Volume 9 Issue 6, June 2023

The regulatory networks that underlie the regeneration capacity of wheat reveal new opportunities for overcoming barriers to highly efficient and genotype-independent transformation.

The new structure for the H⁺-coupled sucrose uptake transporter AtSUC1 helps us understand the mechanism used by plants for cellular sucrose uptake and phloem loading.

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.

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.

Pollen coat is important in protecting plant male gametes. The authors review genes and proteins involved in its biosynthesis, transport and regulation processes in rice and Arabidopsis, and highlight the usage of pollen coat-deficient mutants in plant breeding.

In plants, mechanically triggered signalling cascades involve intracellular calcium waves. The kinetics of waves induced by the application and release of force to a cell are distinct, suggesting that plants distinguish touch from letting go.

Strigolactone (SL) regulates plant development. Structural analysis shows that when SL binds its receptor ShHTL5, conformational changes occur including the creation of internal tunnels that posit an explanation for how SL by-products exit the receptor after signalling.

The partitioning membrane of dividing plant cells is made by vesicle fusion, involving complex-forming membrane-anchored SNARE proteins. The authors show that the disassembly of cis-SNARE complexes by NSF ATPase enables the formation of trans-SNARE complexes, which mediates vesicle fusion.

Old trees have many ecological and socio-cultural values that affect their survival. Species with greater potential height, smaller leaf size and diverse human utilization attributes had the highest probability of long-term persistence.

Wheat functional genomics is limited by low transformation efficiency. This study uncovered the transcriptional regulatory network responsible for wheat regeneration and identified two DOF transcription factors that can enhance regeneration in wheat.

Plant specialized metabolite biosynthesis is strictly regulated in time and space. The authors describe a robust and redundant transcriptional network that steers cell-specific and jasmonate-inducible triterpene biosynthesis in Arabidopsis root tips.

The crystal structure of the Arabidopsis sucrose–proton symporter SUC1 is presented at 2.7 Å resolution. This allows the identification of a proton-driven symport process for SUC1 that may help in understanding how low-affinity transport can occur in enriched substrate environments.

Sugar signalling plays vital roles in cellular function. This study discovered that MdERDL6-mediated glucose elevation in cytosol activates the SnRK2.3-AREB1-TST1/2 cascade to promote sugar accumulation in the vacuoles of apple and tomato fruits.

Suppressing wheat ASPARTIC PROTEASE 1 promotes the homeostasis of PsbO, stabilizes the photosystem complex and elongates the duration of active photosynthesis, leading to increases in the CO₂ assimilation rate, kernel weight and yield.

To advance crop productivity improvement efforts, the authors integrated crystal structure-guided changes from a highly effective red algae Rubisco into a related bacterial enzyme to improve its CO₂-fixing traits that, in tobacco, enhanced photosynthesis and growth.

A 2.2 Å cryo-electron microscopy structure of an actively translating 80S ribosome from tobacco reveals bound tRNA and mRNA, the nascent peptide and numerous cofactors, providing a basis for understanding the molecular mechanism of protein synthesis in plants.