Новости науки и практики // Апрель 2020

Ethylene sensor could help monitor plant health
To control flowering and fruit ripening, plants release the gaseous hormone ethylene. Environmental conditions, including drought, salinity and pathogens, can also cause levels of the hormone to fluctuate. Therefore, monitoring ethylene's release in real time could provide a farmer with important information about a plant's development and health.
https://www.eurekalert.org/pub_releases/2020-03/acs-esc031320.php

У регуляторных РНК ищут контакты с ДНК
Новый метод поиска контактов между РНК и ДНК поможет лучше понять, как РНК влияет на активность генов.
https://www.nkj.ru/news/38404/

A molecular map for the plant sciences
First comprehensive map of the proteome of the model plant Arabidopsis thaliana.
https://www.eurekalert.org/pub_releases/2020-03/tuom-amm031120.php

How plants protect themselves from sun damage
Study reveals a mechanism that plants can use to dissipate excess sunlight as heat.
https://www.eurekalert.org/pub_releases/2020-03/miot-hpp030620.php

Identification of a plant kinase that phosphorylates the bacterial effector AvrPtoB
A critical component controlling bacterial virulence is the delivery of pathogen effectors into plant cells during infection. Effectors alter host metabolism and immunity for pathogen benefit. Multiple effectors are phosphorylated by host kinases, and this posttranslational modification is important for their activity. Lei et al. sought to identify host kinases involved in effector phosphorylation.
https://www.biorxiv.org/content/10.1101/2020.03.21.001826v1.full.pdf+html

C2 photosynthesis: a promising route towards crop improvement?
Scientists argues that engineering C2 photosynthesis into C3 crops is a promising approach to improve photosynthetic performance under these – and temporally heterogeneous – environments, and review the modifications that may re‐create a C2 phenotype in C3 plants.
https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.16494

Leaf trichomes may avoid water stress in part by impeding gall formation
Trichomes seem to help prevent the larger gall types that lead to greater water loss.
https://www.botany.one/2020/03/leaf-trichomes-may-avoid-water-stress-in-part-by-impeding-gall-formation/

Mitochondria and stress signalling
How tiny heroes are connected in signalling stress.
https://www.botany.one/2020/03/mitochondria-and-stress-signalling/

Gene Dosage Balance Immediately Following Whole-Genome Duplication in Arabidopsis thaliana
Flowering plants have witnessed multiple cycles of whole-genome duplication (WGD) over the past 200 million years of evolution. Typically, WGD increases genome size and gene content, followed by gene loss, or fractionation, depending on functional categories.
http://www.plantcell.org/content/early/2020/03/17/tpc.20.00205

A cross-kingdom conserved ER-phagy receptor maintains endoplasmic reticulum homeostasis during stress
Eukaryotes have evolved various quality control mechanisms to promote proteostasis in the ER. Selective removal of certain ER domains via autophagy (termed as ER-phagy) has emerged as a major quality control mechanism. However, the degree to which ER-phagy is employed by other branches of ER-quality control remains largely elusive. Stephani et al. identify a cytosolic protein, C53, that is specifically recruited to autophagosomes during ER-stress, in both plant and mammalian cells. C53 interacts with ATG8 via a distinct binding epitope, featuring a shuffled ATG8 interacting motif (sAIM).
https://www.biorxiv.org/content/10.1101/2020.03.18.995316v1.full.pdf

SCHENGEN receptor module drives localized ROS production and lignification in plant roots
Fujita et al. establish a kinase signaling relay that exerts direct, spatial control over ROS production and lignification within the cell wall. We show that polar localization of a single kinase component is crucial for pathway function. Their data indicate that an intersection of more broadly localized components allows for micrometer‐scale precision of lignification and that this system is triggered through initiation of ROS production as a critical peroxidase co‐substrate.
https://www.embopress.org/doi/10.15252/embj.2019103894

How plants protect themselves from sun damage
Study reveals a mechanism that plants can use to dissipate excess sunlight as heat.
https://www.sciencedaily.com/releases/2020/03/200310094246.htm

Structural insights into catalytic mechanism and product delivery of cyanobacterial acyl-acyl carrier protein reductase
Results reveal the binding pattern of AAR (acyl-acyl carrier protein (acyl-ACP) reductase) with its substrate/cofactor, and suggest a potential aldehyde-transferring channel from AAR to ADO (aldehyde-deformylating oxygenase). Based on our structural and biochemical data, we proposed a model for the complete catalytic cycle of AAR.
https://www.nature.com/articles/s41467-020-15268-y

A signal cascade originated from epidermis defines apical-basal patterning of Arabidopsis shoot apical meristems
Scientists uncover that epidermis specific transcription factors, ARABIDOPSIS THALIANA MERISTEM LAYER 1 (ATML1) and its close homolog, define the concentration gradient of HAM (HAIRY MERISTEM) in the SAM (shoot apical meristem) through activating a group of microRNAs. This study provides a molecular framework linking the epidermis-derived signal to the stem cell homeostasis in plants.
https://www.nature.com/articles/s41467-020-14989-4

Diatoms synthesize sterols by inclusion of animal and fungal genes in the plant pathway
Phylogenetic comparison revealed a good level of similarity between the sterol biosynthetic genes of S. marinoi and C. cryptica with those in the genomes of the other diatoms sequenced so far.
https://www.nature.com/articles/s41598-020-60993-5

Delayed aluminium exclusion in signal grass is energy-dependent
Signal grass has a high aluminium resistance, though the mechanism of this resistance is not well understood. Furthermore, full resistance occurs only after a 24-48 hour delay, which is preceded by a phase in which the roots are sensitive to the metal.
https://www.botany.one/2020/03/delayed-aluminium-exclusion-in-signal-grass-is-energy-dependent/

Expression of the sesame MYB transcription factor SiMYB305 boosts tolerance to drought and salt stress in Arabidopsis
MYBs are a vital gene family with a large number of members which modulate various biological processes in plants including shoot growth and root formation. They have also attracted attention in various plant species for their involvement in plant abiotic stress tolerance. However, MYBs have yet to be fully investigated in sesame, an important oil crop grown largely in areas highly susceptible to drought and salt stress.
https://www.botany.one/2020/03/expression-of-the-sesame-myb-transcription-factor-simyb305-boosts-tolerance-to-drought-and-salt-stress-in-arabidopsis/

The SAUR41 subfamily of genes is involved in cell expansion and salt tolerance
The SAUR (SMALL AUXIN UP RNA) family of genes is one of three families of auxin-response genes, and is relatively understudied compared to the other two. A subfamily of SAUR genes called SAUR41 contains four different individual genes and has been found through data mining to be induced by the hormone abscisic acid (ABA), though its exact function is unknown. Scientists used the gene-editing system CRISPR/Cas9 to produce mutants both without SAUR41 expression (that is, a quadruple mutant) and with the genes over-expressed, with the goal of determining their function.
https://www.botany.one/2020/03/the-saur41-subfamily-of-genes-is-involved-in-cell-expansion-and-salt-tolerance/

Root flavonoids are related to enhanced AMF colonization of an invasive tree
One hypothesis suggests that invasive species can alter the AMF (arbuscular mycorrhizal fungi) community and receive greater benefits compared to co-occurring native plants. This would promote their invasion by increasing survival, growth rate and/or competitiveness. Alteration of the AMF community is likely facilitated by the exudation of secondary compounds from the roots. However, there have been no investigations of the regulation of AMF by secondary chemicals in invasive plants.
https://www.botany.one/2020/03/root-flavonoids-are-related-to-enhanced-amf-colonization-of-an-invasive-tree/

Rice chloroplasts become more spherical under salt stress
Scientists examined the leaves of rice plants that had been treated with saline solution. The authors used focussed ion beam scanning electron microscopy (FIB-SEM) and image processing software to reconstruct the 3-D ultrastructure of the mesophyll cells and their organelles. In control cells, chloroplasts were lens-shaped and arranged closely along the cell wall. In the salt-treated cells, however, the chloroplasts became more oval-shaped, but with no overall change in volume, though the surface area to volume ratio decreased.
https://www.botany.one/2020/03/rice-chloroplasts-become-more-spherical-under-salt-stress/

How plants sound the alarm about danger
Scientists provides a detailed picture of how plant hormones communicate through gene regulation.
https://www.eurekalert.org/pub_releases/2020-03/si-hps031320.php

Plant physiology: Safeguarding chloroplasts from sunburn
Using thale cress (Arabidopsis thaliana) as a model system, biologists have characterized a previously unknown signaling pathway that makes a significant contribution to stress tolerance and suppresses light-induced programmed cell death. This pathway could potentially be exploited to improve stress resistance in crop plants.
https://www.eurekalert.org/pub_releases/2020-03/lm-pps031220.php