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(cell and molecular biology)



(or polysome), a protein-synthesizing complex in living cells; each complex is composed of one molecule of messenger ribonucleic acid (mRNA) and a few or several ribosomes connected to the mRNA molecule.

Polyribosomes are formed by the successive addition of ribosomes to mRNA. As they pass along the mRNA one by one, the ribosomes “read out” the information contained in the mRNA; it means that each ribosome synthesizes one molecule of protein (polypeptide chain) according to the program recorded in the mRNA. Protein synthesis in the cell is effected primarily by polyribosomes rather than by individual ribosomes.

References in periodicals archive ?
Common findings were dilated stacks of rough endoplasmic reticulum, polyribosomes, randomly distributed intermediate filaments, and rare collagen secretion granules (Fig 5).
Contents of DNA, polyribosomes, ribosomal RNA, protein and Chlorophyll.
4]-treated rats suggesting the disruption and disassociation of polyribosomes from endoplasmic reticulum following C[Cl.
He was also the first to demonstrate the relative stability of mammalian (globin) mRNA and its function on polyribosomes in protein synthesis in mammalian cells.
Also, the other cellular alterations such as decreased protein content, increased ribonuclease activity, protein hydrolysis, hydrogen peroxide concentration and dissociation of polyribosomes are also known to occur in plants exposed to water stress [15,22].