uORF-mediated translation allows engineered plant disease resistance without fitness costs

Abstract

Controlling plant disease has been a struggle for mankind since the advent of agriculture. Studies of plant immune mechanisms have led to strategies of engineering resistant crops through ectopic transcription of plants’ own defence genes, such as the master immune regulatory gene NPR11. However, enhanced resistance obtained through such strategies is often associated with significant penalties to fitness2, making the resulting products undesirable for agricultural applications. To remedy this problem, we sought more stringent mechanisms of expressing defence proteins. Based on our latest finding that translation of key immune regulators, such as TBF13, is rapidly and transiently induced upon pathogen challenge (accompanying manuscript), we developed “TBF1-cassette” consisting of not only the immune-inducible promoter but also two pathogen-responsive upstream open reading frames (uORFsTBF1) of the TBF1 gene. We demonstrate that inclusion of the uORFsTBF1-mediated translational control over the production of snc1 (an autoactivated immune receptor) in Arabidopsis (At) and AtNPR1 in rice enables us to engineer broad-spectrum disease resistance without compromising plant fitness in the laboratory or in the field. This broadly applicable new strategy may lead to reduced use of pesticides and lightening of selective pressure for resistant pathogens.

Translational landscape in tomato revealed by transcriptome assembly and ribosome profiling

“…Several studies have illustrated the power of altering mRNA translation via uORFs to improve agriculture (1–3). For example, engineering rice that specifically induces defense proteins when a uORF is repressed by pathogen attack enables immediate plant resistance without compromising plant growth in the absence of pathogens (2). The identification of translated ORFs provides new possibilities to fine-tune the synthesis of proteins involved in diverse physiological pathways.…”

Understanding sheath blight resistance in rice: the road behind and the road ahead

“…Our recent report showed green tissue‐specific expression of master controller AtNPR1 gene in rice enhances ShB resistance avoiding the phenotypic cost (Molla et al , ). Recently, Xu et al () devised another strategy to avert fitness costs due to AtNPR1 expression. The study demonstrated that the translational control of NPR1 gene by the uORFsTBF1 cassette, which comprises of an immune‐inducible promoter and two pathogen‐responsive upstream open reading frames, could engineer plant for disease resistance without compromising fitness penalty.…”

Laccase GhLac1 Modulates Broad-Spectrum Biotic Stress Tolerance via Manipulating Phenylpropanoid Pathway and Jasmonic Acid Synthesis

“…Agrochemical application is the most common method to mitigate biotic stresses in crop plants, but a more sustainable and environmentally friendly strategy is desirable (Xu et al, 2017). A promising approach to reduce such losses is to enhance the immune system of plants through genetic engineering, and this requires an improved understanding of the molecular mechanisms involved (Lacombe et al, 2010).…”