Sweet modifications modulate plant development

Plant development represents a continuous process in which the plant undergoes morphological, (epi)genetic and metabolic changes. Starting from pollination, seed maturation and germination, the plant continues to grow and develops specialized organs to survive, thrive and generate offspring. The development of plants and the interplay with its environment are highly linked to glycosylation of proteins and lipids as well as metabolism and signaling of sugars. Although the involvement of these protein modifications and sugars is well-studied, there is still a long road ahead to profoundly comprehend their nature, significance, importance for plant development and the interplay with stress responses. This review, approached from the plants' perspective, aims to focus on some key findings highlighting the importance of glycosylation and sugar signaling for plant development

Shotgun proteomics of peach fruit reveals major metabolic pathways associated to ripening

Indexación ScopusBackground: Fruit ripening in Prunus persica melting varieties involves several physiological changes that have a direct impact on the fruit organoleptic quality and storage potential. By studying the proteomic differences between the mesocarp of mature and ripe fruit, it would be possible to highlight critical molecular processes involved in the fruit ripening. Results: To accomplish this goal, the proteome from mature and ripe fruit was assessed from the variety O’Henry through shotgun proteomics using 1D-gel (PAGE-SDS) as fractionation method followed by LC/MS-MS analysis. Data from the 131,435 spectra could be matched to 2740 proteins, using the peach genome reference v1. After data pre-treatment, 1663 proteins could be used for comparison with datasets assessed using transcriptomic approaches and for quantitative protein accumulation analysis. Close to 26% of the genes that code for the proteins assessed displayed higher expression at ripe fruit compared to other fruit developmental stages, based on published transcriptomic data. Differential accumulation analysis between mature and ripe fruit revealed that 15% of the proteins identified were modulated by the ripening process, with glycogen and isocitrate metabolism, and protein localization overrepresented in mature fruit, as well as cell wall modification in ripe fruit. Potential biomarkers for the ripening process, due to their differential accumulation and gene expression pattern, included a pectin methylesterase inhibitor, a gibbellerin 2-beta-dioxygenase, an omega-6 fatty acid desaturase, a homeobox-leucine zipper protein and an ACC oxidase. Transcription factors enriched in NAC and Myb protein domains would target preferentially the genes encoding proteins more abundant in mature and ripe fruit, respectively. Conclusions: Shotgun proteomics is an unbiased approach to get deeper into the proteome allowing to detect differences in protein abundance between samples. This technique provided a resolution so that individual gene products could be identified. Many proteins likely involved in cell wall and sugar metabolism, aroma and color, change their abundance during the transition from mature to ripe fruit. © 2021, The Author(s).https://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-020-07299-

Cell Signaling in Model Plants

This book provides new and in-depth insights into molecular aspects of plant cell signaling in response to biotic, such as aphid- and grey mold disease-resistance, and abiotic stresses, such as soil salinity and drought stress, and additionally, functional analysis on signaling components involved in flowering, juvenility, GA signaling, and biosynthesis, and miRNA-regulated gene expression. Furthermore, plant acclimation was reported, with emphasis on mechanistic insights into the roles of brassinosteroids, cyclic AMP, and hydrogen sulfide, and the recent advances of transmembrane receptor-like kinases were refined. Clearly, plant cell signaling is an intensive topic and whether it is now or in the future, the emerging technology in functional analysis such as genome editing technologies, high-throughput technologies, integrative multiple-omics as well as bioinformatics can assist researchers to reveal novel aspects of the regulatory mechanisms of plant growth and development, and acclimation to environmental and biotic stresses. The achievement of such research will be useful in improving crop stress tolerances to increase agricultural productivity and sustainability for the food supply of the world

Autophagy in plants

Autophagy is a process of cellular self-eating, which allows organisms to eliminate and recycle unwanted components and damaged organelles to maintain cellular homeostasis. It is an important process in the development of eukaryotic organisms. Autophagy plays a critical role in many physiological processes in plants such as nutrient remobilization, cell death, immunity, and abiotic stress responses. Autophagy thus represents an obvious target for generating resilient crops. During plant development, autophagy is also implicated in the differentiation and maturation of various cell types and plant organs, including root cap cells, tracheary elements, gametes, fruits and seeds. Here, we review our current understanding and recent advances of plant autophagy including insight into autophagy regulation and signaling as well as autophagosome membrane biogenesis. In addition, we describe how autophagy contributes to development, metabolism, biotic and abiotic stress tolerance and where the autophagic field is heading in terms of applied research for crop improvement

Malectin-like receptor-like kinases mediate pollen tube reception in Arabidopsis thaliana

Development of plant organs requires constant monitoring of endogenous and environmental cues for which plant cells have evolved a wide array of sensors. Among them, the receptor-like kinase (RLK) family is of particular relevance for plants due to its remarkable expansion during plant evolution. RLKs sense exogenous and endogenous signals, controlling a myriad of processes such as responses to hormones and pathogens. The Catharanthus roseus RLK 1-like (CrRLK1L) group of RLKs is known to control immunity and developmental processes like reproduction and cell expansion, and have been postulated to act as signalling hubs in which several cellular pathways converge. This is best exemplified by its most studied member, FERONIA (FER), a receptor of rapid alkalinisation factor (RALF) peptides and cell wall components, and a mediator of receptor complex assembly during pathogen perception. In this project the Arabidopsis CrRLK1L receptor family was examined with the goal of identifying novel functions in plant development for uncharacterised or already characterised members. A CrRLK1L T-DNA mutant set was obtained and several higher order mutants generated to reveal defects masked by functional redundancy between related CrRLK1Ls. Initial screens identified roles for HERCULES RECEPTOR KINASE 1 (HERK1), HERK2 and THESEUS1 (THE1) in abscisic acid signalling during germination and a role during reproduction for HERK1 and its uncharacterised homolog ANJEA (ANJ). Further experiments confirmed the involvement of HERK1 and ANJ in controlling pollen tube reception in the ovule. HERK1 and ANJ were found to localise in the filiform apparatus of the synergid cells, to influence the relocalisation of NORTIA after pollen tube arrival and to physically associate with LORELEI. Additionally, the Arabidopsis RALF family was probed to identify regulators of reproduction, yielding the identification of peptides RALFL4 and RALFL19 as determinants of pollen tube growth stability

The lowdown on breakdown: Open questions in plant proteolysis.

Proteolysis, including post-translational proteolytic processing as well as protein degradation and amino acid recycling, is an essential component of the growth and development of living organisms. In this article, experts in plant proteolysis pose and discuss compelling open questions in their areas of research. Topics covered include the role of proteolysis in the cell cycle, DNA damage response, mitochondrial function, the generation of N-terminal signals (degrons) that mark many proteins for degradation (N-terminal acetylation, the Arg/N-degron pathway, and the chloroplast N-degron pathway), developmental and metabolic signaling (photomorphogenesis, abscisic acid and strigolactone signaling, sugar metabolism, and postharvest regulation), plant responses to environmental signals (endoplasmic-reticulum-associated degradation, chloroplast-associated degradation, drought tolerance, and the growth-defense trade-off), and the functional diversification of peptidases. We hope these thought-provoking discussions help to stimulate further research

Plant Physiology, Development and Metabolism

Water is one of the most important constituents of life. Chemically, water is the hydride of oxygen. Oxygen, being more electronegative, exerts a strong attractive pull on its electrons. This unequal attraction results in small positive charge on twohydrogenmoleculesandasmallnegativechargeontheoxygenmolecule.The two lone pairs of electrons of the oxygen molecule result in bending of water molecule. The partial charges on oxygen and hydrogen molecules result in high electric dipole moment and polarity of water molecule