What is the definition of Proteomics? :
Proteomics is the large-scale study of the complete complement of proteins, specifically their structures, functions, and expression within organelles, cells, tissues, and organisms.
The term Proteome was coined first by Mark Wilkins in 1995. The proteome is a term which describes the entire complement of proteins in a given biological organism, organelle, cell, or system at a certain time or under specific conditions.
The term "proteomics" was coined to coincide with the term "genomics". Although proteomics is the next step in the analysis of the cell, the study of proteins is much more complex than the study of nucleic acids. This is thought to be due to the relatively more complex nature of proteins versus DNA (20 amino acids versus 4 nucleotides for DNA), the myriad modifications such as phosphorylation of proteins, and different forms of the same protein termed splice variants.
Interestingly, although the genome and DNA are rather constant, the proteome differs from cell to cell and is constantly changing through its biochemical interactions with the genome and the environment. One organism has radically different protein expression in different parts of its body, in different stages of its life cycle and in different environmental conditions.