Potential Benefits of Transposons

Transposons pic

Transposons
Image: broadinstitute.org

Genetics researcher Jef Boeke is a professor in the Department of Biochemistry and Molecular Pharmacology at the NYU Langone Medical Center in New York City. Jef Boeke’s research interests include mobile genetic elements in humans and yeast, often referred to as transposable elements, or “transposons.”

Commonly known as “jumping genes,” transposons are mobile pieces of DNA that can move from one segment of the genome to another. Because transposon insertion can interrupt the expression of important genes, many researchers think of transposons as harmful. However, recent research suggests that transposable elements may play a beneficial role in different types of organisms.

When two strains of bacteria, one with relatively few transposable elements and one with the normal amount, are grown in competitive conditions, the strain with more transposable elements tends to grow more vigorously. Although the exact reasons for this competitive advantage are not yet known, researchers have proposed that transposition facilitates the repair of chromosome breaks. More genetics research needs to be done on the role of transposons at a molecular level.

An Introduction to Transposons

Transposons pic

Transposons
Image: broadinstitute.org

A longtime molecular biology and genetics researcher, Dr. Jef Boeke currently works as a professor and director at the NYU Langone Medical Center in New York City. Throughout his career, Dr. Jef Boeke has conducted a large quantity of research on mobile genetic elements, commonly referred to as transposons.

At the most basic level, a transposon is a sequence of DNA that can “jump” from one section of the genome to another. Jef Boeke’s research focuses on the study of a specific type of transposon called a retrotransposon which “jumps” by producing an RNA molecule as a template for new DNA synthesis, and then copying that RNA with an enzyme called reverse transcriptase to make a new DNA copy, which is then inserted back into the genome. Thus its life cycle can be summarized as DNA > RNA > DNA, similar to the life cycle of retroviruses like human immunodeficiency virus or HIV-1. Retrotransposons make up approximately half of the human genome and up to 90 percent of other genomes in the living world. Many transposon and retrotransposon copies are silent, in that they produce no phenotypic effect as a product of their translocation.

If a transposon lands in the middle of a gene, it can produce a mutation and have a destructive effect. However, transposons may also play a useful role. In addition to producing new combinations of nucleic acid sequences and driving genome evolution, transposons can facilitate the shuffling of exons and help repair damage to the DNA double helix.