Новости науки и практики // Сентябрь 2019

Cell-surface receptors enable perception of extracellular cytokinins

Here show that cytokinin perception by plasma membrane receptors is an effective path for cytokinin response in root cells.

https://www.biorxiv.org/content/10.1101/726125v1

Expression atlas of Selaginella moellendorffii provides insights into the evolution of vasculature, secondary metabolism and roots

Here present a gene expression atlas comprising all major organs, tissue types, and the diurnal gene expression profiles for S. moellendorffii. The atlas is part of the CoNekT-Plants database (conekt.plant.tools), which enables comparative transcriptomic analyses across two algae and seven land plants.

https://www.biorxiv.org/content/10.1101/744326v1

Drought stress in Arabidopsis species

The response of the three Arabidopsis species to soil dry-down reveals that they have evolved distinct strategies to face drought stress. These strategic differences are in agreement with the distinct ecological priorities of the stress-tolerant A. lyrata, the competitive A. halleri and the ruderal A. thaliana.

https://www.botany.one/2019/08/drought-stress-in-arabidopsis-species/

Coordinated circadian timing through the integration of local inputs in Arabidopsis thaliana

Plant clocks can be set locally by organ-specific inputs but coordinated globally via spatial waves of clock gene expression.

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3000407

Cytokinin functions as an asymmetric and anti-gravitropic signal in lateral roots

Signal peptide processing of Cytokinin Oxidase 2 (CKX2) affects its enzymatic activity and, thereby, determines the degradation of cytokinins in natural Arabidopsis thaliana accessions. Cytokinin signaling interferes with growth at the upper lateral root flank and thereby prevents downward bending.

https://www.nature.com/articles/s41467-019-11483-4

Lateral root formation in Arabidopsis: a well-ordered LRexit

Recent studies reveal that biomechanical interactions between the new primordia and overlying tissues impact on organ initiation and morphogenesis. We propose a new mechanism, termed the developmental traffic light model, to explain how mechanical signals influence the patterning of the LR primordium.

https://www.cell.com/trends/plant-science/fulltext/S1360-1385(19)30162-1

When a plant loses photosynthesis, what else does it lose?

Being able to ditch photosynthesis means there’s no need for green on the flower stalk. It does make the plant look pallid and unhealthy. You might think that the plant has altered its genes to reduce the presence of green, and you’d be half right. Gitte Petersen and colleagues looked at the effect of heterotrophy not on the genes of the plant, but instead on the genes of the plastids.

https://www.botany.one/2019/07/when-a-plant-loses-photosynthesis-what-else-does-it-lose/

Evolution of fast root gravitropism in seed plants

Interspecies complementation and protein domain swapping revealed functional innovations within the PIN family of auxin transporters leading to the evolution of gravitropism-specific PINs. The unique apical/shootward subcellular localization of PIN proteins is the major evolutionary innovation that connected the anatomically separated sites of gravity perception and growth response via the mobile auxin signal.

https://www.nature.com/articles/s41467-019-11471-8

https://ist.ac.at/en/news/when-plant-roots-learned-to-follow-gravity/

Mediating the trade-off - How plants decide between growth or defense

Plants experience a trade-off between growth and defence, being unable to do both simultaneously. It was hypothesised, that this was due to limited energy resources within plants. New findings show that the transcription factor HBl1 mediates growth and defence responses through the regulation of ROS homeostasis. The contrasting ROS requirements of the processes result in incompatibility between both pathways, explaining the growth-defence trade-off.

https://www.eurekalert.org/pub_releases/2019-08/liop-mtt082719.php

How plants measure their carbon dioxide uptake

Results indicate that when the water supply is good the ABA receptors evaluate the basic hormonal balance as quasi 'stress-free' and keep the stomata open for CO2 supply. When water is scarce, the drought stress receptors recognise the elevated ABA level and make the guard cells close the stomata to prevent the plant from drying out.

https://www.eurekalert.org/pub_releases/2019-08/uow-hpm082619.php

Scientists find precise control of terminal division during plant stomatal development

A research group found a genetic suppressor of flp stomatal defects. They found that RPA2a, a core subunit of Replication Protein A (RPA) complexes, acted downstream from the core cell cycle genes of CDKB1 to ensure terminal division during stomatal development and the formation of paired guard cells to create functional stomata units.

https://www.eurekalert.org/pub_releases/2019-08/caos-sfp082019.php

New biosensor provides insight into the stress behavior of plants

Researchers have developed a method with which they can further investigate an important messenger substance in plants -- phosphatidic acid. Using a new biosensor, they are able to track the activity of phosphatidic acid spatially and temporally for the first time and thus, investigate plants that are exposed to stress such as salty soils.

https://www.sciencedaily.com/releases/2019/08/190827095038.htm

Plant protection: Researchers develop new modular vaccination kit

Simple, fast and flexible: it could become significantly easier to vaccinate plants against viruses in future. Scientists have developed a new method for this purpose. It enables the rapid identification and production of precisely tailored substances that combat different pathogens.

https://www.sciencedaily.com/releases/2019/08/190821082252.htm

How plants synthesize salicylic acid

It is a stress hormone made by plants, which is essential for them to fight off damaging pathogens. What was not known, is how plants generated this hormone. Now, biologists have unraveled the biosynthesis of this crucial hormone.

https://www.sciencedaily.com/releases/2019/08/190813105447.htm

New signaling component important for plant symbiosis

A proteomics-based protein-protein interaction study has led to the discovery of proteins that interact with a legume receptor that mediates signal transduction from the plasma membrane to the nucleus. This shows how symbiotic signals from symbiotic bacteria are transmitted upon perception, ultimately leading to their accommodation within the host plant.

https://www.sciencedaily.com/releases/2019/08/190801142559.htm

Role of extensin arabinosylation in root defence

The authors provide evidence for a link between extensin arabinosylation and root defence, and propose a model to explain the importance of glycosylation in limiting invasion of root cells by pathogenic oomycetes.

https://www.botany.one/2019/08/role-of-extensin-arabinosylation-in-root-defence/

Loss of RNA integrity precedes loss of viability in dry-stored seeds

You can see how time affects germination, by measuring the proportion of seeds that germinate after time. But is there a way of examining seed viability without germinating them?

https://www.botany.one/2019/08/loss-of-rna-integrity-precedes-loss-of-viability-in-dry-stored-seeds/