Volume 9 Issue 11, November 2023

In angiosperms, the proliferation and differentiation of egg and central cells need to be repressed before fertilization. Autonomous endosperm development has been observed and well-studied in Arabidopsis mutants of FERTILIZATION INDEPENDENT SEED (FIS)-class POLYCOMB REPRESSIVE COMPLEX 2 (PRC2), but how defects of PRC2 components affect embryo development remains unclear. Wu et al. now describe an essential clue for understanding parthenogenetic embryogenesis from the rice double mutant osfie1 osfie2.

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.

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 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.

Integrating inventory data with machine learning models reveals the global composition of tree types—needle-leaved evergreen individuals dominate, followed by broadleaved evergreen and deciduous trees—and climate change risks.

Large-scale and abrupt forest decline occurred in Central Chile in response to acute drought. The extreme conditions, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected for the second half of the century.

By editing the mitochondrial genome and screening a large number of deletion mutants, this study shows that clean knockout mutants for a mitochondrial gene can be obtained and used to construct a synthetic cytoplasmic male sterility system.

The deaminases of base editors alone can induce unpredictable off-target edits. This paper describes a simple and generalizable solution for base editors containing distinct deaminases to suppress off-target edits in plant, yeast and human cells.

Wu et al. show that mutations of the Polycomb repressive complex 2 gene, OsFIE2, result in asexual embryo formation in rice, suggesting a critical role of the epigenetic regulation in maintaining the quiescent state of the egg apparatus.

Pre-zygotic reproductive barriers are a vital defence against interspecific pollen transfers in plants. This study shows that SPRI2/SRS7, a transcription factor, regulates the formation of interspecific reproductive barriers in Arabidopsis.

Martinek et al. found that the ARP2/3 complex forms spot-like structures on peroxisomes where it colocalizes and interacts with autophagosomes. Other experiments suggest that ARP2/3 is involved in pexophagy in plant cells.

This study reveals differential roles of conserved oligomeric Golgi subunits in governing Golgi integrity, particularly in prompting accelerated energy-scarcity-induced senescence and establishing a link between Golgi integrity and the cellular ageing processes.

This study reveals the role played by the RNR10-DNR1-auxin module in modulating rice root system architecture and nitrogen uptake, making it a promising target for enhancing nitrogen-use efficiency and grain yield for future sustainable agriculture.

The plasma membrane Na⁺/H⁺ exchanger SOS1 is crucial for plant salt tolerance. Here the authors report the structure of SOS1 from Arabidopsis thaliana in two conformations, which provide structural and functional insight into SOS1 activity regulation.

The cryo-EM structures of SOS1 in the auto-inhibited and activated states reveal that SOS1 undergoes an inhibition–release process upon activation and uses an elevator transport mechanism for Na⁺/H⁺ exchange in response to salt stress.