Volume 5 Issue 5, May 2019

A new strategy based on a sophisticated and efficient system of modified pentatricopeptide repeat 10 proteins boost plastid transgene expression and the accumulation of foreign proteins by up to 40-fold.

Comprehensive phylogenomics and molecular dating support a Triassic origin for flowering plants that is substantially earlier than their appearance in the fossil record, leaving a puzzling gap spanning the entire Jurassic period.

Pathogen perception triggers a monomeric nucleotide-binding leucine-rich plant immune receptor to form a pentameric wheel-like complex termed a resistosome, with the N-terminal α helices forming a funnel-shaped structure that may perturb plasma membrane integrity to cause hypersensitive cell death.

A previously unknown biologically active gibberellin present in seeds of Arabidopsis thaliana is formed by hydration of the gibberellin precursor GA₁₂ through the action of GAS2, a 2-oxoglutarate-dependent dioxygenase that decreases sensitivity to abscisic acid and promotes seed germination and seedling establishment.

A study reconstructed angiosperm phylogeny on the basis of plastome data representing 2,351 angiosperm and 187 gymnosperm species, and dated the origin of crown angiosperms to be significantly earlier than the estimates based on fossil data.

Tomato breeding with a desirable MADS-box mutation to improve harvesting can often result in unwanted traits due to negative epistatis with cryptic mutations. A dosage mechanism involving a duplication of a second gene to overcoming the negative epistasis is dissected, enabling the design of gene editing strategies to predictably improve harvesting.

A study using base editing generated transgene-free wheat with mutations that confer resistances to multiple herbicides, and developed a selectable marker that could facilitate co-editing of herbicide resistance and other target traits of interest.

A study reports a regulatory system that boosts transgene expression in the plastids of potato tubers. This system employed an RNA-binding protein PPR10 variant to bind a cognate cis-element of a plastid transgene, encoding GFP, and activate its expression.

Using de novo root regeneration from a detached Arabidopsis leaf as a model system, the authors show that jasmonates are a crucial signalling step from wounding to a local auxin response.

Cotton fibre grows in a protective boll that becomes a barrier for researchers when tracking the growth dynamics. Now, the cytoskeleton in elongating cotton fibres has been visualized by live-cell imaging. The cytoskeleton organization and dynamics shed light on the elongation mode of cotton fibre.

A study used engineered, nuclear-expressed pentatricopeptide repeat proteins with programmable RNA sequence specificity to boost the expression of chloroplast transgenes harbouring cognate cis-elements, providing a method for regulating plastid transgene expression.

FREE1/FYVE1, a component of the ESCRT complex, is essential for the biogenesis of multivesicular bodies. A novel function of this protein is shown here—ABA promotes FREE1 nuclear import to downregulate ABA transcriptional downstream responses.

Retrograde signalling ensures message communication between organelles and the nucleus. A pivotal regulator of plant retrograde signalling, GENOMES UNCOUPLED1, is now found to regulate protein import into chloroplast during chloroplast biogenesis or under stress conditions.

A study uses a forward genetic screen to identify three new regulators (URT1, CPL3 and RST1) for post-transcriptional gene silencing (PTGS). These regulators may suppress PTGS by protecting the 3’ end of transgene transcripts.