Research Briefing in 2023

Here we show that photoexcited blue light receptor cryptochrome 2 (CRY2) mediates blue light-induced liquid–liquid phase separation (LLPS) of CRY2–SPA1–FIO1 trimolecular complexes. This activates the N⁶-methyladenosine (m⁶A) writer FIONA1 (FIO1) to methylate mRNAs that encode chloroplast proteins, which are required for maintaining chlorophyll homeostasis and photosynthesis in response to light.

We reveal that a family of plant stress-induced signalling peptides, SERINE-RICH ENDOGENOUS PEPTIDES (SCOOPs), is much larger than originally thought, and identify key proteases required for their biogenesis. We find that impairing SCOOP biogenesis phenocopies a mutant of the SCOOP receptor MALE DISCOVERER 1-INTERACTING RECEPTOR-LIKE KINASE 2 (MIK2).

Following a catastrophic wildfire, iconic coast redwood (Sequoia sempervirens) trees rebuilt their canopies by leveraging massive, stored carbon reserves, some of which were photosynthesized from the atmosphere 50–100 years ago. New leaves grew from buried buds, which had been dormant for 500–1,000 plus years in the oldest trees.

Genomic polyploidy is prevalent in the plant kingdom, giving rise to dominant and recessive subgenomes. We show that the recessive subgenomes of the pitcher plant Nepenthes gracilis had a crucial role in the acquisition of novel genes with species-specific function such as dioecy and carnivory.

We report the discovery and characterization of two small coiled-coil proteins that belong to the central element of the plant synaptonemal complex.

We report the high-resolution cryo-electron microscopy structures of SOS1, a major determinant of salt tolerance in plants. From our structural and functional analyses, we propose a model for how the unique large cytoplasmic domain regulates the Na⁺/H⁺ exchange activity of SOS1, enhancing our understanding of the mechanisms underpinning the regulation of SOS1 activity.

The plasma membrane Na⁺/H⁺ antiporter SOS1 has a pivotal role in determining salinity tolerance in plants. This study investigates the structure and function of SOS1 from Oryza sativa (rice), elucidating its architecture and activation mechanism, with notable implications for improving crop salt tolerance.

CRISPR-derived base editors can induce guide RNA (gRNA)-independent DNA and RNA off-target edits in eukaryotic cells due to “spurious deamination” by enclosed deaminases. Splitting base editors at a site in a Cas9 nickase-embedded deaminase allows gRNA-mediated base editor reassembly and activation at the target site to suppress unguided off-target edits.

Microscopic visualization of the ARP2/3 complex showed that it colocalizes with peroxisomes in Arabidopsis thaliana and tobacco cells in vivo. Colocalization with an autophagy marker and analysis of peroxisomes in autophagy-mutant or ARP2/3-mutant lines demonstrated that ARP2/3 facilitates peroxisome degradation by the autophagic pathway, that is, pexophagy.

We assessed climatic and productivity trends across the world’s five Mediterranean forest ecosystems and detected large-scale, abrupt forest browning in Chile. Extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are projected to arise in the second half of this century.

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.