TBL38 atypical homogalacturonan-acetylesterase activity and cell wall microdomain localization in Arabidopsis seed mucilage secretory cells.

Plant cell walls constitute complex polysaccharidic/proteinaceous networks whose biosynthesis and dynamics implicate several cell compartments. The synthesis and remodeling of homogalacturonan pectins involve Golgi-localized methylation/acetylation and subsequent cell wall-localized demethylation/deacetylation. So far, TRICHOME BIREFRINGENCE-LIKE (TBL) family members have been described as Golgi-localized acetyltransferases targeting diverse hemicelluloses or pectins.

Top five unanswered questions in plant cell surface research.

Plant cell wall researchers were asked their view on what the major unanswered questions are in their field. This article summarises the feedback that was received from them in five questions. In this issue you can find equivalent syntheses for researchers working on bacterial, unicellular parasite and fungal systems.

Genome wide association study of Arabidopsis seed mucilage layers at a regional scale.

The myxospermous species Arabidopsis thaliana extrudes a polysaccharidic mucilage from the seed coat epidermis during imbibition. The whole seed mucilage can be divided into a seed-adherent layer and a fully soluble layer, both layers presenting natural genetic variations. The adherent mucilage is variable in size and composition, while the soluble mucilage is variable in composition and physical properties.

Evolutionary Analysis of Six Gene Families Part of the Reactive Oxygen Species (ROS) Gene Network in Three Species.

Climate change is expected to intensify the occurrence of abiotic stress in plants, such as hypoxia and salt stresses, leading to the production of reactive oxygen species (ROS), which need to be effectively managed by various oxido-reductases encoded by the so-called ROS gene network. Here, we studied six oxido-reductases families in three species, as well as and , which are adapted to hypoxia and salt stress, respectively. Using available and new genomic data, we performed a phylogenomic analysis and compared RNA-seq data to study genomic and transcriptomic adaptations.

Peptidyl-tRNA hydrolase is the nascent chain release factor in bacterial ribosome-associated quality control.

Rescuing stalled ribosomes often involves their splitting into subunits. In many bacteria, the resultant large subunits bearing peptidyl-tRNAs are processed by the ribosome-associated quality control (RQC) apparatus that extends the C termini of the incomplete nascent polypeptides with polyalanine tails to facilitate their degradation. Although the tailing mechanism is well established, it is unclear how the nascent polypeptides are cleaved off the tRNAs.

Structural insights into the mechanism of overcoming Erm-mediated resistance by macrolides acting together with hygromycin-A.

The ever-growing rise of antibiotic resistance among bacterial pathogens is one of the top healthcare threats today. Although combination antibiotic therapies represent a potential approach to more efficiently combat infections caused by susceptible and drug-resistant bacteria, only a few known drug pairs exhibit synergy/cooperativity in killing bacteria. Here, we discover that well-known ribosomal antibiotics, hygromycin A (HygA) and macrolides, which target peptidyl transferase center and peptide exit tunnel, respectively, can act cooperatively against susceptible and drug-resistant bacteria.

Cell-wall microdomain remodeling controls crucial developmental processes.

Plant cell walls display cellular and subcellular specificities. At the subcellular level, wall regional territories with specific compositions are necessary for macroscopic developmental processes. These regional specificities were named differently throughout the years, and are unified here under the term 'cell-wall microdomains' that define the local composition and organization of wall polymers underlying territories of wall loosening and/or softening or stiffening.

Class III Peroxidases PRX01, PRX44, and PRX73 Control Root Hair Growth in .

Root hair cells are important sensors of soil conditions. They grow towards and absorb water-soluble nutrients. This fast and oscillatory growth is mediated by continuous remodeling of the cell wall.

Editorial for Special Issue: Research on Plant Cell Wall Biology.

Plant cells are surrounded by extracellular matrixes [...

Class III Peroxidases in Response to Multiple Abiotic Stresses in Pyrenean Populations.

constitute a plant-specific multigene family, where 73 genes have been identified in . These genes are members of the reactive oxygen species (ROS) regulatory network in the whole plant, but more importantly, at the root level. In response to abiotic stresses such as cold, heat, and salinity, their expression is significantly modified.

Apoplastic class III peroxidases PRX62 and PRX69 promote Arabidopsis root hair growth at low temperature.

Root Hairs (RHs) growth is influenced by endogenous and by external environmental signals that coordinately regulate its final cell size. We have recently determined that RH growth was unexpectedly boosted when Arabidopsis thaliana seedlings are cultivated at low temperatures. It was proposed that RH growth plasticity in response to low temperature was linked to a reduced nutrient availability in the media.

Effects of Dielectric Barrier Ambient Air Plasma on Two Brassicaceae Seeds: and .

We investigated low-temperature plasma effects on two Brassicaceae seeds ( and ) using dielectric barrier discharge in air. Comparisons of plasma treatments on seeds showed distinct responses on germination rate and speed. Optimal treatment time giving optimal germination is 15 min for with 85% increase compared to control after 48 h of germination and 1 min for with 75% increase compared to control after 32 h of germination.

Myxospermy Evolution in Brassicaceae: A Highly Complex and Diverse Trait with as an Uncommon Model.

The ability to extrude mucilage upon seed imbibition (myxospermy) occurs in several Angiosperm taxonomic groups, but its ancestral nature or evolutionary convergence origin remains misunderstood. We investigated seed mucilage evolution in the Brassicaceae family with comparison to the knowledge accumulated in . The myxospermy occurrence was evaluated in 27 Brassicaceae species.

Mixotrophy in aquatic plants, an overlooked ability.

Aquatic Embryophytes play a key role in the proper functioning of aquatic ecosystems, where carbon (inorganic and organic forms) is pivotal in biogeochemical processes. There is growing awareness that mixotrophy, the direct use of exogenous organic carbon by autotrophs, is a widespread phenomenon and that it has emerged recurrently in the evolution of many autotrophic lineages. Despite living in an environment providing organic matter and presenting many favourable predispositions, aquatic plants from the Embryophytes, except carnivorous ones, have never been deeply investigated for mixotrophy.

Highlighting reactive oxygen species as multitaskers in root development.

Reactive oxygen species (ROS) are naturally produced by several redox reactions during plant regular metabolism such as photosynthesis and respiration. Due to their chemical properties and high reactivity, ROS were initially described as detrimental for cells during oxidative stress. However, they have been further recognized as key players in numerous developmental and physiological processes throughout the plant life cycle.

CsPrx25, a class III peroxidase in Citrus sinensis, confers resistance to citrus bacterial canker through the maintenance of ROS homeostasis and cell wall lignification.

Citrus bacterial canker (CBC) results from Xanthomonas citri subsp. citri (Xcc) infection and poses a grave threat to citrus production. Class III peroxidases (CIII Prxs) are key proteins to the environmental adaptation of citrus plants to a range of exogenous pathogens, but the role of CIII Prxs during plant resistance to CBC is poorly defined.

Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits.

Mycorrhizal fungi are mutualists that play crucial roles in nutrient acquisition in terrestrial ecosystems. Mycorrhizal symbioses arose repeatedly across multiple lineages of Mucoromycotina, Ascomycota, and Basidiomycota. Considerable variation exists in the capacity of mycorrhizal fungi to acquire carbon from soil organic matter.

An integrative Study Showing the Adaptation to Sub-Optimal Growth Conditions of Natural Populations of : A Focus on Cell Wall Changes.

In the global warming context, plant adaptation occurs, but the underlying molecular mechanisms are poorly described. Studying natural variation of the model plant adapted to various environments along an altitudinal gradient should contribute to the identification of new traits related to adaptation to contrasted growth conditions. The study was focused on the cell wall (CW) which plays major roles in the response to environmental changes.

The Class III Peroxidase Encoding Gene Positively and Spatiotemporally Regulates the Low pH-Induced Cell Death in Roots.

Exogenous low pH stress causes cell death in root cells, limiting root development, and agricultural production. Different lines of evidence suggested a relationship with cell wall (CW) remodeling players. We investigated whether class III peroxidase (CIII Prx) total activity, CIII Prx candidate gene expression, and reactive oxygen species (ROS) could modify CW structure during low pH-induced cell death in roots.

A powerful framework for an integrative study with heterogeneous omics data: from univariate statistics to multi-block analysis.

High-throughput data generated by new biotechnologies require specific and adapted statistical treatment in order to be efficiently used in biological studies. In this article, we propose a powerful framework to manage and analyse multi-omics heterogeneous data to carry out an integrative analysis. We have illustrated this using the mixOmics package for R software as it specifically addresses data integration issues.

Coordination of five class III peroxidase-encoding genes for early germination events of Arabidopsis thaliana.

The Class III peroxidases (CIII Prxs) belong to a plant-specific multigene family. Thanks to their double catalytic cycle they can oxidize compounds or release reactive oxygen species (ROS). They are either involved in different cell wall stiffening processes such as lignification and suberization, in cell wall loosening or defense mechanisms.

Seed mucilage evolution: Diverse molecular mechanisms generate versatile ecological functions for particular environments.

Plant myxodiasporous species have the ability to release a polysaccharidic mucilage upon imbibition of the seed (myxospermy) or the fruit (myxocarpy). This is a widespread capacity in angiosperms providing multiple ecological functions including higher germination efficiency under environmental stresses. It is unclear whether myxodiaspory has one or multiple evolutionary origins and why it was supposedly lost in several species.

Plant Cell Wall Proteins and Development.

Plant cell walls surround cells and provide both external protection and a means of cell-to-cell communication [...