Real Time Transposable Element Dynamics

Abstract

Transposable elements are mobile genetic elements that are capable of self-catalyzed excision or copying from their host's genome, followed by integration back into another location within the genome. Transposable elements increase in number over time as a result of this activity, and as a consequence can make up a substantial portion of the host's genome as “junk DNA”; both active and dormant transposable elements make up at least 45% of the human genome, and up to 85% of the maize genome. Additionally, the unpredictable reintegration of transposable elements into coding or control regions of the host's genome can have dramatic effects on gene expression, and, as a result of this inherently mutagenic nature, transposable elements are thought to be a major source of genome plasticity driving evolution and are implicated as the direct causative agents of many human diseases, including hemophilia, porphyria, severe combined immunodeficiency, muscular dystrophy, and breast and colon cancers.Despite their ubiquity and potential importance, very little is currently known about the dynamics of transposon propagation through genomes, and their contribution to evolution is inferred from comparative analyses of the genome sequences of related organisms. In this talk I will describe methods developed by my lab employing fluorescent microscopy, microfluidic, and molecular biology techniques to allow the direct visualization of transposable element activity in single cells and in real time. The proposed experimental system is extensible to all types of transposable elements and all cell types, from bacteria to human.