Question

What is a polysome?

Short answer

A polysome, or polyribosome, is a complex of an mRNA molecule and two or more ribosomes that acts in protein synthesis. Its structure comprises multiple ribosomes along an mRNA molecule. The polysome translates the mRNA into the amino acid sequence of a protein, increasing the speed of protein synthesis.

Step-by-step solution

Definition

A polysome, also known as polyribosome, is a complex of an mRNA molecule and two or more ribosomes that is formed during active translation.

Structure

The structure of a polysome is essentially a string of ribosomes trailing along an mRNA molecule. This mRNA molecule serves as a blueprint for protein synthesis. It contains the information needed to produce a specific protein.

Function and Importance in Protein Synthesis

The function of a polysome is to synthesize proteins based on the transcript (mRNA). With multiple ribosomes, the polysome can quickly translate the mRNA into the amino acid sequence of a protein and thus, greatly increase the speed of protein synthesis. That's why polysomes play an essential role in protein synthesis.