interference from nonspecific signals, while mass spectrometry provides accurate molecular weight information, enhancing the precision of protein quantification.

 

2. Identification of Biomarkers

Biomarkers play a crucial role in the early diagnosis and prognosis of diseases. By comparing proteomic data from healthy populations and disease patients, researchers can identify target proteins associated with diseases, offering potential for early detection and personalized treatment.

 

3. Studying Drug Mechanisms

By comparing protein expression profiles before and after drug treatment, researchers can identify target proteins affected by the drug and their downstream signaling pathways. This provides important insights for the development and optimization of new drugs.

 

4. Integration and Development of Technologies

Targeted proteomics can also be integrated with other technologies, such as transcriptomics and metabolomics, to achieve comprehensive multi-omics analysis. This integration allows for a more holistic understanding of biological phenomena and their regulatory mechanisms. For instance, combining targeted proteomics with metabolomics can reveal metabolic changes in cells under different environments and their corresponding protein expression changes.

 

As an emerging analytical method, targeted proteomics offers new perspectives for biomedical research through its high sensitivity and specificity. By deeply understanding its mechanisms, researchers can more effectively conduct disease mechanism studies and drug development, contributing to the advancement of precision medicine.