LTR Retrotransposons as Controlling Elements of Genome Response to Stress?
Transposable elements can impact gene expression and regulatory patterns. This is particularly true for LTR retrotransposons, whose Long Terminal Repeats (LTRs) promoter/regulatory capsules are present at both ends of the element and make them particularly prone to influencing adjacent genes. LTRs can act as promoters, as sources of regulatory sequences, or initiate antisense transcripts regulating gene expression. As a consequence, LTR responses to specific stimuli can influence adjacent host genes and contribute to the organism’s response to these stimuli. Most plant LTR retrotransposons are activated in response to stress or environmental changes, and in this review, we will update current data on this stress response. After a short journey across the animal kingdom, where the regulatory impact of LTRs is well documented, we will present recent reports suggesting that LTRs may also play a role in the modulation of gene expression and in the generation of phenotypic plasticity in plants.
KeywordsRetrotransposon Retroviral LTR Long Terminal Repeat Stress Cotranscrit Expression Host gene
Endogenous Retroviral Element
Long INterspersed Nuclear Element
Long Terminal Repeat
Short INterspersed Nuclear Element
Transcription Start Site
We are very thankful to Prof. Howard Laten for critical reading of the manuscript.
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