Volume 10 Issue 1, January 2024

Currently, hunger affects nearly 12 per cent of the world’s population — 4 per cent more than in 2015, when the United Nations launched the 2030 Agenda for Sustainable Development. If all scientific knowledge and technological innovation in crop development were readily available and globally adopted, could zero hunger have been achieved by 2030? Most people recognize the potential for agricultural biotechnology to contribute to food security. However, there has been limited application and adoption of new crop varieties in countries that are disproportionately affected by malnutrition and food insecurity.

The effect of DNA methylation on gene expression has been known for decades. However, the mechanism by which DNA methylation functions to repress transcription has remained a major question in the field. Wang et al. now narrow this gap through their examination of the methylation binding protein MBD2 and expose how DNA methylation is read upstream of transcriptional repression.

Leaf ecophysiological traits of crops are primarily inherited from their wild progenitors, challenging the conventional assumption that the origins of fast physiology lie only in early domestication and modern breeding.

Splicing is important for regulation of gene expression programmes, including those involved in plant development or plant environmental responses. In our study, we report that GRP20 regulates Arabidopsis gene expression by ensuring the proper splicing of thousands of floral and leaf RNAs, including the retention of micro exons in conserved floral homeotic genes. GRP20 binds to RNAs and interacts with the spliceosome, and both events are required for normal splicing and flower development.

Transposable element proliferation poses considerable threats to genomes. A previously unknown methyl reader, MBD2, represses transposable elements during male gametogenesis. MBD2 acts with a high degree of redundancy with other silencing pathways, together preserving genome stability.

In this study, Gómez-Fernández and colleagues show that crops were selected from wild progenitors with productive ecophysiological traits, conflicting with the hypothesis that these resource-acquisitive traits are a result of human domestication.

In this study, De Niu et al. report a two-step molecular mechanism, embryonic resetting of cold-induced TaVRN1 activation and subsequent TaVRN2 reactivation by light during seed germination, to re-establish vernalization requirements in wheat.

Feng and Zhang et al. develop a micrografting technique for conifer trees allowing distant relatives to join. Grafting in conifers uses a similar process to that in eudicots, and by introducing a conifer graft regulator to Arabidopsis, grafting and regeneration are enhanced.

Splicing of transcripts containing micro and small exons requires specific factors. This study shows that GRP20 regulates micro- and small-exon retention of transcripts including floral homeotic genes, whose splicing is crucial for flower development.

This study demonstrates an efficient method for capturing key regulators of target genes named CASPA–dCas9. With this method, the authors uncover the precise regulatory mechanism and key factors controlling SERRATE expression in Arabidopsis.

The microtubule-associated protein MIDD1 fine-tunes the secondary cell wall patterns in xylem vessels by forming co-condensates with KINESIN-13A, which induces the massive catastrophe of microtubules, in Arabidopsis thaliana.

Plant roots can respond to the environment by modifying cell type development. Here, the molecular pathways controlling root exodermal suberin are defined, as is its role in drought response. Modulating exodermal suberin levels can be a target for improved plant environmental resilience.

Cuticular wax is crucial for plant development and environmental interaction. This study reveals the negative impact of nitrogen on cuticular wax via MdBT2–MdMYB106–MdCER2L1, thus uncovering a novel pathway for N-mediated wax biosynthesis in apple.

Ligand-gated ion channels can be desensitized to control signalling outputs. This study reports the calmodulin-mediated, Ca²⁺-dependent desensitization of plant GLR channels, revealing a negative feedback loop in the orchestration of plant systemic wound responses.

Using an mRNA live-imaging system, Luo and colleagues show that Arabidopsis rotamase cyclophilins specifically bind mobile mRNAs and hitchhike on organelle trafficking to transport intercellularly towards plasmodesmata.

Loading of specialized metabolites from maternal tissue into embryo requires coupled export and import processes. Using glucosinolate seed loading as a model, this study identified four critical barriers along the transport route from source to sink.

Xu et al. report structures of the Arabidopsis cytokinin importer AZG1 in the apo, trans-zeatin-bound, 6-benzyleaminopurine-bound and kinetin-bound states, and elucidate an elevator transport model for the AZG1-mediated cytokinin uptake.