Proteome research, also referred to as proteomics research, is the broad study of proteins and their functions. The term “proteome” refers to all of the proteins that are expressed by a given biological unit such as a cell, tissue, or organism. Proteome research aims to accurately discover which proteins are expressed by a given cell, tissue, or organism and to discover each protein's exact purpose and mechanism of action. Proteins are extremely important to all organisms and are involved in almost all of the processes that go on with an organism’s body. They function in processes ranging from metabolism and energy production to cellular signaling and molecule transportation.
Proteins are made up of amino acids. There are twenty-two standard amino acids, and many more non-standard amino acids. There are endless possibilities for combining and modifying the amino acids to form proteins, so the field of proteome research is incredibly complex. Additionally, a cell’s proteome may differ from the proteomes of surrounding cells and tissues, and it may change over time based on various internal or external factors. Complex and deeply involved research methods are therefore necessary to gather information about the protein makeup of an organism.
Antibodies are often used in proteome research because they can be specifically targeted to specific proteins or to specific features on proteins. Researchers, for example, sometimes need to find out if a specific protein is modified in some way, as by the addition of a sugar molecule or some other molecule, after it is initially synthesized. Antibodies can be developed that specifically target these modifications and fluorescent markers or other indicators can be used to show whether or not binding occurs. In some cases, different proteins can even be used to identify modifications on certain proteins of interest. Lectins, or sugar-binding proteins, can be used to determine if glycosylation, the process by which sugar molecules are attached to proteins, has occurred.
Proteome research is generally aimed at discovering and applying protein-based biomarkers to help to diagnose or treat human diseases, such as cancer. A biomarker is a characteristic within the body that can be measured. Biomarkers are useful if they are present at different levels in healthy cells and in pathological cells. Proteome research is aimed at discovering proteins or protein modifications that serve as valuable biomarkers by being expressed at different levels in normal or diseased patients. Some labs, for example, search for different levels of protein glycosylation in the blood of healthy people to compare to the levels found in people with cancer.