polysome
Sign in to savethumb|Several ribosomes synthesizing a polypeptide on the same mRNA strand A polysome (or polyribosome or ergosome) is a group of ribosomes bound to an mRNA molecule like "beads" on a "thread". It consists of a complex of an mRNA molecule and two or more ribosomes that act to translate mRNA instructions into polypeptides. Originally coined "ergosomes" in 1963, they were further characterized by Jonathan Warner, Paul M. Knopf, and Alex Rich.
Article
8 sectionsContents
- Structure
- Prokaryotic
- Eukaryotic
- In vitro
- Membrane-bound
- Profiling
- References
- External links
thumb|Several ribosomes synthesizing a polypeptide on the same mRNA strand A polysome (or polyribosome or ergosome) is a group of ribosomes bound to an mRNA molecule like "beads" on a "thread". It consists of a complex of an mRNA molecule and two or more ribosomes that act to translate mRNA instructions into polypeptides. Originally coined "ergosomes" in 1963, they were further characterized by Jonathan Warner, Paul M. Knopf, and Alex Rich.
Polysomes are formed during the elongation phase when ribosomes and elongation factors synthesize the encoded polypeptide. Multiple ribosomes move along the coding region of mRNA, creating a polysome. The ability of multiple ribosomes to function on an mRNA molecule explains the limited abundance of mRNA in the cell. Polyribosome structure differs between prokaryotic polysomes, eukaryotic polysomes, and membrane bound polysomes. Polysome activity can be used to measure the level of gene expression through a technique called polysomal profiling.