From Wikipedia, the free encyclopedia
For vocabulary, see Glossary of gene expression terms. For a non-technical introduction to the topic, see Introduction to genetics.
Flow of genetic information.
Genes are expressed by being transcribed into RNA, and this transcript may then be translated into protein.
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as transfer RNA (tRNA) or small nuclear RNA (snRNA) genes, the product is a functional RNA.
The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and utilized by viruses—to generate the macromolecular machinery for life.
Several steps in the gene expression process may be modulated, including the transcription, RNA splicing, translation, and post-translational modification of a protein. Gene regulation gives the cell control over structure and function, and is the basis for cellular differentiation, morphogenesis and the versatility and adaptability of any organism. Also it depends on the state of activator RNA. Gene regulation may also serve as a substrate for evolutionary change, since control of the timing, location, and amount of gene expression can have a profound effect on the functions (actions) of the gene in a cell or in a multicellular organism.
In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, i.e. observable trait. The genetic code stored in DNA is "interpreted" by gene expression, and the properties of the expression give rise to the organism's phenotype. Such phenotypes are often expressed by the synthesis of proteins that control the organism's shape, or that act as enzymes catalysing specific metabolic pathways characterising the organism. Regulation of gene expression is thus critical to an organism's development.
1.2 RNA processing
1.3 Non-coding RNA maturation
1.4 RNA export
1.8 Protein transport
2 Regulation of gene expression
2.1 Transcriptional regulation
2.2 Transcriptional regulation in cancer
2.3 Post-transcriptional regulation
2.4 Three prime untranslated regions and microRNAs
2.5 Translational regulation
2.6 Protein degradation
3.1 mRNA quantification
3.2 RNA Profiles in Wikipedia
3.3 Protein quantification
4 Expression system
4.1 Inducible expression
4.2 In nature
5 Gene networks
6 Techniques and tools
7 See also
9 External links