proteome

A proteome is the complete set of proteins expressed by an organism. The term can also be used to describe the assortment of proteins produced at a specific time in a particular cell or tissue type. The proteome is an expression of an organism's genome. However, in contrast with the genome, which is characterized by its stability, the proteome actively changes in response to various factors, including the organism's developmental stage and both internal and external conditions.

The study of the proteome is called proteomics, and it involves understanding how proteins function and interact with one another. For instance, many proteins fold into elaborate three-dimensional structures, and some form complexes with each other to perform their functions. In addition, proteins undergo modifications, which may occur either before or after translation. The proteome can be studied using a variety of techniques. For example, two-dimensional gel electrophoresis can be used to separate proteins by their sizes and by their charges. The proteome can also be studied using another laboratory technique called mass spectrometry, which identifies specific proteins within complex samples.