Stress does not induce a general transcription of transposable elements in Drosophila

Transposable elements, also known as "jumping genes," have the ability to hop within the host genome. Nonetheless, this capacity is kept in check by the host cell defense systems to avoid unbridled TE mobilization. Different types of stressors can activate TEs in Drosophila, suggesting that TEs may play an adaptive role in the stress response, especially in generating genetic variability for adaptive evolution. TE activation by stressors may also lead to the notion, usually found in the literature, that any form of stress could activate all or the majority of TEs. In this review, we define what stress is. We then present and discuss RNA sequencing results from several studies demonstrating that stress does not trigger TE transcription broadly in Drosophila. An explanation for the LTR order of TEs being the most overexpressed is also proposed.