Feeding the world sustainably: efficient nitrogen use

Globally, overuse of nitrogen (N) fertilizers in croplands is causing severe environmental pollution. In this context, Gu et al. suggest environmentally friendly and cost-effective N management practices and Hamani et al. highlight the use of microbial inoculants to improve crop yields, while reducing N-associated environmental pollution and N-fertilizer use.     

Viral sponges sequester nucleotide signals to inactivate immunity

Bacteria synthesize specialized nucleotide signals to control anti-phage defense. Two papers – by Huiting et al. and Jenson et al. – now reveal that bacteriophages encode protein ‘sponges’ that sequester cyclic oligonucleotide immune signals and inactivate host antiviral immunity.     

Dual function of the CHS3-CSA1 immune receptor pair

Plant nucleotide-binding leucine-rich repeat (NLR) receptors mediate specific recognition of pathogen effectors to initiate effector-triggered immunity. Recently, studies by Schulze et al., Yang et al., and Gu et al. collectively show that the Arabidopsis (Arabidopsis thaliana) NLR pair CHS3-CSA1 acts through two distinct activation modes to recognize different pathogen effectors, thus revealing the dual function of the CHS3-CSA1 pair in plant disease resistance.     

Protein circuit design using de novo proteins

Protein-based biological circuits enable customized control of cellular functions, and de novo protein design enables circuit functionalities that are not possible by repurposing natural proteins. Here, I highlight recent progress in protein circuit design, including CHOMP, developed by Gao et al., and SPOC, developed by Fink et al.     

pH regulates peptide–receptor perception

Diverse plant small peptides are perceived by their corresponding receptors to mediate local or long-distance intercellular communications in various developmental and adaptive programs; notably, the mechanisms of peptide–receptor perception remain largely unrevealed. Two reports (Liu et al.; Diaz-Ardila et al.) shed light on how pH regulates peptide–receptor perception.     

Pan-genome for pearl millet that beats the heat

A better understanding of crop genomes reveals that structural variations (SVs) are crucial for genetic improvement. A graph-based pan-genome by Yan et al. uncovered 424 085 genomic SVs and provided novel insights into heat tolerance of pearl millet. We discuss how these SVs can fast-track pearl millet breeding under harsh environments.     

Liver-stage Plasmodium infection tunes clinical outcomes

Chora and colleagues show that infection of the liver by Plasmodium modulates severity of disease in the experimental cerebral malaria (ECM) model by generating gamma delta (ɣδ) T cells that produce IL-17. This work calls into question the long-standing assumption that liver infection does not modulate severity of malaria.     

Viral vectors as carriers of genome-editing reagents

The presence of a transgene in the genome of plants is a regulatory challenge. Recently, Liu et al. reported an engineered tomato spotted wilt virus (TSWV) that can carry large clustered regularly interspaced palindromic repeats (CRISPR)/Cas reagents for targeted genome editing in various crops without the integration of the transgene into the genome.     

PASTE: a high-throughput method for large DNA insertions

Prime editing (PE) enables precise genome editing at targeted locus without inducing double-stranded breaks (DSBs). Despite its precision, PE lacks the tendency to integrate large DNA fragments into the genome. Recently, Yarnall et al. reported clustered regularly interspaced palindromic repeats (CRISPR)/Cas9 and an integrase-based system that conducts targeted integration of large DNA sequences (~36 kb) into the genome more efficiently.     

Actin subversion for productive Plasmodium hepatocyte invasion

Productive invasion of hepatocytes by Plasmodium sporozoites is a key step of infection. The parasites traverse hepatocytes before targeting one of them to form a parasitophorous vacuole for parasite expansion. Schepis et al. show the induction of membrane ruffling via host Rho GTPases by Plasmodium sporozoites facilitating productive invasion.     

Small but mighty: microexons in glucose homeostasis

Many molecular mechanisms underlying blood glucose homeostasis remain elusive. Juan-Mateu et al. find that pancreatic islet cells utilize a regulatory program, originally identified in neurons, that involves alternative splicing of microexons in genes important for insulin secretion or diabetes risk.     

Chemical constituents from Valeriana jatamansi

Phytochemical study of Valeriana jatamansi Jones afforded 45 compounds, including twenty-three iridoids (1–23), five sesquiterpenes (24–28), three steroids (29–31) and fourteen lignins (32–45). The structures of these compounds were assigned by detailed interpretation of spectroscopic data (1D and 2D NMR, HRESIMS) and comparisons with the published data. This is the first report of isolation of compounds (1–6, 10, 21, 25, 41, 43, 44, 45) from Valerianaceae, compounds (13, 27, 39) within the genus Valeriana and compound 30 from V. jatamans. The chemotaxonomic data can support the genus Valeriana being accepted as a member of transitional taxa between the family Valerianaceae and Caprifoliaceae.     

Conferring resistance to parasitic witchweed by shifting strigolactone biosynthesis

Strigolactones from the exudates of maize root induce germination of the parasitic witchweed Striga. Recently, Li et al. characterized the biosynthesis pathway of two strigolactones, zealactol and zealactonoic acid, which induce less Striga germination than the major maize strigolactone, zealactone. This study provides a promising strategy for plant protection against parasitic witchweed.     

Endoreplication controls cell size via mechanochemical signaling

During hypocotyl development, an asymmetric auxin gradient causes differential cell elongation, leading to tissue bending and apical hook formation. Recently, Ma et al. identified a molecular pathway that links auxin with endoreplication and cell size through cell wall integrity sensing, cell wall remodeling, and regulation of cell wall stiffness.     

Back to primary endosymbiosis: from plastids to artificial photosynthetic life-forms

Throughout evolution, only two known primary photosynthetic endosymbiosis occurred, which originated the Archaeplastida and the Paulinella spp. Fundamental questions regarding primary endosymbiosis remain unsolved, but may now be addressed with the recent development of chimeric photosynthetic life-form. Cournoyer et al. could establish artificial photosynthetic endosymbiosis between yeast and cyanobacteria.     

Mycoviral gene-incorporating phytopathogenic fungi: a biocontrol agent

Fungal pathogens cause devastating agroeconomic losses. Chemical fungicides are used to control fungal diseases, although this is not an ecofriendly approach. A recent study by Liu et al. highlighted the use of mycoviral gene-incorporating phytopathogenic fungi as biocontrol agents for disease management.     

Spore germination receptors – a new paradigm

David Rudner and his team (Gao et al.) predict a pentameric structure for the GerA alanine-responsive germination receptor of Bacillus subtilis and demonstrate that it behaves as a nutrient-gated ion channel, finally establishing a function for this novel family of receptors and focussing research on early ion movements in germination.     

Naturally engineered plant microbiomes in resource-limited ecosystems

Nature-designed plant microbiomes may offer solutions to improve crop production and ecosystem restoration in less than optimum environments. Through a full exploration of metagenomic data, Camargo et al. showed that a previously unknown microbial diversity enhances nutrient mobilization in stress-adapted plants.