Researching the Secrets of Protein Expression and Post-translational Modifications


Proteins are the workhorses of the cell, responsible for carrying out essential functions that keep our bodies functioning optimally. To understand the intricacies of protein function, we must explore protein expression and post-translational modifications (PTMs). In this blog post, we explore what protein expression and PTMs are, their significance, and how they impact various biological processes.

Protein Expression: The Basics

Protein expression is the process by which genetic information stored in DNA is used to synthesize proteins. Understandably, it’s a complex and highly regulated process that involves multiple steps. Here’s a brief overview:

  • Transcription: The first step in protein expression is transcription, where a specific segment of DNA is transcribed into messenger RNA (mRNA) by RNA polymerase.
  • mRNA Processing: The newly synthesized mRNA undergoes various modifications, including capping, splicing, and polyadenylation, to become mature and ready for translation.
  • Translation: During translation, the mRNA is a template to synthesize a protein. Ribosomes read the mRNA codons, and tRNA molecules deliver the corresponding amino acids, which are joined together to form a polypeptide chain.
  • Post-translational Modifications: Once the protein is synthesized, it often undergoes further modifications known as post-translational modifications (PTMs), which play a crucial role in its structure and function.

Post-translational Modifications: Adding Complexity to Proteins

PTMs are chemical modifications that occur after a protein is synthesized. They alter a protein’s structure, stability, localization, and activity, thereby diversifying its functions. Some common PTMs include phosphorylation, glycosylation, acetylation, ubiquitination, and more. Here’s a look at a few key PTMs:

  • Phosphorylation: The addition of phosphate groups to specific amino acid residues can activate or deactivate a protein, regulating its function.
  • Glycosylation: The attachment of sugar molecules to proteins can influence their stability, cell surface binding, and signaling properties.
  • Acetylation: Addition of acetyl groups can alter protein stability, protein-protein interactions, and gene expression.
  • Ubiquitination: Ubiquitin molecules are attached to proteins destined for degradation, marking them for proteasomal or lysosomal degradation.
  • Methylation: Addition of methyl groups to specific amino acids affect protein-protein interactions and gene expression.

Significance of Post-translational Modifications

PTMs are essential for the proper functioning of proteins and, by extension, the entire cell. These modifications regulate processes like signal transduction, cell cycle control, DNA repair, and apoptosis. Additionally, PTMs influence protein localization, ensuring that proteins are delivered to the right cellular compartments. As such, PTMs allow for fine-tuning of protein activity, enabling cells to respond to changing environmental conditions.

Protein Expression and PTMs in Research and Biotechnology

Understanding protein expression and PTMs is vital in both research and biotechnology. Researchers use techniques like Western blotting, mass spectrometry, and immunoprecipitation to study PTMs and protein expression levels. These studies provide insights into disease mechanisms, drug development, and therapeutic targeting.

In biotechnology, protein expression systems are harnessed to produce recombinant proteins for various applications, including drug development, vaccines, and industrial processes. By manipulating protein expression and PTMs, scientists design proteins with specific functions, such as increased stability or altered activity.


Protein expression and post-translational modifications are fundamental processes that govern protein function and cellular behavior. They add a layer of complexity to the world of proteins, allowing cells to adapt and respond to their environment. Understanding these processes is crucial for advancing scientific research but also for harnessing the potential of biotechnology in developing innovative solutions. As we continue to explore protein expression and PTMs, we uncover new possibilities for improving human health and well-being.

Does your research involve post-translational modifications? Contact us to discuss how we can help.