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OJIP chlorophyll a fluorescence is widely used for the rapid assessment of photosynthetic performance, but field workflows may alter the physiological state of the plants probed before the saturating pulse. We compared eight dark-acclimation and sample-handling workflows in field-grown Sida hermaphrodita and Miscanthus × giganteus: daytime clip acclimation, evening and night measurements with or without clip acclimation, flashlight-assisted night measurements, and detached-shoot measurements after laboratory green-light exposure. The same marked leaves were measured sequentially, and the analysis focused on primary OJIP fluorescence levels, phase-specific O-J, J-I and I-P kinetics, area above the transient, FV/FM and FK/FJ. Workflow choice altered OJIP trajectories in both species. Evening and night workflows generally increased the area above the transient relative to the Day-clip method, indicating that short daytime clip acclimation and prolonged natural darkness did not produce equivalent reference states. Night-flashlight and Detached-green workflows introduced further deviations, including altered FO, changed? O-J behavior and I-P rise kinetics. The magnitude and direction of workflow effects were species-specific. These results show that dark-acclimation timing, pre-measurement light exposure and detached-shoot handling are not interchangeable technical details in field OJIP measurements. Workflows should therefore be selected according to the biological question, kept constant within comparisons, and reported with timing, dark-acclimation duration, light exposure and handling conditions.

The biological functions and mechanisms of many cell-type-specific transcriptional cofactors remain unclear. We previously identified Panky (Ankrd33) as a repressive transcriptional co-factor that suppresses Crx-mediated transactivation of photoreceptor genes; however, the biological function of Panky remains unclarified. Here, we investigated the functions of Panky and its paralog, Panky-like (Ankrd33b), in mice of either sex. Single knockout (KO) mouse retinas of Panky or Panky-like did not show significant alterations at both histological and functional levels compared to those of control mice. We then established and examined Panky and Panky-like double knockout (PPL DKO) mice. PPL DKO mice exhibited decreased light-evoked activities detected by electroretinogram (ERG), impaired cone photoreceptor morphology revealed by immunohistochemistry, and structural deformity of cone outer segments and synaptic terminals indicated by transmission electron microscopy (TEM), followed by cone death at a later stage. Lipidomics analysis revealed elevated ganglioside levels in PPL DKO retinas, consistent with the increased immunoreactivity of GT1b and GD3 in the outer segment layer. RNA-seq analysis was conducted in a cone-enriched context resulting from Nrl deficiency and showed that the Cerkl gene, whose mutations in humans cause retinitis pigmentosa (RP26), was upregulated in Panky/Panky-like/Nrl triple KO mice. Transcriptional assays showed that PPL suppressed Crx-mediated transactivation of Cerkl In addition, AAV-mediated Cerkl overexpression in the mouse retina induced significant photoreceptor cell death. Taken together, these findings suggest that the repressive Panky and Panky-like co-factors, which modulate Crx transcriptional activities and thus ganglioside levels in the mouse retina, are essential for cone photoreceptor structure and maintenance.Significance statement The retina is a light-sensing neural tissue in the eye. Photoreceptor cells (PRs) in the retina receive light stimuli. Rod PRs mediate dim-light vision, whereas cone PRs are responsible for bright and color vision. The present study identified that Panky and Panky-like genes are predominantly expressed in PRs in the mouse retina. Panky and Panky-like double-knockout mice exhibit impaired cone cell morphology, cone cell death, and visual dysfunction. In addition, gangliosides, which are chemically bonded lipids and sugars essential for cell membrane stability and function, accumulate in the photoreceptor layer. This study showed that Panky and Panky-like genes regulate ganglioside levels in the retina and play essential roles in the structure and maintenance of cone photoreceptor cells.

This article reviews how histone acetyltransferases (HATs) regulate plant responses to salt, drought, temperature, and light/UV-B stresses through histone and non-histone acetylation. Abiotic stresses, including drought, salinity, temperature extremes, and light stress, severely constrain plant growth and crop productivity. Histone acetyltransferases (HATs) are important epigenetic regulators that connect environmental signals with chromatin remodeling and stress-responsive gene expression. In this review, we summarize the classification and structural features of major plant HAT families, including GCN5-related N-acetyltransferase (GNAT), MOZ, YBF2/SAS3, SAS2, and TIP60 (MYST), TATA-binding protein-associated factor II 250 (TAFII250), and E1A-binding protein p300/cAMP-response element-binding protein (p300/CBP)-related proteins, and discuss how their substrate specificity is influenced by catalytic domains, interacting proteins, chromatin context, and subcellular localization. We then synthesize current evidence for the roles of HATs in plant responses to salt, drought, temperature, and light stresses, with emphasis on their functions in histone acetylation, non-histone acetylation, transcription factor recruitment, and physiological stress adaptation. We further discuss conserved and species-specific mechanisms, context-dependent regulatory patterns, and crosstalk between HATs and other epigenetic or metabolic pathways. Finally, we highlight unresolved questions regarding substrate selection, spatiotemporal regulation, non-model species, and multi-stress responses. This review provides an integrated framework for understanding HAT-mediated stress regulation and offers perspectives for improving crop stress resilience through epigenetic approaches.

The tumour microenvironment comprising tumour cells, immune infiltrates, stromal components, and the extracellular matrix (ECM) plays a central role in cancer biology, modulating key hallmarks, such as proliferation, immune evasion, and metastasis. The ECM is a dynamic network of collagens, elastin, glycoproteins, and proteoglycans and emerging evidence highlights its role in tumour progression, with loss of matrix organisation altering tumour cell behaviour through both pro- and anti-tumourigenic mechanisms. Uveal melanoma (UM), the most common primary intraocular malignancy in adults, carries a poor prognosis due to its propensity for hepatic metastasis and limited therapeutic options. The uveal tract, comprising the choroid, ciliary body, and iris, relies on highly specialised ECM architectures, and we describe in this review how they support nutrient exchange, lens accommodation, and light regulation while mediating essential biochemical and biomechanical signalling. Understanding this baseline ECM is essential for interpreting the pathological matrix remodelling that occurs in UM. We describe marked compositional differences in ECM between low- and high-metastatic risk primary UM, revealing key mechanisms of tumour progression, including upregulation of structural collagens, fibronectin, laminins, and ECM-remodelling enzymes that activate oncogenic signalling pathways enhancing proliferation, invasion, and metastatic competence. We also explore the hepatic metastatic niche, where stellate cell-driven ECM remodelling promotes a fibrotic, immune-restrictive microenvironment that limits therapeutic efficacy. Finally, we discuss experimental constraints limiting ECM research and highlight advances in decellularised scaffolds, three-dimensional culture systems, and multi-omics technologies to dissect tumour-matrix interactions and uncover ECM-targeted therapeutic vulnerabilities with the potential to improve UM's poor clinical outcomes.

Rheum officinale Baill., a foundational plant in traditional Chinese medicine, whose roots and rhizomes exhibit significant pharmacological activities primarily attributed to anthraquinones and other bioactive compounds. However, the transcriptional regulatory mechanisms underlying anthraquinone biosynthesis are not well understood, and the key regulatory factors require further investigation. MYB transcription factors play central roles in secondary metabolism and stress signaling, suggesting their potential involvement in anthraquinone regulation, particularly in response to environmental cues such as UV-B radiation and hormonal signals like methyl jasmonate (MeJA). We performed a genome-wide identification of MYB genes in R. officinale, identifying 237 RoMYBs, including 150 R2R3-MYBs, 81 R1-MYBs, four 3R-MYBs, and two atypical members. Phylogenetic, structural, and evolutionary analyses revealed conserved subfamily organization and gene family expansion driven primarily by segmental duplication. Notably, UV-B treatment significantly induced the accumulation of several anthraquinones, including rhein and emodin, in a time-dependent manner. Expression profiling identified RoMYBs responsive to both MeJA and UV-B, with RoMYB128 and RoMYB134 showing consistent upregulation that correlated with anthraquinone accumulation. Co-expression analysis further revealed that these two genes strongly correlated with multiple CHS-related structural genes in the anthraquinone biosynthetic pathway. Subcellular localization analysis confirmed nuclear localization of both proteins, and transcriptional activity assays revealed that RoMYB128 functions as a transcriptional activator. This study provides the first comprehensive genomic overview of the MYB family in R. officinale and highlights candidate regulators that integrate light and hormone signaling to modulate anthraquinone biosynthesis, thereby offering a foundation for future mechanistic studies and metabolic engineering efforts.

This study combines remote sensing, geochemical data, mineralogical analyses, and field investigations to examine the hydrothermal origin of the Banded Iron Formations (BIFs) in the Fatira region of the Egyptian Nubian Shield. The BIFs are situated within sheared metavolcanic sheeted dykes that form part of the ophiolitic mélange belt. These rocks show varying degrees of shearing due to the Fatira Shear Zone, which mainly consists of protomylonite, mylonite, and ultramylonite. The area is included in the Barud Gneissic Complex, along the ENE-trending dextral shear zone of the Qena-Safaga Line. The protolith underwent crustal shortening, leading to dextral movement along the Fatira Shear Zone. A study utilizing Landsat-8 imagery and the SAM method applied to ASTER data identified iron oxides, along with zones of chlorite and CO3-OH-bearing minerals, in the study area. The SAM algorithm mapped the distribution of common iron minerals, showing moderate to high lineament density and metavolcanic composition. The BIFs appear as thick single bands (3-4 m) along the outer edges of the shear zone and as thinner multiple bands within its central part. Field observations and mineralogical analyses indicate that the single bands consist of martitized magnetite-silicate facies, suggesting they are relatively unaltered. In contrast, the multiple bands comprise magnetite-chert-jasper facies, indicating significant alteration. Geochemical analyses support a hydrothermal genesis for the BIFs, with shearing planes acting as pathways for fluid flow. It is inferred that the protoliths of the BIFs originate from the host sheared metavolcanic sheeted dykes, which were affected by hydrothermal solutions. This research highlights the importance of integrating fieldwork, remote sensing, and laboratory analyses to understand better the formation and distribution of BIFs in tectonically active regions. The findings shed light on hydrothermal-related BIF formation within the sheared metavolcanic setting of the Wadi Fatira area and provide a useful framework for understanding iron mineralization in similar tectonically controlled environments.

Monolithic photo-rechargeable batteries (PRB) are attractive solution for powering off-grid autonomous systems. However, the fundamental effects limiting the light-charging process in such devices are not well understood. Herein, we present an integrated PRB design that can be fully charged under a range of illuminances. We use it as a model system to correlate the decay in photo-charging current with photo-induced charge kinetics. Our results indicate that light-induced hole transport gradually deteriorates with increasing state of charge, which is attributed to the anion-coupled hole accumulation in the cathode layer. Furthermore, our device reveals that the potential gap between the hole transport layer and the cathode is critical for driving a photo-induced delithiation of the cathode. If the cathode has a more positive delithiation potential than the hole transport level, the photo-charging current rapidly decays despite the photo-cells providing sufficient voltage to charge the battery. These findings demonstrate that the device physics of PRBs vary greatly from that of separately coupled solar cells and batteries, thus providing new insights in their working mechanism and their future design guidelines.

Efficient removal of recalcitrant aromatic compounds in organic wastewater is hindered by ambiguous reaction pathways in conventional single-process polymerization or ring-opening mineralization. Herein, we report a synergistic relay strategy that integrates phenoxyl-radical-mediated oligomerization and aromatic-ring-opening pathways for the highly efficient treatment of organic wastewater. This approach couples an initial high-valence iron-oxo species (HVIO)-driven oligomerization via formal hydrogen atom transfer at one site with a subsequent singlet oxygen (1O2)-mediated ring-opening reaction at an adjacent site, enabled by a dual-single-atom Fe1Cu1/TiO2 photocatalyst. Under solar-light irradiation, photoinduced electrons are transferred to peroxymonosulfate (PMS) at the Fe1 site, which acts as a critical activator to generate HVIO for oligomerization-based removal. Simultaneously, holes oxidize PMS at the Cu1 site to produce 1O2, leading to efficient aromatic-ring-opening. This sequential strategy achieved nearly 72% chemical oxygen demand removal with 23% carbon recovery into separable polymer products within 10 min for the phenol and ultimately reached complete removal with a rate constant of 1.21 min-1, significantly surpassing most reported values. Moreover, the system exhibited excellent stability and long-term activity in a custom-designed photo-filter reactor, highlighting its practical potential. By coupling oligomerization and mineralization, this work provides a groundbreaking and versatile platform for treating complex organic wastewater.