Biology subjects

Zhang, H.

Publications and source records attributed to Zhang, H..

At least 541 records · Page 30Linked to original sources

bioRxiv2024

Profiling of epithelial functional states and fibroblast phenotypes in hormone therapy-naive localised prostate cancer

Localised prostate cancers (PCa) are heterogeneous and multifocal, with diverse outcomes. Current prognostic methods are epithelium-centric, overlooking the complex cellular landscape within the tumour microenvironment (TME), which remains incompletely characterised. We performed a comprehensive analysis of cancerous and adjacent-benign cores from 24 patients with hormone therapy-naive localised PCa using single-cell RNA-sequencing. By integrating copy number variation and transcriptional signatures, we classified epithelial cells across a malignant spectrum, revealing widespread molecular perturbation. We found an expansion of Club cell phenotypes, suggestive of Luminal dedifferentiation. We also performed a detailed annotation of stromal phenotypes, focusing on fibroblasts, and identified a novel peri-neural fibroblast population. Spatial transcriptomics elucidated the precise anatomical distribution of CAFs within the PCa TME. This study provides a valuable foundation for advancing our understanding of PCa pathobiology and developing a comprehensive cellular model of the disease. Statement of SignificanceOur study leverages single-cell RNA-sequencing and spatial transcriptomics to provide a comprehensive cellular annotation of hormone therapy-naive localised PCa. We reveal widespread molecular perturbations in epithelial cells and map distinct fibroblast populations to specific anatomical niches. Notably, we identify a novel peri-neural phenotype associated with nerves, which merits further functional characterisation and exploration as a potential therapeutic target.

cancer biology↗

bioRxiv2024

Foxn3 is part of a transcriptional network that regulates cilia genes in the developing mouse retina

Analysis of retinas from mice with a targeted disruption of the gene encoding the forkhead transcription factor Foxn3 revealed additional displaced amacrine interneurons and retinal astrocytes in the inner plexiform and ganglion cell layers, as well as ectopic primary cilia on bipolar and amacrine interneurons. Foxn3 is a transcriptional repressor and numerous genes linked to cilia structure or assembly were upregulated in embryonic retinas without Foxn3, including Foxj1, a forkhead transcription factor required for motile cilia. CUTCRUN analysis revealed that many of the upregulated retinal genes were bound by the Foxn3 and Rfx3 proteins. A short hydrophobic motif (LXXLXWL) shared by the Foxj1, Foxn4, and Foxn3 proteins was found to be required for association with the Rfx3 protein and for transcriptional repression by Foxn3, as well as for full transcriptional activation by Foxn4 with Rfx3. AlphaFold 3 predicts an interaction between the shared hydrophobic motif and the Rfx3 dimerization domain. Mutations in Rfx3 at the predicted interaction site disrupted association of Rfx3 with Foxn3 or Foxn4. These results reveal a new layer of transcriptional regulation of genes required for cilia, with Foxn3 functioning as a repressor of cilia genes and limiting primary cilia formation in the developing retina.

developmental biology↗

bioRxiv2024

Mutations of schizophrenia risk gene SETD1A dysregulate synaptic function in human neurons

Schizophrenia (SCZ) is a complex neuropsychiatric disorder associated with both common risk variants of small effect sizes and rare risk variants of high penetrance. Rare protein truncating variants (PTVs) in SETD1A (SET Domain Containing 1A) show a strong association with SCZ; however, it remains largely unclear how rare PTVs in SETD1A contribute to the pathophysiology of SCZ. To understand the impact of SETD1A rare PTVs in human neurons, we CRISPR/Cas9-engineered five isogenic pairs of human induced pluripotent stem cells (iPSCs), with a recurrent heterozygous patient-specific PTV mutation c.4582-2delAG in two donor lines and a heterozygous frameshift mutation c.4596_4597insG (p. Leu1533fs) in three donor lines. These two mutations are predicted to cause a premature stop codon in exon 16 of SETD1A, leading to the loss of the conserved SET domain that is critical for its histone methyltransferase activity. We found that these presumably loss-of-function (LoF) mutations caused the SETD1A mRNAs to be degraded by nonsense-mediated decay (NMD), accompanied by a reduction of full-length SETD1A protein level in iPSCs. We then characterized the morphological, electrophysiological, and transcriptomic impacts of the SETD1A+/- LoF mutations in iPSC-derived human excitatory neurons induced by NGN2. We found that the SETD1A+/- exon-16 LoF mutations altered dendrite complexity, dysregulated synaptic transmission, and synaptic plasticity, likely by dysregulating genes involved in synaptic function. These results provide mechanistic insights into how SETD1A+/-exon-16 patient-specific LoF mutations affect neuron phenotypes that may be relevant to the pathophysiology of SCZ.

neuroscience↗

bioRxiv2024

SPLENDID incorporates continuous genetic ancestry in biobank-scale data to improve polygenic risk prediction across diverse populations

Polygenic risk scores are widely used in disease risk stratification, but their accuracy varies across diverse populations. Recent methods large-scale leverage multi-ancestry data to improve accuracy in under-represented populations but require labelling individuals by ancestry for prediction. This poses challenges for practical use, as clinical practices are typically not based on ancestry. We propose SPLENDID, a novel penalized regression framework for diverse biobank-scale data. Our method utilizes ancestry principal component interactions to model genetic ancestry as a continuum within a single prediction model for all ancestries, eliminating the need for discrete labels. In extensive simulations and analyses of 9 traits from the All of Us Research Program (N=224,364) and UK Biobank (N=340,140), SPLENDID significantly outperformed existing methods in prediction accuracy and model sparsity. By directly incorporating continuous genetic ancestry in model training, SPLENDID stands as a valuable tool for robust risk prediction across diverse populations and fairer clinical implementation.

genetics↗

bioRxiv2024

Arginine methylation coordinates with phosphorylation to regulate NADP+ synthesis

NADK is the sole cytosolic enzyme responsible for synthesizing NADP+ from NAD+ within cells. The homeostasis of NAD+/NADP+ is controlled by NADK, usually dysregulated in various cancers, yet the precise underlying regulatory mechanisms remain largely unknown. In this study, we discover that PRMT6 methylates NADK at R39, R41, and R45, resulting in the suppression of NADK kinase activity and NADP+ synthesis. Mutations of these sites promote cancer cell proliferation and tumor growth. PRMT6-mediated methylation of NADK coordinates with Akt-mediated phosphorylation to regulate NADK, which stimulates its activity to increase NADP+ production through relief of an autoinhibitory function inherent to its amino terminus. PRMT6 also inhibits NADK activity in a phosphorylation-independent manner. Furthermore, NADK methylation is upregulated by RB1/E2F pathway in high-fat diet mice. Downregulation of NADK methylation in HCC enhances NADP+ production to promote cancer development. Our findings illuminate the molecular regulatory mechanisms governing NAD+/NADP+ homeostasis, suggesting that the PRMT6-NADK axis emerges as a direct player in high energy state. Furthermore, our research suggests potential therapeutic targets through chemical and genetic interventions. SignificancePrevious studies revealed that phosphorylation of NADK activates its activity in response to nutrient or other signaling pathways. Here, we discovered that PRMT6 methylates NADK at residues R39, R41, and R45, leading to the suppression of NADK kinase activity and NADP+ synthesis. This PRMT6-mediated methylation works in conjunction with Akt-mediated phosphorylation to regulate NADK. Additionally, we found that NADK methylation is upregulated by the RB1/E2F pathway in mice on a high-fat diet. In hepatocellular carcinoma (HCC), the downregulation of NADK methylation enhances NADP+ production, thereby promoting cancer development. Our findings provide a significant breakthrough in understanding the regulation of NADK and its response to environmental factors.

cancer biology↗

bioRxiv2024

Structural Insights into Selective and Dual Antagonism of EP2 and EP4 Prostaglandin Receptors

Prostaglandin E2 (PGE2) signaling through EP2 and EP4 receptors plays a crucial role in inflammation, pain, and cancer progression. Selective and dual antagonists of these receptors have shown promising therapeutic potential. However, the structural basis for their binding modes and selectivity remained unclear. Here, we present cryo-EM structures of human EP2 and EP4 receptors in complex with selective antagonists PF-04418948 and grapiprant, respectively, as well as the dual antagonist TG6-129. These structures reveal distinct binding pockets and interaction networks that govern antagonist selectivity and efficacy. Combining the structural data and functional studies, we uncover the key residues and structural features that differentiate EP2 and EP4 binding sites, including a unique {pi}-{pi} stacking interaction in EP2 and variations in pocket shape and charge distribution. The dual antagonist TG6-129 exhibited a novel binding mode, interacting deeply with EP2 but only shallowly with EP4 in a two-warhead manner. These findings provide a structural framework for understanding prostanoid receptor pharmacology and offer valuable insights for the rational design of improved selective and dual antagonists targeting EP2 and EP4 receptors.

biochemistry↗

bioRxiv2024

D-lactate derived from intestinal bacteria drives lysine D-lactylation to modulate transcription in liver cells

Emerging evidence indicates that the accumulated D-lactate (D-la) from intestinal bacteria induces diverse effects in human intestinal injury diseases. However, its regulatory mechanism and functional consequence remain unclear. Here, we show that the secreted D-la induces lysine D-lactylation (K-Dla) to modulate transcription in host cells. We uncover K-Dla in HepG2 cells stimulated by D-la from E. coli secretions. Then, we confirm the occurrence of D-la-driven K-Dla by four orthogonal approaches. We further validate that the existence of K-Dla in organisms by detecting the mouse liver and human intestinal tissue. Besides, we demonstrate a SCOT1-catalyzed biosynthetic pathway of D-lactyl-CoA, serving as a key donor for K-Dla. Next, we identify the K-Dla landscape with 2895 sites and further suggest the regulation of histone K-Dla in transcription by MNase ChIP-seq and RNA-seq assays. Finally, we show the potential effect of K-Dla on inhibiting the hepatocellular carcinoma cell proliferation. In summary, we report that the secreted D-la can induce K-Dla to regulate transcription, providing a new insight into the function of D-la secreted by gut microbiota and the effect of protein chemical modifications induced by bacterial secretions.

molecular biology↗

bioRxiv2024

A thermoplastic chip for correlative assays combining screening and high-resolution imaging of immune cell responses

Single-cell immune assays are developed for the identification and characterization of individual immune cell responses. Some methods provide snapshots of the phenotype of the cell, such as flow cytometry and single-cell RNA sequencing, whereas others, almost exclusively microscopy-based, can be used for longitudinal studies of individual cells. However, obtaining correlative data on cell dynamics and phenotype of individual immune cells is challenging but can provide more nuanced information of heterogeneous immune cell responses. In this work, we have addressed this challenge by developing an easy-to-use, disposable, thermoplastic microwell chip, designed to support screening and high-resolution imaging of single-cell behavior in two-and three-dimensional cell cultures. We show that the chip has excellent optical properties and we provide simple protocols for efficient long-term cell culture of suspension and adherent cells, the latter grown either as monolayers or as hundreds of single, uniformly-sized spheroids. We demonstrate the applicability of the system for single-cell analysis by correlating the dynamic cytotoxic response of single immune cells grown under different metabolic conditions to their intracellular cytolytic load at the end of the assay. Additionally, we illustrate highly multiplex cytotoxicity screening of tumor spheroids in the chip, comparing the effect of environment cues characteristic of the tumor microenvironment on natural killer (NK) cell-induced killing. Following the functional screening, we perform high-resolution 3D immunofluorescent imaging of infiltrating NK cells within the spheroid volumes.

immunology↗

bioRxiv2024

Prosocial reward relates to speech reception thresholds and age relates to subjective ratings of speech perception in noise

I.Motivation plays an important role in a listeners effort when in noisy environments. However, there remain gaps in the previous literature pertaining to the social psychological factors underlying motivation and listening effort. To fill these gaps, this study explored how prosociality and social reward relate to speech perception in noise (SPiN) in a group of normal hearing English speakers (n = 136; mean age: 29.6, age range: 18-68). We investigated SPiN performance and subjective listening experiences across different speech masking conditions: 1-speaker, 2-speaker, and speech-spectrum shaped noise (SSN), along with a working memory task, and questionnaires pertaining to social orientation. Results indicated a robust effect of different maskers, and that individuals who rated themselves higher in prosocial traits performed better in the masker that yielded the highest threshold out of the three conditions, the 2-speaker condition. Additionally, subjective ratings of listening effort particularly in the 1-speaker condition related to age, where older participants reported greater effort. These findings highlight prosociality and age as important social psychological factors influencing SPiN performance and listening effort, respectively, particularly in complex listening scenarios.

neuroscience↗

bioRxiv2024

SIRT4 enhances the cytotoxicity of NK cells toward hepatic stellate cells and reverses liver fibrosis via AMPKα/P-p53/NKG2DL pathway

Natural killer (NK) cells exhibit antifibrotic properties in liver fibrosis (LF) by suppressing activated hepatic stellate cells (HSCs). SIRT4, a mitochondrial regulatory protein, plays a crucial role as a link between energy metabolism and cell viability. However, the role of SIRT4 in the cytotoxicity of NK cells toward HSCs remains unexplored. In this study, we found that SIRT4 was markedly downregulated in both mouse models and patients with LF. The loss of SIRT4 reduced the cytotoxicity of NK cells against activated HSCs, while its overexpression enhanced this cytotoxicity. Mechanistically, SIRT4 activates AMPK to promote p53 phosphorylation and facilitates its nuclear translocation, which induces the transcription of ULBP1 and ULBP2, members of the NK group 2D Legend (NKG2DL) family of molecules. Finally, overexpression of SIRT4 activated mouse hepatic NK cells and reversed LF by constructing adeno-associated viruses (AAV) that specifically target HSCs. Thus, SIRT4 is essential for the cytotoxicity of NK cells toward HSCs, and AAV8-pGAFP-SIRT4 may serve as a therapeutic approach for managing LF. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/615768v1_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@1e6e987org.highwire.dtl.DTLVardef@edcc2dorg.highwire.dtl.DTLVardef@1f7c2bcorg.highwire.dtl.DTLVardef@111d81d_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2024

Cxcl10 is required for survival during SARS-CoV-2 infection in mice

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the coronavirus disease 2019 (COVID-19) pandemic, remains endemic worldwide [~]5 years since the first documented case. Severe COVID-19 is widely considered to be caused by a dysregulated immune response to SARS-CoV-2 within the respiratory tract. Circulating levels of the chemokine CXCL10 are strongly positively associated with poor outcome; however, its precise role in pathogenesis and its suitability as a therapeutic target have remained undefined. Here, we challenged 4-6 month old C57BL/6 mice genetically deficient in Cxcl10 with a mouse-adapted strain of SARS-CoV-2. Infected male, but not female, Cxcl10-/- mice displayed increased mortality compared to wild type controls. Histopathological damage, inflammatory gene induction and virus load in the lungs of male mice 4 days post infection and before death were not broadly influenced by Cxcl10 deficiency. However, accumulation of B cells and both CD4+ and CD8+ T cells in the lung parenchyma of infected mice was reduced in the absence of Cxcl10. Thus, during acute SARS-CoV-2 infection, Cxcl10 regulates lymphocyte infiltration in the lung and confers protection against mortality. Our preclinical model results do not support targeting CXCL10 therapeutically in severe COVID-19.

immunology↗

bioRxiv2024

Bacterial motility patterns adapt smoothly in response to spatial confinement and disorder

In unconfined environments, bacterial motility patterns are an explicit expression of the internal states of the cell. Bacteria operating a run-and-tumble behavioral program swim forward when in a run state, and are stalled in place when in a reorienting tumble state. However, in natural environments, motility dynamics often represent a convolution of bacterial behavior and environmental constraints. Recent investigations showed that Escherichia coli swimming through highly confined porous media exhibit extended periods of trapping punctuated by forward hops, a seemingly drastic restructuring of run-and-tumble behavior. We introduce a microfluidic device to systematically explore bacterial movement in a range of spatially structured environments, bridging the extremes of unconfined and highly confined conditions. We observe that trajectories reflecting unconstrained expression of run-and-tumble behavior and those reflecting hop-and-trap dynamics coexist in all structured environments considered, with ensemble dynamics transitioning smoothly between these two extremes. We present a unifying swim-and-stall framework to characterize this continuum of observed motility patterns and demonstrate that bacteria employing a consistent set of behavioral rules can present motility patterns that smoothly transition between the two extremes. Our results indicate that the control program underlying run-and-tumble motility is robust to changes in the environment, allowing flagellated bacteria to navigate and adapt to a diverse range of complex, dynamic habitats using the same set of behavioral rules.

biophysics↗

bioRxiv2024

GPR30 in spinal cholecystokinin-positive neurons modulates neuropathic pain via mediating descending facilitation

Neuropathic pain, a major health problem affecting 7-10% of the global population, lacks effective treatment due to its elusive mechanisms. Cholecystokinin-positive (CCK+) neurons in the spinal dorsal horn (SDH) are critical for neuropathic pain, yet the underlying molecular mechanisms remain unclear. Here, we show that the membrane estrogen receptor G-protein coupled estrogen receptor (GPER/GPR30) in spinal neurons was significantly upregulated in chronic constriction injury (CCI) mice and that inhibition of GPR30 in CCK+ neurons reversed CCI-induced neuropathic pain. Furthermore, GPR30 in spinal CCK+ neurons was essential for the enhancement of AMPA-mediated excitatory synaptic transmission in CCI mice. Moreover, GPR30 was expressed in spinal CCK+ neurons that received direct projection from the primary sensory cortex (S1-SDH). Chemogenetic inhibition of S1-SDH post-synaptic neurons alleviated CCI-induced neuropathic pain. Conversely, chemogenetic activation of these neurons mimicked neuropathic pain symptoms, which were attenuated by spinal inhibition of GPR30. Finally, we confirmed that GPR30 in S1-SDH post-synaptic neurons was required for CCI-induced neuropathic pain. Taken together, our findings suggest that GPR30 in spinal CCK+ neurons and S1-SDH postsynaptic neurons is pivotal for neuropathic pain, thereby representing a promising therapeutic target for neuropathic pain.

neuroscience↗

bioRxiv2024

LRRC8 complexes are adenosine nucleotide release channels regulating platelet activation and arterial thrombosis

Platelet shape and volume changes are early mechanical events contributing to platelet activation and thrombosis. Here, we identify single-nucleotide polymorphisms in Leucine-Rich Repeat Containing 8 (LRRC8) protein subunits that form the Volume-Regulated Anion Channel (VRAC) which are independently associated with altered mean platelet volume. LRRC8A is required for functional VRAC in megakaryocytes (MKs) and regulates platelet volume, adhesion, and agonist-stimulated activation, aggregation, ATP secretion and calcium mobilization. MK-specific LRRC8A cKO mice have reduced arteriolar thrombus formation and prolonged arterial thrombosis without affecting bleeding times. Mechanistically, platelet LRRC8A mediates swell-induced ATP/ADP release to amplify agonist-stimulated calcium and PI3K-AKT signaling via P2X1, P2Y1 and P2Y12 receptors. Small-molecule LRRC8 channel inhibitors recapitulate defects observed in LRRC8A-null platelets in vitro and in vivo. These studies identify the mechanoresponsive LRRC8 channel complex as an ATP/ADP release channel in platelets which regulates platelet function and thrombosis, providing a proof-of-concept for a novel anti-thrombotic drug target.

cell biology↗

bioRxiv2024

Germinated brown rice research: bibliometric analysis of progress, hotspots and trends

To gain a deeper understanding of global research trends and focal points in germinated brown rice, this article takes the relevant literature on germinated brown rice in the core database of Web of Science as the research object. By using bibliometric analysis, the literature on germinated brown rice published from 2003 to 2023 is deeply analyzed, and the global research progress, hotspots and future development trend of germinated brown rice are summarized. Since 2018, research on germinated brown rice has been rapidly developing, with a significant surge in interest since 2020. China leads in the number of publications, institutions, and core authors in this research area. The primary research topics include the nutritional value, physiological active components, and industrial applications of germinated brown rice. Current research frontiers involve identifying, evaluating, and enhancing bioactive substances in germinated brown rice for food applications. Research in this field remains active, and application scenarios are becoming increasingly diverse. Future studies may explore new directions in related equipment and ingredients.

bioinformatics↗

bioRxiv2024

Identification of Intrinsic Features for Cortical Separability of Human and Mouse Neurons

This work introduces a novel framework for holistic comparative analysis of cortical regions in mouse and human brains at single-neuron resolution, with a primary focus on the morphological and molecular characteristics of neurons. To do so, we generated one of the largest dendritic reconstruction datasets of cortical neurons to date, comprising 2,363 human neurons and 16,011 mouse neurons from the frontal, parietal, and temporal lobes, followed by establishing a rigorous procedure to identify anatomically and functionally corresponding brain regions with minimal variability in brain mapping. Additionally, we leveraged single nucleus/cell transcriptomic data from independent groups to validate the molecular correspondence of the brain regions identified in this study. The significance of these anatomically, functionally, and molecularly corresponding mouse-human region pairs is highlighted by examining the intrinsic features of their respective cortical regions. Our findings reveal that human neuron branching patterns differ dramatically from those in mouse brains, particularly in terms of dendritic branching frequency and normalized dendritic branching intervals. This difference is pronounced in the frontal and temporal lobes, underscoring the distinct neuronal architectures between the two species. At the single-neuron level, we found that neurons from the human frontal and parietal lobes are six times more separable than those from the same regions in mouse brains. This heightened separability is also observed between the frontal and temporal lobes, as well as between the parietal and temporal lobes in humans. We thoroughly explored the entire morphological feature space, along with its characteristic subspaces, and consistently found this distinct separability. Remarkably, this neuronal separability can be partially recapitulated when examining the global functional states of these brain lobes--using newly acquired Electroencephalography (EEG) and Magnetoencephalography (MEG) signals as physiological measures--as well as their global metabolic states, molecular profiles, and cortical geometry. These findings suggest that our comparative analysis of single-neuron intrinsic features could serve as a valuable foundation for future comprehensive studies of cross-species brain structures and functions.

neuroscience↗

bioRxiv2024

Loss of Diurnal Oscillatory Rhythms in Gut Microbiota Correlates with Progression of Atherosclerosis

Circadian rhythms in gut microbiota composition are crucial for metabolic function and disease progression, yet the diurnal oscillation patterns of gut microbiota in atherosclerotic cardiovascular disease (ASCVD) and their role in disease progression remain unknown. Here, we investigate gut bacterial dynamics in ApoE-/- mice within a day, and elucidated the dynamic changes in fecal microbiota composition and function differences among C57BL/6 and ApoE-/- mice with standard chow diet or high-fat, high-cholesterol diet under ad libitum conditions. Compared with C57BL/6 mice, ApoE-/- mice exhibit significant differences in fecal microbial composition. Rhythmic analysis showed that the dynamic changes in the composition and function of fecal microbiota in ApoE-/- mice were significantly different from those in C57BL/6 mice. We further found that the rhythmic strains (Blautia Coccoides) inhibit the progression of ASCVD by improving the intestinal and endothelial barrier function. Our findings demonstrate that diurnal oscillations in gut microbiota are closely related to the progression of ASCVD, and provide a new insight for microbial-targeted therapies for ASCVD.

microbiology↗

bioRxiv2024

Diphthamide formation in Arabidopsis requires DPH1-interacting DPH2 for light and oxidative stress resistance

Diphthamide is a post-translationally modified histidine residue of eukaryotic TRANSLATION ELONGATION FACTOR 2 (eEF2) and the target of diphtheria toxin in human cells. In yeast and mammals, the 4Fe-4S cluster-containing proteins Dph1 and Dph2 catalyze the first biosynthetic step of diphthamide formation. Here we identify Arabidopsis thaliana DPH2 and show that it is required for diphthamide biosynthesis, localizes to the cytosol and interacts physically with AtDPH1. Arabidopsis dph2 mutants form shorter primary roots and smaller rosettes than the wild type, similar to dph1 mutants which we characterized previously. Additionally, increased ribosomal -1 frameshifting error rates and attenuated TARGET OF RAPAMYCIN (TOR) kinase activity in dph2 mutants also phenocopy the dph1 mutant. Beyond the known heavy-metal hypersensitivity and heat shock tolerance of dph1, we newly show here that both dph1 and dph2 mutants are hypersensitive to elevated light intensities and oxidative stress, and that wild-type Arabidopsis seedlings accumulate diphthamide-unmodified eEF2 under oxidative stress. Both mutants share the deregulation of 1,186 transcripts in numerous environmental and hormone responses. AtDPH1 and AtDPH2 do not complement the corresponding mutants of Saccharomyces cerevisiae. In summary, DPH2 and DPH1 interact to function inter-dependently in diphthamide formation, the maintenance of translational fidelity, wild-type growth rates and TOR kinase activation, and they contribute to mitigating damage from elevated light intensities and oxidative stress. Under oxidative stress, a dose-dependent loss of diphthamide could potentiate downstream effects in a feed-forward loop. This work advances our understanding of translation and its interactions with growth regulation and stress responses in plants.

plant biology↗