Ferroptosis is a newly discovered form of regulated cellular demise, characterized by the accumulation of intracellular oxidative stress that is dependent on iron. Ferroptosis plays a crucial role not only in the development and treatment of tumors but also in the pathogenesis of neurodegenerative diseases and illnesses related to ischemia-reperfusion injury. This mode of cell death possesses distinctive properties that differentiate it from other forms of cell death, including unique morphological changes at both the cellular and subcellular levels, as well as molecular features that can be detected using specific methods. The use of fluorescent probes has become an invaluable means of detecting ferroptosis, owing to their high sensitivity, real-time in situ monitoring capabilities, and minimal damage to biological samples. This review comprehensively elucidates the physiological mechanisms underlying ferroptosis, while also detailing the development of fluorescent probes capable of detecting ferroptosis-related active species across various cellular compartments, including organelles, the nucleus, and the cell membrane. Additionally, the review explores how the dynamic changes and location of active species from different cellular compartments can influence the ignition and execution of ferroptotic cell death. Finally, we discuss the future challenges and opportunities for imaging ferroptosis. We believe that this review will not only aid in the elucidation of ferroptosis\'s physiological mechanisms but also facilitate the identification of novel treatment targets and means of accurately diagnosing and treating ferroptosis-related diseases.

Recently accumulated evidence has indicated that the nucleomembrane shuttling of cellular proteins is common, which provides new insight into the subcellular translocation and biological functions of proteins synthesized in the cytoplasm. The present study aimed to clarify the trafficking of proteins between the plasma membrane and nucleus. These proteins primarily consist of transmembrane receptors, membrane adaptor proteins, adhesive proteins, signal proteins and nuclear proteins, which contribute to proliferation, apoptosis, chemoresistance, adhesion, migration and gene expression. The proteins frequently undergo cross‑talk, such as the interaction of transmembrane proteins with signal proteins. The transmembrane proteins undergo endocytosis, infusion into organelles or proteolysis into soluble forms for import into the nucleus, while nuclear proteins interact with membrane proteins or act as receptors. The nucleocytosolic translocation involves export or import through nuclear membrane pores by importin or exportin. Nuclear proteins generally interact with other transcription factors, and then binding to the promoter for gene expression, while membrane proteins are responsible for signal initiation by binding to other membrane and/or adaptor proteins. Protein translocation occurs in a cell‑specific manner and is closely linked to cellular biological events. The present review aimed to improve understanding of cytosolic protein shuttling between the plasma membrane and nucleus and the associated signaling pathways.

For decades, the biological roles of plant lectins remained obscure and subject to speculation. With the advent of technological and scientific progress, researchers have compiled a vast amount of information regarding the structure, biological activities and functionality of hundreds of plant lectins. Data mining of genomes and transcriptome sequencing and high-throughput analyses have resulted in new insights. This review aims to provide an overview of what is presently known about plant lectins, highlighting their versatility and the importance of plant lectins for a multitude of biological processes, such as plant development, immunity, stress signaling and regulation of gene expression. Though lectins primarily act as readers of the glycocode, the multiple roles of plant lectins suggest that their functionality goes beyond carbohydrate-recognition.

Mitochondria are controlled by the coordination of two genomes: the mitochondrial and the nuclear DNA. As such, variations in nuclear gene expression as a consequence of mutations and epigenetic modifications can affect mitochondrial functionality. Conversely, the opposite could also be true. However, the relationship between mitochondrial dysfunction and epigenetics, such as nuclear DNA methylation, remains largely unexplored. Mitochondria function as central metabolic hubs controlling some of the main substrates involved in nuclear DNA methylation, via the one carbon metabolism, the tricarboxylic acid cycle and the methionine pathway. Here, we review key findings and highlight new areas of focus, with the ultimate goal of getting one step closer to understanding the genomic effects of mitochondrial dysfunction on nuclear epigenetic landscapes.

TA characteristic feature of amyloid structures is polymorphism. The study of amyloid structures and their formation process was carried out for synthetic and recombinant Ab(1-40) and Ab(1-42) peptide preparations. In the study of these peptides, we recognized fibrils of different morphologies. We observed fibrillar formations in the form of single fibrils, ribbons, bundles, bunches, and clusters. Polymorphism of fibrils was observed not only when the environmental conditions changed, but under the same conditions and this was a common characteristics of all amyloid formations. Fibrils of Ab(1-40) peptides tended to form aggregates of fibrils in the form of ribbons, while Ab(1-42) peptide under the same conditions polymerized in the form of rough fibrils of different diameters and tends to branch. We assume that the formation of fibrils of Ab(1-40) and Ab(1-42) peptides occurs according to a simplified scheme: a destabilized monomer ® a ring oligomer ® a mature fibril consisting of ring oligomers. Proceeding from the proposition that the ring oligomer is the main building block of amyloid fibril (similar to the cell in the body), it is easy to explain fibril polymorphism, as well as fragmentation of mature fibrils under various external influences, branching and irregularity of diameter (surface roughness) of fibrils. One aspect of the study of amyloidogenesis is the determination of the regions of the protein chain forming the core of the amyloid fibril. We theoretically predicted amyloidogenic regions for two isoforms of Ab peptides capable of forming an amyloid structure: 16-21 and 32-36 residues. Using the method of tandem mass spectrometry, these regions were determined experimentally. It was shown that the regions of Ab(1-40) peptide from 16 to 22 and from 28 to 40 residues were resistant to the action of proteases, i.e. its formed the core of the amyloid fibril. For Ab(1-42) peptide the whole sequence is not available for the action of proteases, which indicates a different way of associating ring oligomers in the formation of fibrils. Based on electron microscopy and mass spectrometry data we proposed a molecular model of the fibril formed by Ab(1-40) and Ab(1-42) peptides.
Kharakternoĭ osobennost\'iu amiloidnykh struktur iavliaetsia polimorfizm. Izuchenie amiloidnykh struktur i protsessa ikh formirovaniia bylo provedeno dlia sinteticheskikh i rekombinantnykh preparatov Ab(1-40) i Ab(1-42) peptidov. Pri issledovanii étikh peptidov nami byli polucheny fibrilly raznoĭ morfologii. My nabliudali fibrilliarnye obrazovaniia v vide odinochnykh fibrill, lent, zhgutov, puchkov i klasterov. Polimorfizm fibrill nabliudaetsia ne tol\'ko pri izmenenii usloviĭ sredy, no i v odnikh i tekh zhe usloviiakh, i iavliaetsia obshcheĭ kharakternoĭ osobennost\'iu vsekh amiloidnykh formirovaniĭ. Fibrilly Ab(1-40) peptidov imeiut tendentsiiu formirovat\' agregaty fibrill v vide lent, v to vremia kak Ab(1-42) peptid v tekh zhe usloviiakh polimerizuetsia v vide sherokhovatykh fibrill raznogo diametra i imeet sklonnost\' k vetvleniiu. My predpolagaem, chto formirovanie fibrill Ab(1-40) i Ab(1-42) peptidov proiskhodit po uproshchennoĭ skheme: destabilizirovannyĭ monomer ® kol\'tsevoĭ oligomer ® zrelaia fibrilla, sostoiashchaia iz kol\'tsevykh oligomerov. Iskhodia iz polozheniia, chto imenno kol\'tsevoĭ oligomer iavliaetsia osnovnoĭ stroitel\'noĭ edinitseĭ amiloidnoĭ fibrilly (analogichno kletke v organizme), mozhno legko ob\"iasnit\' polimorfizm fibrill, a takzhe droblenie zrelykh fibrill pri razlichnykh vneshnikh vozdeĭstviiakh, vetvlenie i neodnorodnost\' diametra (sherokhovatost\' poverkhnosti) fibrill. Odnim iz aspektov izucheniia amiloidogeneza iavliaetsia opredelenie uchastkov polipeptidnoĭ tsepi, formiruiushchikh ostov amiloidnoĭ fibrilly. Nami teoreticheski predskazany amiloidogennye uchastki dlia dvukh izoform Ab peptidov, sposobnye formirovat\' amiloidnuiu strukturu – aminokislotnye ostatki (a.o) 16-21 i 32-36. Pri pomoshchi metoda tandemnoĭ mass-spektrometrii éti uchastki byli opredeleny éksperimental\'no. Pokazano, chto uchastki peptida Ab(1-40) s 16 po 22 i s 28 po 40 a.o. ustoĭchivy k vozdeĭstviiu proteaz, to est\' vkhodiat v ostov amiloidnoĭ fibrilly. Dlia Ab(1-42) peptida pokazano, chto vsia posledovatel\'nost\' nedostupna deĭstviiu proteaz, chto svidetel\'stvuet o raznom sposobe assotsiatsii kol\'tsevykh oligomerov pri formirovanii fibrill. Na osnovanii metodov élektronnoĭ mikroskopii i mass-spektrometricheskikh dannykh nami predlozhena molekuliarnaia model\' fibrilly, obrazovannoĭ Ab(1-40) i Ab(1-42) peptidami.

Primary melanosis of the dentate nucleus is a rarely described entity with neither known cause nor definitive clinicopathologic correlation. We revisit this previously reported phenomenon by presenting one such case with a review of the pathology as well as additional investigations including elemental analysis by energy-dispersive X-ray, immunohistochemistry and electron microscopy. The lesion presented macroscopically as a sharply defined, black pigmentation that was restricted to the dentate nucleus of the cerebellum. Other deep nuclei were uninvolved. Similarly, other areas of the cerebellum, brainstem, and supratentorial regions were macroscopically free of pigment. Microscopically, however, the pigment was noted to be present, albeit in microscopic deposits, within layers of the cerebellar cortex. Additionally, immunohistochemistry and electron microscopy defined an intracellular component within astrocytes. X-ray analysis of the pigment showed it to consist almost entirely of sulfur, an element known to be prominent in neuromelanin. This report also describes an association of the pigment with astrocytes by ultrastructural examination. We discuss the results of our findings in the context of etiopathogenetic considerations, seeking to gain a better understanding of this abnormal pigmentation and its relationship to neuromelanin.

Acid soils with elevated levels of soluble aluminium (Al) comprise ~40% of the world\'s arable land, but there remains much uncertainty regarding the mechanisms by which Al is rhizotoxic. This review examines the kinetics of the toxic effects of Al on the root elongation rate (RER), its effects on root tissues, and its location at a subcellular level. Depending upon the concentration and plant species, soluble Al decreases the RER in a median time of 73min, but in as little as 5min in soybean. This is initially due to a decreased rate at which cells expand anisotropically in the elongation zone. Thereafter, rhizodermal and outer cortical cells rupture through decreased cell wall relaxation. It is in this region where most Al accumulates in the apoplast. Subsequently, Al impacts root growth at a subcellular level through adverse effects on the plasma membrane (PM), cytoplasm, and nucleus. At the PM, Al alters permeability, fluidity, and integrity in as little as 0.5h, whilst it also depolarizes the PM and reduces H(+)-ATPase activity. The Al potentially crosses the PM within 0.5h where it is able to bind to the nucleus and inhibit cell division; sequestration within the vacuole is required to reduce the toxic effects of Al within the cytoplasm. This review demonstrates the increasing evidence of the importance of the initial Al-induced inhibition of wall loosening, but there is evidence also of the deleterious effects of Al on other cellular processes which are important for long-term root growth and function.

Retrograde signaling, defined as the signaling events leading from the plastids to the nucleus, coordinates the expression of plastid and nuclear genes and is crucial for metabolic as well as developmental processes of the plastids. In the recent past, the identification of various components that are involved in the generation and transmission of plastid-originated retrograde signals and the regulation of nuclear gene expression has only provided a glimpse of the plastid retrograde signaling network, which remains poorly understood. The basic assumptions underlying our current understanding of retrograde signaling stayed untouched for many years. Therefore, an attempt has been made in this review article to summarize established facts and recent advances regarding various retrograde signaling pathways derived from different sources, the identification of key elements mediating retrograde signal transduction and also to give an overview of possible signaling molecules that remain to be investigated.