What is the difference between genomes and proteomes

Since DNA is the code, or blueprint, for the construction of cellular proteins , the proteins that an organism can make are limited to those encoded in their genome. The proteome is the full complement of proteins produced by a particular genome.

The genome of an organism is essentially static. It only changes when a mutation occurs. In contrast the proteins being produced by an organism continually change in response to external and internal events. Genes can be 'turned on' and 'turned off', to make proteins only when the cells require them.

In other words, the instructions for making all of an organism's cellular proteins are always there. However, those instructions are not all simultaneously being carried out. For example, beta-lactamase is an enzyme , a molecule made primarily of protein, which penicillin resistant Gram-positive bacteria are able to produce. This enzyme is only produced in the presence of penicillin, and, when produced, it breaks up the penicillin molecule so that it can no longer inhibit bacteria.

Cells are efficient little machines, and are not prone to waste resources when they are not needed. So although the code for beta-lactamase is always present in penicillin-resistant bacteria, it is only produced when needed.

However, the environment also has some influence on the phenotype. DNA in the genome is only one aspect of the complex mechanism that keeps an organism running — so decoding the DNA is one step towards understanding the process. However, by itself, it does not specify everything that happens within the organism. The basic flow of genetic information in a cell is as follows.

The complete set of RNA also known as its transcriptome is subject to some editing cutting and pasting to become messenger-RNA, which carries information to the ribosome, the protein factory of the cell, which then translates the message into protein.

Source: U. This ongoing genomic research in rice is a collaborative effort of several public and private laboratories worldwide. This project aims to completely sequence the entire rice genome 12 rice chromosomes and subsequently apply the knowledge to improve rice production. In , the draft genome sequences of two agriculturally important subspecies of rice, indica and japonica, were published.

Once completed, the rice genome sequence will serve as a model system for other cereal grasses and will assist in identifying important genes in maize, wheat, oats, sorghum, and millet. Proteins are responsible for an endless number of tasks within the cell. The complete set of proteins in a cell can be referred to as its proteome and the study of protein structure and function and what every protein in the cell is doing is known as proteomics.

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.