Volume 8 Issue 4, April 2022

Extensive genetics and genomics analyses reveal the co-transcriptional processing mode of primary substrates of microRNAs in Arabidopsis, and an unexpected promoting role of R-loops in the process.

Theory predicts duplicate genes will evolve new functions or be lost from genomes rather than maintain redundant functions. Kwon et al. show that redundant plant genes can be maintained if they actively compensate for perturbation of their partners at the shoot tip, but that this might not be an evolutionarily stable strategy to stave off degenerative mutations.

Genome sequences and expression data for partly and wholly mycoheterotrophic orchids shed light on shifts in nuclear genes that may help drive dependence on fungi for carbon.

The first complete cycad genome offers an invaluable solution to sex determination, one of the largest conservation challenges in these enigmatic plants.

By sequencing and analyzing the genomes of the partially and fully mycoheterotrophic orchids Platanthera zijinensis and P. guangdongensis, respectively, we reveal not only the potential molecular basis underlying important mycoheterotrophic traits, but also nutrient supplement mechanisms in the early and later stage of mycoheterotrophic growth, illuminating the evolution of mycoheterotrophic plants.

Xylan-rich nanodomains at pit borders of xylem vessels determine a pitted wall pattern by anchoring cellulosic nanofibrils at the pit edges and are crucial to support vessel robustness, water transport and leaf transpiration. These nanocompartments are mostly produced by the de novo xylan synthase IRREGULAR XYLEM (IRX)10 and its homologues.

Homogalacturonans are the most abundant pectin subtype in plant cell walls and also function as signalling molecules. Homogalacturonans thus connect the cell wall and plasma membrane to regulate plant growth and development.

This analysis looks at water use efficiency within and across multiple regions with different plant functional types, and finds that water use efficiency values tend to converge for some types despite distinct geographic and climatic zones.

Gene duplication and subsequent paralogue diversification shape phenotypes. This study shows how paralogues controlling stem cell proliferation evolve over short time scales and provides an evo-devo perspective for trait engineering in crop design.

Membrane receptor kinases are involved in many signalling pathways in plants. Here, the authors show that a common mechanism, consisting of a RLCK kinase and a PP2C phosphatase, regulates signalling downstream of receptors, both in immunity and development.

Contrary to expectations that a warmer planet from climate change would be good for cactus species, this analysis of 400 species under three climate scenarios finds that over half may experience a reduction in their suitable climate, challenging perceptions of impacts for this plant family around the world

Analyses of the genome sequences and expression data for two closely related mycoheterotrophic orchid species provide insights into the genomic basis underlying the evolution of mycoheterotrophy.

The study assembled a chromosome-level genome of Cycas panzhihuaensis, the last major lineage of seed plants for which a high-quality genome assembly was lacking. The study closes an important gap in our understanding of genome structure and evolution in seed plants.

This study demonstrates that the processing of miRNAs in plants can occur coupled to transcription, post-transcriptionally or as a mixture of both in a process promoted by DNA–RNA hybrids upstream from the transcription start site of miRNA loci.

In tomato, the transcription factor DOF9 regulates inflorescence termination and flower development, which determines fruit yield. DOF9 is connected to the auxin signalling pathway through ARF5.

Heat sensing is not well understood in plants. Here the authors show that high temperature induces the production of nitric oxide conjugate S-nitrosoglutathione in the shoot meristem. A systemic long-distance signalling pathway then includes nitrosylation of transcription factor GT-1, which activates heat-responsive genes such as HsfA2.