Selective recognition of PTRE1 transcripts mediated by protein-protein interaction between the mA reader ECT2 and PTRE1.

N-methyladenosine (mA) is a prevalent internal post-transcriptional modification in eukaryotic RNAs executed by mA-binding proteins known as "readers." Our previous research demonstrated that the Arabidopsis mA reader ECT2 positively regulates transcript levels of the proteasome regulator PTRE1 and several 20S proteasome subunits, thereby enhancing 26S proteasome activity. However, mechanism underlying the selective recognition of mA targets by readers, such as ECT2, remains elusive.

Enhanced Production of Aromatic Amino Acids in Tobacco Plants Leads to Increased Phenylpropanoid Metabolites and Tolerance to Stresses.

Aromatic amino acids (AAAs) synthesized in plants via the shikimate pathway can serve as precursors for a wide range of secondary metabolites that are important for plant defense. The goals of the current study were to test the effect of increased AAAs on primary and secondary metabolic profiles and to reveal whether these plants are more tolerant to abiotic stresses (oxidative, drought and salt) and to (Egyptian broomrape), an obligate parasitic plant. To this end, tobacco () plants were transformed with a bacterial gene (AroG) encode to feedback-insensitive 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, the first enzyme of the shikimate pathway.

ATI1 (ATG8-interacting protein 1) and ATI2 define a plant starvation-induced reticulophagy pathway and serve as MSBP1/MAPR5 cargo receptors.

Reticulophagy, the selective autophagy of endoplasmic reticulum (ER) components, is known to operate in eukaryotes from yeast and unicellular algae to animals and plants. Thus far, only ER-stress induced reticulophagy was reported and analyzed in plants. In this study we characterize a reticulophagy pathway in that is triggered by dark-induced starvation but not by ER stress.

The m A reader ECT2 post-transcriptionally regulates proteasome activity in Arabidopsis.

Methylation of internal adenosine at nitrogen-6 position (m A) is the most abundant post-transcriptional modification in eukaryotic RNAs. These modifications are recognized by m A-binding proteins ('readers') that affect downstream functions. In plants, the scope of gene expression regulation by reader proteins is not clear.

Increased phenylalanine levels in plant leaves reduces susceptibility to Botrytis cinerea.

Botrytis cinerea is a major plant pathogen, causing losses in crops during growth and storage. Here we show that increased accumulation of phenylalanine (Phe) and Phe-derived metabolites in plant leaves significantly reduces their susceptibility to B. cinerea.

The viral F-box protein P0 induces an ER-derived autophagy degradation pathway for the clearance of membrane-bound AGO1.

RNA silencing is a major antiviral defense mechanism in plants and invertebrates. Plant ARGONAUTE1 (AGO1) is pivotal in RNA silencing, and hence is a major target for counteracting viral suppressors of RNA-silencing proteins (VSRs). P0 from (TuYV) is a VSR that was previously shown to trigger AGO1 degradation via an autophagy-like process.

Tuning the Orchestra: miRNAs in Plant Immunity.

miRNAs act as negative modulators of target genes and play key roles in post-transcriptional gene regulation through sequence-specific mRNA cleavage and translational inhibition. Two recent reports highlight the orchestrated role of miRNA2111 and miRNA172b in plant innate immunity [1,2] (Science 2018;362:233-236; Plant Cell 2018;30:2779-2794).

An L,L-diaminopimelate aminotransferase mutation leads to metabolic shifts and growth inhibition in Arabidopsis.

Lysine (Lys) connects the mitochondrial electron transport chain to amino acid catabolism and the tricarboxylic acid cycle. However, our understanding of how a deficiency in Lys biosynthesis impacts plant metabolism and growth remains limited. Here, we used a previously characterized Arabidopsis mutant (dapat) with reduced activity of the Lys biosynthesis enzyme L,L-diaminopimelate aminotransferase to investigate the physiological and metabolic impacts of impaired Lys biosynthesis.

The metabolic roles of free amino acids during seed development.

Amino acids play vital roles in the central metabolism of seeds. They are primarily utilized for the synthesis of seed-storage proteins, but also serve as precursors for the biosynthesis of secondary metabolites and as a source of energy. Here, we aimed at describing the knowledge accumulated in recent years describing the changes occurring in the contents of free amino acids (FAAs) during seed development.

Autophagy-related approaches for improving nutrient use efficiency and crop yield protection.

Autophagy is a eukaryotic catabolic pathway essential for growth and development. In plants, it is activated in response to environmental cues or developmental stimuli. However, in contrast to other eukaryotic systems, we know relatively little regarding the molecular players involved in autophagy and the regulation of this complex pathway.

New insights into the metabolism of aspartate-family amino acids in plant seeds.

Aspartate-family amino acids. Aspartate (Asp)-family pathway, via several metabolic branches, leads to four key essential amino acids: Lys, Met, Thr, and Ile. Among these, Lys and Met have received the most attention, as they are the most limiting amino acid in cereals and legumes crops, respectively.

Fluorescence Imaging of Autophagy-Mediated ER-to-Vacuole Trafficking in Plants.

Macroautophagy (hereafter referred to as autophagy) is a conserved mechanism in eukaryotic cells that delivers unneeded cellular components for degradation in the lytic organelle. In plants, as in other eukaryotes, autophagy begins in the formation of cup-shaped double membranes that engulf cytosolic material. The double membrane closes to form autophagosomes that are then transported to the vacuole for degradation.

Phenylpyruvate Contributes to the Synthesis of Fragrant Benzenoid-Phenylpropanoids in × Flowers.

Phenylalanine (Phe) is a precursor for a large group of plant specialized metabolites, including the fragrant volatile benzenoid-phenylpropanoids (BPs). In plants, the main pathway leading to production of Phe is arogenate, while the pathway phenylpyruvate (PPY) is considered merely an alternative route. Unlike plants, in most microorganisms the only pathway leading to the synthesis of Phe is PPY.

Altered metabolite accumulation in tomato fruits by coexpressing a feedback-insensitive AroG and the PhODO1 MYB-type transcription factor.

Targeted manipulation of phenylalanine (Phe) synthesis is a potentially powerful strategy to boost biologically and economically important metabolites, including phenylpropanoids, aromatic volatiles and other specialized plant metabolites. Here, we use two transgenes to significantly increase the levels of aromatic amino acids, tomato flavour-associated volatiles and antioxidant phenylpropanoids. Overexpression of the petunia MYB transcript factor, ODORANT1 (ODO1), combined with expression of a feedback-insensitive E.

hfAIM: A reliable bioinformatics approach for in silico genome-wide identification of autophagy-associated Atg8-interacting motifs in various organisms.

Most of the proteins that are specifically turned over by selective autophagy are recognized by the presence of short Atg8 interacting motifs (AIMs) that facilitate their association with the autophagy apparatus. Such AIMs can be identified by bioinformatics methods based on their defined degenerate consensus F/W/Y-X-X-L/I/V sequences in which X represents any amino acid. Achieving reliability and/or fidelity of the prediction of such AIMs on a genome-wide scale represents a major challenge.

Metabolic Engineering of the Phenylpropanoid and Its Primary, Precursor Pathway to Enhance the Flavor of Fruits and the Aroma of Flowers.

Plants produce a diverse repertoire of specialized metabolites that have multiple roles throughout their life cycle. Some of these metabolites are essential components of the aroma and flavor of flowers and fruits. Unfortunately, attempts to increase the yield and prolong the shelf life of crops have generally been associated with reduced levels of volatile specialized metabolites and hence with decreased aroma and flavor.

Autophagy in Plants--What's New on the Menu?

Autophagy is a major cellular degradation pathway in eukaryotes. Recent studies have revealed the importance of autophagy in many aspects of plant life, including seedling establishment, plant development, stress resistance, metabolism, and reproduction. This is manifested by the dual ability of autophagy to execute bulk degradation under severe environmental conditions, while simultaneously to be highly selective in targeting specific compartments and protein complexes to regulate key cellular processes, even during favorable growth conditions.

The transporter GAT1 plays an important role in GABA-mediated carbon-nitrogen interactions in Arabidopsis.

Glutamate derived γ-aminobutyric acid (GABA) is synthetized in the cytosol prior to delivery to the mitochondria where it is catabolized via the TCA cycle. GABA accumulates under various environmental conditions, but an increasing number of studies show its involvement at the crossroad between C and N metabolism. To assess the role of GABA in modulating cellular metabolism, we exposed seedlings of A.

Phenylalanine and tyrosine levels are rate-limiting factors in production of health promoting metabolites in Vitis vinifera cv. Gamay Red cell suspension.

Environmental stresses such as high light intensity and temperature cause induction of the shikimate pathway, aromatic amino acids (AAA) pathways, and of pathways downstream from AAAs. The induction leads to production of specialized metabolites that protect the cells from oxidative damage. The regulation of the diverse AAA derived pathways is still not well understood.