Antibody-based techniques have emerged as a powerful tool to use in conjunction with mass spectrometry (MS)-based proteomics to fuel research into the role of post-translational modifications (PTMs) in disease. Among the chaos of cellular processes, PTMs are defining elements that shape the complexity, functionality, and diversity of the proteome.
After protein synthesis, PTMs modify the protein’s chemical and structural aspects, profoundly impacting its activity, localization, and interactions. This modulation allows cells to responsively adjust to external stimuli and an evolving environment, overseeing vital survival and functional processes.
PTMs play a pivotal role in cellular functions, influencing disease etiology and progression. For instance, protein phosphorylation can prompt a cascade of cellular reactions. However, malfunctioning PTMs, like the hyperphosphorylation seen in Alzheimer's, can lead to severe health issues. Advanced technologies from the likes of RayBiotech means the potential for groundbreaking therapeutic interventions draws nearer to fruition.
This article highlights the importance of PTMs in disease research, and advancements in the detection methods used to study it. Embracing these evolving methodologies will undoubtedly further understanding and management of various diseases in the future.
Post-translational modifications can alter the 3D structure of proteins
PTMs have surfaced as major players in the etiology and progression of several diseases.
Post-translational modifications (PTMs) refer to the covalent and enzymatic changes a protein experiences post-ribosomal synthesis. These changes involve adding or removing functional groups, cleaving peptide bonds, or forming new bonds between amino acid side chains. Such modifications can cause structural shifts in proteins, influencing their activity – this might activate or suppress enzymatic functions, change protein localization, modify protein interactions, or mark a protein for degradation.
PTMs have surfaced as major players in the etiology and progression of several diseases. While numerous PTMs are recognized, certain modifications, by virtue of their prevalence and implications, have drawn heightened attention from the scientific community. Here, we shine a spotlight on some of these key PTMs and their roles in disease research.
Understanding the world of post-translational modifications (PTMs) requires a suite of sophisticated tools and techniques. The past few decades have seen significant advancements in this domain, with methodologies emerging that can detect and quantify these modifications with remarkable precision.
MS-based proteomics: Mass spectrometry (MS) has firmly established itself as the cornerstone in the study of PTMs. This technique allows for the identification and quantification of proteins and their post-translational modifications in biological samples. Once proteins are extracted from a sample, they are digested into peptides, which are subsequently separated using liquid chromatography. Upon entering the mass spectrometer, these peptides are ionized, and their mass-to-charge ratios are measured, enabling researchers to deduce the peptide's amino acid sequence and any modifications present. In the domain of disease research, MS has unveiled altered protein phosphorylation patterns in cancer cells, providing valuable insights into potential therapeutic targets.
Antibody-based techniques: Antibody-based methods offer complementary and accessible approaches to detect specific PTMs.
Antibody-based methods offer complementary and accessible approaches to detect specific PTMs.
Given the vast dynamic range and complexity of biological samples, directly analyzing them via MS can be challenging. Enrichment techniques are employed to isolate and concentrate specific PTMs, enhancing the detection sensitivity. For example, metal-affinity chromatography can be employed to enrich phosphopeptides, while acetyl-lysine affinity enrichment can capture acetylated peptides.
Often however, a single technique may not be enough to paint a comprehensive picture of the PTM landscape. Combining MS with antibody-based approaches can offer a holistic understanding. For instance, using PTM-specific antibodies to enrich for specific modifications before MS analysis can marry the specificity of antibodies with the depth of MS-based proteomics.
The journey of understanding post-translational modifications (PTMs) has not been without its challenges. While advancements have broadened our understanding, obstacles persist, emphasizing the need for innovative strategies.
Detecting low-abundance modifications remains a hurdle due to many PTMs' transient nature, often overshadowed by the dominance of non-modified proteins. Technical reproducibility, too, is a concern. The nuanced process of PTM analysis, encompassing everything from sample preparation to advanced detection methods, makes consistent results an aspiration. The introduction of PTM-specific antibodies has been pivotal, but their specificity is not foolproof. Cross-reactivity remains an issue, risking data misinterpretations. Finally, the intricate interplay between concurrent PTMs, such as how phosphorylation might influence acetylation, adds another layer of complexity. Decoding this intricate network and gauging its overall influence on protein function is a formidable undertaking.
What’s next for PTM research?
PTMs play a crucial role in protein regulation. They offer cells a rapid adaptability tool, allowing modification of existing proteins instead of time-consuming new protein synthesis. This mechanism adds great complexity and diversity to biology. For context, while the human genome encodes for around 20,000–25,000 genes, PTMs amplify the functionality of these proteins, allowing a single protein to have multiple roles based on its modifications.
There are a number of avenues research into PTM could take in the future: