Mitochondrial Biogenesis in Diverse Cauliflower Cultivars under Mild and Severe Drought. Impaired Coordination of Selected Transcript and Proteomic Responses, and Regulation of Various Multifunctional Proteins

Oncolytic Newcastle disease virus induced degradation of YAP through E3 ubiquitin ligase PRKN to exacerbate ferroptosis in tumor cells

Ferroptosis, a form of programmed cell death characterized by iron-dependent lipid peroxidation, has recently gained considerable attention in the field of cancer therapy. There is significant crosstalk between ferroptosis and several classical signaling pathways, such as the Hippo pathway, which suppresses abnormal growth and is frequently aberrant in tumor tissues. Yes-associated protein 1 (YAP), the core effector molecule of the Hippo pathway, is abnormally expressed and activated in a variety of malignant tumor tissues. We previously proved that the oncolytic Newcastle disease virus (NDV) activated ferroptosis to kill tumor cells. NDV has been used in tumor therapy; however, its oncolytic mechanism is not completely understood. In this study, we demonstrated that NDV exacerbated ferroptosis in tumor cells by inducing ubiquitin-mediated degradation of YAP at Lys90 through E3 ubiquitin ligase parkin (PRKN). Blocking YAP degradation suppressed NDV-induced ferroptosis by suppressing the expression of Zrt/Irt-like protein 14 (ZIP14), a metal ion transporter that regulates iron uptake. These findings demonstrate that NDV exacerbated ferroptosis in tumor cells by inducing YAP degradation. Our study provides new insights into the mechanism of NDV-induced ferroptosis and highlights the critical role that oncolytic viruses play in the treatment of drug-resistant cancers.IMPORTANCEThe oncolytic Newcastle disease virus (NDV) is being developed for use in cancer treatment; however, its oncolytic mechanism is still not completely understood. The Hippo pathway, which is a tumor suppressor pathway, is frequently dysregulated in tumor tissues due to aberrant yes-associated protein 1 (YAP) activation. In this study, we have demonstrated that NDV degrades YAP to induce ferroptosis and promote virus replication in tumor cells. Notably, NDV was found to induce ubiquitin-mediated degradation of YAP at Lys90 through E3 ubiquitin ligase parkin (PRKN). Our study reveals a new mechanism by which NDV induces ferroptosis and provides new insights into NDV as an oncolytic agent for cancer treatment.

Plant dehydrins and dehydrin-like proteins: characterization and participation in abiotic stress response

Abiotic stress has a significant impact on plant growth and development. It causes changes in the subcellular organelles, which, due to their stress sensitivity, can be affected. Cellular components involved in the abiotic stress response include dehydrins, widely distributed proteins forming a class II of late embryogenesis abundant protein family with characteristic properties including the presence of evolutionarily conserved sequence motifs (including lysine-rich K-segment, N-terminal Y-segment, and often phosphorylated S motif) and high hydrophilicity and disordered structure in the unbound state. Selected dehydrins and few poorly characterized dehydrin-like proteins participate in cellular stress acclimation and are also shown to interact with organelles. Through their functioning in stabilizing biological membranes and binding reactive oxygen species, dehydrins and dehydrin-like proteins contribute to the protection of fragile organellar structures under adverse conditions. Our review characterizes the participation of plant dehydrins and dehydrin-like proteins (including some organellar proteins) in plant acclimation to diverse abiotic stress conditions and summarizes recent updates on their structure (the identification of dehydrin less conserved motifs), classification (new proposed subclasses), tissue- and developmentally specific accumulation, and key cellular activities (including organellar protection under stress acclimation). Recent findings on the subcellular localization (with emphasis on the mitochondria and plastids) and prospective applications of dehydrins and dehydrin-like proteins in functional studies to alleviate the harmful stress consequences by means of plant genetic engineering and a genome editing strategy are also discussed.

Integrative Omics Analysis of Three Oil Palm Varieties Reveals (Tanzania × Ekona) TE as a Cold-Resistant Variety in Response to Low-Temperature Stress

Oil palm (Elaeis guineensis Jacq.) is an economically important tropical oil crop widely cultivated in tropical zones worldwide. Being a tropical crop, low-temperature stress adversely affects the oil palm. However, integrative leaf transcriptomic and proteomic analyses have not yet been conducted on an oil palm crop under cold stress. In this study, integrative omics transcriptomic and iTRAQ-based proteomic approaches were employed for three oil palm varieties, i.e., B × E (Bamenda × Ekona), O × G (E. oleifera × Elaeis guineensis), and T × E (Tanzania × Ekona), in response to low-temperature stress. In response to low-temperature stress at (8 °C) for 5 days, a total of 5175 up- and 2941 downregulated DEGs in BE-0_VS_BE-5, and a total of 3468 up- and 2443 downregulated DEGs for OG-0_VS_OG-5, and 3667 up- and 2151 downregulated DEGs for TE-0_VS_TE-5 were identified. iTRAQ-based proteomic analysis showed 349 up- and 657 downregulated DEPs for BE-0_VS_BE-5, 372 up- and 264 downregulated DEPs for OG-0_VS_OG-5, and 500 up- and 321 downregulated DEPs for TE-0_VS_TE-5 compared to control samples treated at 28 °C and 8 °C, respectively. The KEGG pathway correlation of oil palm has shown that the metabolic synthesis and biosynthesis of secondary metabolites pathways were significantly enriched in the transcriptome and proteome of the oil palm varieties. The correlation expression pattern revealed that TE-0_VS_TE-5 is highly expressed and BE-0_VS_BE-5 is suppressed in both the transcriptome and proteome in response to low temperature. Furthermore, numerous transcription factors (TFs) were found that may regulate cold acclimation in three oil palm varieties at low temperatures. Moreover, this study identified proteins involved in stresses (abiotic, biotic, oxidative, and heat shock), photosynthesis, and respiration in iTRAQ-based proteomic analysis of three oil palm varieties. The increased abundance of stress-responsive proteins and decreased abundance of photosynthesis-related proteins suggest that the TE variety may become cold-resistant in response to low-temperature stress. This study may provide a basis for understanding the molecular mechanism for the adaptation of oil palm varieties in response to low-temperature stress in China.

Effects of Different Nitrogen Forms and Exogenous Application of Putrescine on Heat Stress of Cauliflower: Photosynthetic Gas Exchange, Mineral Concentration and Lipid Peroxidation

This study examines the effect of the exogenous application of polyamine putrescine together with the application of different ratios of nitrate/ammonium (NO₃⁻/NH₄⁺), on the physiology of cauliflower subjected to heat stress. The 50:50 NO₃⁻/NH₄⁺ ratio was the best ratio against heat stress. As a result of the joint application of these compounds, a higher photosynthetic rate, a higher accumulation of both photosynthesis-related compounds and pigments, total proteins, and a change in the status of nutrients were obtained. Particularly, the decrease in content of calcium, chloride and sulphate in plants under heat stress is ameliorated by the ammonium effect. Additionally, it is important to highlight that cauliflower waste contains a higher content of mineral nutrients than floret cauliflower. These effects were more marked in young leaves. Furthermore, a synergistic effect for coping with heat stress between the polyamine and the nutritional treatment was observed. For this, both the application of putrescine and the feeding of plants with a 50:50 NO₃⁻/NH₄⁺ ratio before heat stress is proposed for the first time as an agricultural practice for increasing the thermotolerance of cauliflower cv Moonshine. On the other hand, due to the lower lipid peroxidation rate obtained in cauliflower leaves, these plants could be used for health purposes as ointments or other nutraceutical products, making the cultivation of this kind of cruciferous more sustainable.

Proteomics: a powerful tool to study plant responses to biotic stress

In recent years, mass spectrometry-based proteomics has provided scientists with the tremendous capability to study plants more precisely than previously possible. Currently, proteomics has been transformed from an isolated field into a comprehensive tool for biological research that can be used to explain biological functions. Several studies have successfully used the power of proteomics as a discovery tool to uncover plant resistance mechanisms. There is growing evidence that indicates that the spatial proteome and post-translational modifications (PTMs) of proteins directly participate in the plant immune response. Therefore, understanding the subcellular localization and PTMs of proteins is crucial for a comprehensive understanding of plant responses to biotic stress. In this review, we discuss current approaches to plant proteomics that use mass spectrometry, with particular emphasis on the application of spatial proteomics and PTMs. The purpose of this paper is to investigate the current status of the field, discuss recent research challenges, and encourage the application of proteomics techniques to further research.