Reviews & Analysis

Two independently evolved lineages of holoparasites — Balanophora (Santalales) and Sapria (Malpighiales) — display massively convergent characteristics of genome modifications, including gene loss in major pathways, reduction of multigene families and generally relaxed selection pressure. These findings provide valuable new insights into the fascinating biology of parasitic plants.

We identified ZmGLK36, a resistance gene against rice black-streaked dwarf virus (RBSDV), in maize. ZmGLK36 mediates resistance by regulating jasmonic acid (JA) biosynthesis and JA-mediated defence response; it also grants resistance to RBSDV to other cereal crops, such as rice and wheat.

Previous genetic engineering of plant secondary cell walls targeted its core polymers to facilitate their extractability. The ectopic introduction of the polymer callose into poplar wood secondary cell walls modifies the ultrastructure of cellulose microfibril aggregates and suggests new avenues when considering biomass genetic engineering.

We identified the auxin transport-dependent molecular framework that underpins the setting, maintenance and regulation of non-vertical growth patterns in lateral roots of the model plant Arabidopsis thaliana.

Nicotiana benthamiana is a workhorse for fundamental research and biotechnology. We assembled and annotated the allotetraploid chromosomal-level genomes and epigenomes of the laboratory strain and a wild strain of Nicotiana benthamiana, creating a reference genome for the genus Nicotiana.

Plant organ growth relies on intrinsic genetic factors and sufficient supply of nutrients, including metal ions. This work reveals that the transcription factors SOD7 and DPA4 interact with the transcriptional coactivator GIF1 to coordinate plant organ size control and iron uptake by competing with growth and iron uptake regulators.

Using population genomics, we reveal the global dispersal history of eelgrass (Zostera marina) from its origin in the Northwest Pacific Ocean, across to the East Pacific, Atlantic and the Mediterranean Sea. Striking differences in genetic diversity among the locations reflect past glaciations and repeated bottlenecks during Z. marina’s worldwide colonization.

ABACUS2 FRET biosensors allow an unparalleled live view of the dynamics of the plant hormone abscisic acid in plants. Well-watered roots accumulate abscisic acid in growing cells when shoots become dehydrated — a response that is essential to maintain root growth in low-humidity conditions.

Methods for analysing spatial gene expression in plants have been limited in their throughput. Now the imaging method PHYTOMap allows the spatial expression of dozens of genes to be analysed in three-dimensional whole-mount tissue at single-cell resolution, in a transgene-free manner.

Quantitative methods to measure gene transcription in plants typically use large populations of cells and do not maintain spatial information. We developed a method that enables simultaneous quantification of single RNA molecules and protein abundance per cell in intact plant tissues.

Crystal structure-guided exchange of mobile elements from red algal Rubisco into a related bacterial Rubisco enabled us to identify amino acid substitutions that enhance carbon dioxide (CO₂) fixation. In tobacco plants, the improved Rubisco supported a two-fold increase in photosynthetic rates compared with plants producing wild-type bacterial Rubisco.

Epidermal trichomes function as mechanosensors, but how trichome-less plants perceive mechanical forces remains unclear. Touching epidermal pavement cells with micro-cantilevers, we discovered distinct cytosolic calcium waves upon application and release of small forces. Thus, not only do plants perceive forces independently of trichomes, they may also distinguish touch from letting go.

The biosynthesis of plant specialized metabolites is strictly regulated in time and space. We have identified a robust transcriptional network, composed of transcriptional activators, co-activators and repressors, which steers cell-specific and jasmonate-inducible triterpene biosynthesis in the outer tissues of Arabidopsis root tips.

Photorespiration is known to be involved in carbon flux in plants, enabling the carbon lost during RuBisCO oxygenation to be recovered. We show that NPF8.4 is a transporter responsible for sequestering the photorespiratory carbon intermediate glycerate into vacuoles during nitrogen depletion, elucidating a novel function for photorespiration in nitrogen flux.

Maximization of reproductive success is critical for plant fitness. To this end, the flowering process must be finely tuned. We show that the rice florigen-like protein FT-L1 contributes to plant entrance into the reproductive phase and enables a balanced progression of inflorescence development.

A genetic approach that combines forward genetics with dynamically targeted genome-scale CRISPR–Cas9 tools has been developed to unmask phenotypic variation in Arabidopsis thaliana that is otherwise hidden by functional redundancy. This approach, called Multi-Knock, should be readily deployable by scientists and breeders for basic research and to expedite breeding efforts.

Gossypol is a defense compound in cotton; both axially chiral gossypol enantiomers confer pest resistance, but (−)-gossypol is toxic for humans. We identified a gene (GhDIR5) that selectively promotes (−)-gossypol synthesis. GhDIR5 knockout enabled the production of (−)-gossypol-depleted cottonseeds without affecting pest resistance.

Kiwifruit are a dioecious species with genetic sex determination that involves genes in a male-specific region of the Y chromosome. One Y-encoded sex determining gene, Shy Girl, also controls sexually dimorphic traits. This property can explain our observation of recurrent recent changes in these genes’ location in related species.

Plant gene silencing is usually achieved through chromatin modifications and repressive transcription factors. We used a gain-of-function approach in Arabidopsis that identified 14 proteins that can repress gene expression via diverse epigenetic pathways, including DNA methylation, histone modifications and interference with RNA polymerase II transcription.

During evolution, the acquisition of special types of cells and tissues requires new regulatory genes that control cell division and cell differentiation. Here, we found that stomatal basic helix-loop-helix (bHLH) transcription factors are co-opted for the development of seta in the liverwort Marchantia polymorpha, which lacks true stomata.