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Ferroptosis is a pervasive non-apoptotic form of cell death highly relevant in various degenerative diseases and malignancies. The hallmark of ferroptosis is uncontrolled and overwhelming peroxidation of polyunsaturated fatty acids contained in membrane phospholipids, which eventually leads to rupture of the plasma membrane. Ferroptosis is unique in that it is essentially a spontaneous, uncatalyzed chemical process based on perturbed iron and redox homeostasis contributing to the cell death process, but that it is nonetheless modulated by many metabolic nodes that impinge on the cells susceptibility to ferroptosis. Among the various nodes affecting ferroptosis sensitivity, several have emerged as promising candidates for pharmacological intervention, rendering ferroptosis-related proteins attractive targets for the treatment of numerous currently incurable diseases. Herein, the current members of a Germany-wide research consortium focusing on ferroptosis research, as well as key external experts in ferroptosis who have made seminal contributions to this rapidly growing and exciting field of research, have gathered to provide a comprehensive, state-of-the-art review on ferroptosis. Specific topics include: basic mechanisms, in vivo relevance, specialized methodologies, chemical and pharmacological tools, and the potential contribution of ferroptosis to disease etiopathology and progression. We hope that this article will not only provide established scientists and newcomers to the field with an overview of the multiple facets of ferroptosis, but also encourage additional efforts to characterize further molecular pathways modulating ferroptosis, with the ultimate goal to develop novel pharmacotherapies to tackle the various diseases associated with - or caused by - ferroptosis.

This review summarizes recent progress in our current understanding of the mechanisms underlying the cell death pathways in bryophytes, focusing on conserved pathways and particularities in comparison to angiosperms. Regulated cell death (RCD) plays key roles during essential processes along the plant life cycle. It is part of specific developmental programmes and maintains homeostasis of the organism in response to unfavourable environments. Bryophytes could provide valuable models to study developmental RCD processes as well as those triggered by biotic and abiotic stresses. Some pathways analogous to those present in angiosperms occur in the gametophytic haploid generation of bryophytes, allowing direct genetic studies. In this review, we focus on such RCD programmes, identifying core conserved mechanisms and raising new key questions to analyse RCD from an evolutionary perspective. [ABSTRACT FROM AUTHOR]

Plants face the most diverse climatic conditions throughout their life cycle. As sessile organisms, they are remarkably resilient to adverse environments, which have been exacerbated in the current context of global change. The way in which plants sense and respond to various types of abiotic stresses varies depending on the severity of the stress and the developmental stage of the plant, affecting both vegetative and reproductive aspects. Understanding how plants respond and adapt to a changing environment is crucial for predicting and mitigating the impacts of climate change on ecosystems and ensuring the future survival and reproduction of plant species. [ABSTRACT FROM AUTHOR]

The female gametophyte of flowering plants, called the embryo sac, develops from a haploid cell named the functional megaspore, which is specified after meiosis by the diploid sporophyte. In Arabidopsis, the functional megaspore undergoes three syncitial mitotic divisions followed by cellularization to form seven cells of four cell types including two female gametes. The plant hormone auxin is important for sporophytic developmental processes, and auxin levels are known to be regulated by biosynthesis and transport. Here, we investigated the role of auxin biosynthetic genes and auxin influx carriers in embryo sac development. We find that genes from the YUCCA/TAA pathway (YUC1, YUC2, YUC8, TAA1, TAR2) are expressed asymmetrically in the developing ovule and embryo sac from the two-nuclear syncitial stage until cellularization. Mutants for YUC1 and YUC2 exhibited defects in cell specification, whereas mutations in YUC8, as well as mutations in TAA1 and TAR2, caused defects in nuclear proliferation, vacuole formation and anisotropic growth of the embryo sac. Additionally, expression of the auxin influx carriers AUX1 and LAX1 were observed at the micropylar pole of the embryo sac and in the adjacent cells of the ovule, and the aux1 lax1 lax2 triple mutant shows multiple gametophyte defects. These results indicate that both localized auxin biosynthesis and auxin import, are required for mitotic divisions, cell expansion and patterning during embryo sac development.

Sensing and response to high temperatures are crucial to prevent heat‐related damage and to preserve cellular and metabolic functions. The response to heat stress is a complex and coordinated process that involves several subcellular compartments and multi‐level regulatory networks that are synchronized to avoid cell damage while maintaining cellular homeostasis. In this review, we provide an insight into the most recent advances in elucidating the molecular mechanisms involved in heat stress sensing and response in Marchantia polymorpha. Based on the signaling pathways and genes that were identified in Marchantia, our analyses indicate that although with specific particularities, the core components of the heat stress response seem conserved in bryophytes and angiosperms. Liverworts not only constitute a powerful tool to study heat stress response and signaling pathways during plant evolution, but also provide key and simple mechanisms to cope with extreme temperatures. Given the increasing prevalence of high temperatures around the world as a result of global warming, this knowledge provides a new set of molecular tools with potential agronomical applications. Sensing and response to high temperatures are crucial mechanisms to prevent heat‐related damage and to preserve cellular functions. In this review we aim to provide an insight into the most recent advances in elucidating the mechanisms and pathways involved in the response to heat stress in the bryophyte Marchantia polymorpha. We discuss conserved and divergent pathways that relate temperature sensing with a plethora of transduction cascades that are emerging as central future research directions. [ABSTRACT FROM AUTHOR]

Regulated cell death plays key roles during essential processes throughout the plant life cycle. It takes part in specific developmental programs and maintains homeostasis of the organism in response to unfavorable environments. Ferroptosis is a recently discovered iron-dependent cell death pathway characterized by the accumulation of lipid reactive oxygen species. In plants, ferroptosis shares all the main hallmarks described in other systems. Those specific features include biochemical and morphological signatures that seem to be conserved among species. However, plant cells have specific metabolic pathways and a high degree of metabolic compartmentalization. Together with their particular morphology, these features add more complexity to the plant ferroptosis pathway. In this review, we summarize the most recent advances in elucidating the roles of ferroptosis in plants, focusing on specific triggers, the main players, and underlying pathways. [ABSTRACT FROM AUTHOR]

Nitric Oxide (NO) is a small highly diffusible gas and a ubiquitous bioactive molecule. Recent advances in the mechanisms by which NO modulates molecular and physiological plant responses are discussed with an aim to integrate the NO biochemistry in plant biology processes.

Mitochondrial Nicotinamide adenine dinucleotide (NADH) dehydrogenase complex is the first complex of the mitochondrial electron transfer chain. In plants and in a variety of eukaryotes except Opisthokonta, complex I (CI) contains an extra spherical domain called carbonic anhydrase (CA) domain. This domain is thought to be composed of trimers of gamma type CA and CA-like subunits. In Arabidopsis, the CA gene family contains five members (CA1, CA2, CA3, CAL1 and CAL2). The CA domain appears to be crucial for CI assembly and is essential for normal embryogenesis. As CA and CA-like proteins are arranged in trimers to form the CA domain, it is possible for the complex to adopt different arrangements that might be tissue-specific or have specialized functions. In this work, we show that the proportion of specific CI changes in a tissue-specific manner. In immature seeds, CI assembly may be indistinctly dependent on CA1, CA2 or CA3. However, in adult plant tissues (or tissues derived from stem cells, as cell cultures), CA2-dependent CI is clearly the most abundant. This difference might account for specific physiological functions. We present evidence suggesting that CA3 does not interact with any other CA family member. As CA3 was found to interact with CI FRO1 (NDUFS4) subunit, which is located in the matrix arm, this suggests a role for CA3 in assembly and stability of CI. [ABSTRACT FROM AUTHOR]

Main conclusion: AtPLC2 is an essential gene in Arabidopsis, since it is required for female gametogenesis and embryo development. AtPLC2 might play a role in cell division during embryo-sac development and early embryogenesis. Phosphoinositide-specific phospholipase C (PI-PLC) plays an important role in signal transduction during plant development and in the response to various biotic- and abiotic stresses. The Arabidopsis PI- PLC gene family is composed of nine members, named PLC1 to PLC9. Here, we report that PLC2 is involved in female gametophyte development and early embryogenesis. Using two Arabidopsis allelic T-DNA insertion lines with different phenotypic penetrations, we observed both female gametophytic defects and aberrant embryos. For the plc2- 1 mutant (Ws background), no homozygous plants could be recovered in the offspring from self-pollinated plants. Nonetheless, plc2- 1 hemizygous mutants are affected in female gametogenesis, showing embryo sacs arrested at early developmental stages. Allelic hemizygous plc2- 2 mutant plants (Col-0 background) present reduced seed set and embryos arrested at the pre-globular stage with abnormal patterns of cell division. A low proportion (0.8%) of plc2- 2 homozygous mutants was found to escape lethality and showed morphological defects and disrupted megagametogenesis. PLC2-promoter activity was observed during early megagametogenesis, and after fertilization in the embryo proper. Immunolocalization studies in early stage embryos revealed that PLC2 is restricted to the plasma membrane. Altogether, these results establish a role for PLC2 in both reproductive- and embryo development, presumably by controlling mitosis and/or the formation of cell-division planes. [ABSTRACT FROM AUTHOR]