Transposons

Definition

Transposons, also known as jumping genes, are DNA sequences that can change their position within the genome. They play a significant role in genetic diversity and evolution by causing mutations and altering the cell's genetic identity.

5 Must Know Facts For Your Next Test

1. Transposons were discovered by Barbara McClintock in maize and earned her the Nobel Prize in Physiology or Medicine in 1983.
2. There are two main types of transposons: Class I (retrotransposons) and Class II (DNA transposons).
3. Retrotransposons use an RNA intermediate to move, while DNA transposons cut and paste themselves directly from one location to another.
4. Transposons can contribute to antibiotic resistance by transferring genes between different bacterial species.
5. In prokaryotes, transposons can disrupt essential genes or regulatory regions, leading to diverse phenotypic changes.

Review Questions

• Who discovered transposons and what was the significance of this discovery?
• What are the two main types of transposons and how do they differ in their mechanisms of movement?
• How do transposons contribute to antibiotic resistance in bacteria?

Related terms

Mutations: Changes in the DNA sequence that can be caused by various factors including transposon activity.

Plasmids: Small circular DNA molecules found in bacteria that can carry antibiotic resistance genes.

Horizontal Gene Transfer: The movement of genetic material between organisms other than through vertical transmission (parent to offspring).