Biology subjects

Zhu, Z.

Publications and source records attributed to Zhu, Z..

At least 181 records · Page 10Linked to original sources

bioRxiv2023

Rme-6 integrates EGFR trafficking and signalling to regulate ERK1/2 signalosome dynamics

Epidermal growth factor receptor (EGFR) signalling results in a variety of cell behaviours, including cell proliferation, migration and apoptosis, which depend on cell context. Here we have explored how the Rab5GEF, Rme-6, regulates EGFR signalling by modulating endocytic flux. We demonstrate that Rme-6, which acts early in the endocytic pathway, regulates EGFR trafficking through an endocytic compartment that is competent for ERK1/2 signalling. While overexpression of Rme-6 results in enhanced ERK1/2 nuclear localisation and c-Fos activation, loss of Rme-6 results in aberrant ERK1/2 signalling with increased cytoplasmic ERK1/2 phosphorylation (Thr202/Tyr204) but decreased ERK1/2 nuclear translocation and c-Fos activation, the latter leading to decreased cell proliferation. Phosphorylation of ERK1/2 by protein kinase 2 (CK2) is required for its nuclear translocation and our data support a model whereby Rme-6 provides a scaffold for a population of CK2 which is required for efficient nuclear translocation of ERK1/2. Rme-6 is itself a substrate for CK2 on Thr642 and Ser996 and phosphorylation on these sites can activate its Rab5GEF activity and endocytic trafficking of EGFR. Together our results indicate that Rme-6 co-ordinates EGFR trafficking and signalling to regulate the assembly and disassembly of an ERK1/2 signalosome. Summary statementHere we demonstrate how Rme-6, a Rab5GEF, co-ordinates trafficking and signalling of EGFR on the early endocytic pathway to ensure appropriate regulation of downstream ERK1/2 signalling.

cell biology↗

bioRxiv2023

Syndecan-4 is the Key Proteoglycan Mediating LPS-induced Sepsis-associated Lung Injury

The occurrence of acute sepsis-associated lung injury (ALI) is closely related to vascular endothelial cell dysfunction, but the exact isoform of the functional syndecans (SDCs) located in the inner endothelial membrane of blood vessels and involved in regulating inflammation is not clear. The present study aimed to clarify whether SDC2 and/or 4 is involved in the inflammation process.Using the Gene Expression Omnibus (GEO) database, differentially expressed genes (DEGs) were extracted and analyzed. A bioinformatic analysis was conducted using R language, gene ontology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) with the aim of predicting SDC2 and 4 expression levels. Subsequently, the expression profiles of these two proteins were examined after construction of a sepsis-associated ALI mmodel was constructed in both human lung vascular endothelial cells (HLVEC) and animal models under inflammatory conditions. Eventually, the transcription factors (TF) of SDC2/4 were predicted based on the available dataset, and their involvement in septic inflammation was indirectly assessed. The GSE 5883 microarray gene-chip data profile was found to be suitable for analyzing lipopolysaccharide (LPS)-induced endothelial inflammatory injury. After analyzing the DEGs, 224 and 102 genes were found to be up- and down-regulated, respectively. All DEGs were involved in modulating receptor ligand and signaling receptor activator activities, cytokine receptor binding in biological processes, such as responses to lipopolysaccharide (LPS) and molecules from bacterial origins, positive regulation of cell adhesion, and other functions. In the case of localization of cellular components, most DEGs were enriched in cytoplasmic ribonucleoprotein granules, transcription regulator complex, and membrane rafts and were involved in the tumor necrosis factor (TNF) signaling and cytokine receptor interaction pathways. When compared with the control group, SDC4 gene expression in the LPS group increased by 4.5-fold, and comparable results were found in terms of SDC2 gene expression. From an experimental aspect, SDC4 was found to be markedly up-regulated with respect to mRNA and protein expression levels in response to inflammatory injury; moreover, down-regulation of SDC4 could severely exacerbate inflammatory responses either in in vivo or in vitro models. Altogether, SDC4, rather than SDC2, was found to be involved in LPS-induced sepsis-associated ALI.

bioinformatics↗

bioRxiv2023

ZBP1-mediated macrophage necroptosis inhibits ASFV replication

African swine fever (ASF) is an infectious disease characterized by hemorrhagic fever, highly pathogenic, and severe mortality in domestic pigs caused by the African swine fever virus (ASFV). ASFV is a large DNA virus and primarily infects porcine monocyte macrophages. The interaction between ASFV and host macrophages is the major reason for gross pathological lesions caused by ASFV. Necroptosis is an inflammatory programmed cell death and plays an important immune role during virus infection. However, whether and how ASFV induces macrophage necroptosis and what effect of necroptosis signaling on host immunity and ASFV infection remains unknown. This study uncovered that ASFV activates the necroptosis signaling in the spleen, lung, liver, and kidney from ASFV-infected pigs. And macrophage necroptosis also was induced by ASFV infection in vitro. Further evidence showed that the macrophage necroptosis is independent of TNF--RIPK1 or TLR-TRIF pathway but depends on Z-DNA binding protein 1 (ZBP1). ASFV infection upregulates the expression of ZBP1 and RIPK3 to consist of the ZBP1-RIPK3-MLKL necrosome and further activates macrophage necroptosis. Subsequently, multiple Z-DNA sequences were predicted to be present in the ASFV genome. And the Z-DNA signals were further confirmed to be present and colocalized with ZBP1 in the cytoplasm and nucleus of ASFV-infected cells. Moreover, ZBP1-mediated macrophage necroptosis caused the extracellular release of proinflammatory cytokines TNF- and IL-1{beta} induced by ASFV infection. Finally, we demonstrated that ZBP1-mediated necroptosis signaling significantly inhibits ASFV replication in host macrophages. Our findings uncovered a novel mechanism by which ASFV induces macrophage necroptosis by facilitating Z-DNA accumulation and ZBP1 necrosome assembly, providing significant insights into the pathogenesis of ASFV infection. ImportanceASFV infection causes an acute, febrile, hemorrhagic, and severely lethal disease in swine, which seriously threatens the global porcine industry. Understanding the interaction mechanism between ASFV and host macrophages during infection is essential for elucidating the pathogenesis of ASFV. To our knowledge, this study revealed the interaction mechanism between ASFV infection and host macrophage necroptosis. The results showed that ASFV infection induces macrophage necroptosis through ZBP1 activation instead of the TNF--RIPK1 or TLR-TRIF pathway. ASFV infection promotes Z-DNA accumulation, which causes ZBP1-RIPK3-MLKL necrosome assembly and macrophage necroptosis. The ZBP1-mediated necroptosis signaling facilitates the extracellular release of proinflammatory cytokines, inhibiting ASFV replication in host macrophages. This study found a new interaction mechanism between ASFV and host macrophages, which may help understand the pathogenesis caused by ASFV infection.

microbiology↗

bioRxiv2023

The Chromatin Landscape of Pathogenic Transcriptional Cell States in Rheumatoid Arthritis

Synovial tissue inflammation is the hallmark of rheumatoid arthritis (RA). Recent work has identified prominent pathogenic cell states in inflamed RA synovial tissue, such as T peripheral helper cells; however, the epigenetic regulation of these states has yet to be defined. We measured genome-wide open chromatin at single cell resolution from 30 synovial tissue samples, including 12 samples with transcriptional data in multimodal experiments. We identified 24 chromatin classes and predicted their associated transcription factors, including a CD8+ GZMK+ class associated with EOMES and a lining fibroblast class associated with AP-1. By integrating an RA tissue transcriptional atlas, we found that the chromatin classes represented superstates corresponding to multiple transcriptional cell states. Finally, we demonstrated the utility of this RA tissue chromatin atlas through the associations between disease phenotypes and chromatin class abundance as well as the nomination of classes mediating the effects of putatively causal RA genetic variants.

immunology↗

bioRxiv2023

Toxoplasma gondii infection alters the recognition response of dendritic cells to stiffness substrate: A new model of cell durotaxis migration

Toxoplasma gondii (T.gondii) hijacks host immune cells as Trojan Horse, and the infected cells accelerated the parasites dissemination. During acute infection, T.gondii specificity crosses the blood-brain-barrier to enter the brain. This selective mode of parasite transmission may be associated with the directed migration of infected immune cells. Immune cells follow various environmental cues for directional migration. However, the effect of T.gondii infection on the recognition of mechanical cues by immune cells remains unknown. Here, we examined the adhesion and migration of T.gondii-infected dendritic cells (DCs) on high and low stiffness substrates. We found that T.gondii infection alters the durotaxis migration of DCs. Infected DC exhibited stronger adhesion and lower migration on low stiffness substrates. In contrast to uninfected DCs, infected DCs migrated towards the low stiffness environment. TgWIP and TgROP17 co-regulate the F-actin structure of DCs and are involved in the formation of abnormal F-actin filaments. Rearrangement of the F-actin structure resulting from T.gondii infection regulates DCs abnormal recognition response to the mechanical cues. Recognition of DCs to the mechanical signals is independent of {beta}2- integrin expression. Meanwhile, challenging DCs with T.gondii increased the phosphorylation of focal adhesion kinase (FAK). Treatment with a FAK inhibitor (VS- 6063) influences the recognition response of infected DCs. FAK inhibition in adoptively transferred infected DCs effectively prevents the dissemination of T.gondii to the brain. The data reveal that T.gondii infection inversely affects the durotaxis of DCs by altering the phosphorylation level of FAK and remodeling of F-actin structure. T.gondii utilizes the change in DCs durotaxis migration to accelerate the parasites crossing the blood-brain-barrier. Author SummaryImmune cells travel through blood vessels and lymph vessels to various tissues, and respond to different types of environmental cues. Cells sense the cues and transmit these information to the cytoskeletal which induce directed cell migration towards or away from these signals. T.gondii infection remodeling the cytoskeletal of DCs which may cause abnormalities in these cues transduction. We found that T.gondii infection induces the formation of abnormal F-actin filaments in DCs, TgWIP and TgROP17 co-regulate the DCs F-actin structure. T.gondii infection increased the phosphorylation of FAK in DCs and has no effect with DCs surface {beta}2-integrin expression. These reasons lead to alter the original durotaxis migration of DCs, and makes infected-DCs tend to stay in the low stiffness environment. Meanwhile, the recognition response of infected DC to mechanical signal determines the parasite rapid crossing the blood-brain-barrier.

pathology↗

bioRxiv2023

A unifying principle for global greenness patterns and trends

Vegetation cover regulates the exchanges of energy, water and carbon between land and atmosphere. Remotely-sensed fractional absorbed photosynthetically active radiation (fAPAR), a land-surface greenness metric, depends on carbon allocation to foliage while also controlling photon flux for photosynthesis. Greenness is thus both a driver and an outcome of gross primary production (GPP). An equation with just two (globally) fitted parameters describes annual maximum fAPAR (fAPARmax) as the smaller of a water-limited value, transpiring a constant fraction of annual precipitation, and an energy-limited value, maximizing annual plant growth. This minimalist description reproduces global greenness patterns, and the consistent temporal trends among remote-sensing products, as accurately as the best-performing dynamic global vegetation models. Widely observed greening is attributed to the influence of rising carbon dioxide on the light- and water-use efficiencies of GPP, augmented by wetting in some dry regions and warming in high latitudes. Limited regions show browning, attributed to drying.

ecology↗

bioRxiv2023

Brainstem Dbh+ Neurons Control Chronic Allergen-Induced Airway Hyperreactivity

Chronic exposure of the lung to irritants such as allergen is a primary cause of asthma characterized by exaggerated airway constriction, also called hyperreactivity, which can be life-threatening. Aside from immune cells, vagal sensory neurons are important for airway hyperreactivity 1-4. However, the identity and signature of the downstream nodes of this adaptive circuit remains poorly understood. Here we show that a single population of Dbh+neurons in the nucleus of the solitary tract (nTS) of the brainstem, and downstream neurons in the nucleus ambiguous (NA), are both necessary and sufficient for chronic allergen-induced airway hyperreactivity. We found that repeated exposures of mice to inhaled allergen activates nTS neurons in a mast cell-, interleukin 4 (IL-4)-and vagal nerve-dependent manner. Single-nucleus RNA-seq of the nTS at baseline and following allergen challenges reveals that a Dbh+ population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted, while chemogenetic activation promoted hyperreactivity. Viral tracing indicates that Dbh+nTS neurons, capable of producing norepinephrine, project to the NA, and NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that then directly drive airway constriction. Focusing on transmitters, delivery of norepinephrine antagonists to the NA blunted allergen-induced hyperreactivity. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. The knowledge opens the possibility of targeted neural modulation as an approach to control refractory allergen-induced airway constriction.

cell biology↗

bioRxiv2023

In vivo Modulation of Intraocular and Intracranial Pressures Causes Nonlinear and Non-monotonic Deformations of the Lamina Cribrosa and Scleral Canal

PurposeTo evaluate changes in monkey optic nerve head (ONH) morphology under acutely controlled intraocular pressure (IOP) and intracranial pressure (ICP). MethodsSeven ONHs from six monkeys were imaged via optical coherence tomography while IOP and ICP were maintained at one of 16 conditions. These conditions were defined by 4 levels for each pressure: low, baseline, high and very high. Images were processed to determine scleral canal area, aspect ratio, and planarity and anterior lamina cribrosa (ALC) shape index and curvature. Linear mixed effect models were utilized to investigate the effects of IOP, ICP and their interactions on ONH morphological features. The IOP-ICP interaction model was compared with one based on translaminar pressure difference (TLPD). ResultsWe observed complex, eye-specific, non-linear patterns of ONH morphological changes with changes in IOP and ICP. For all ONH morphological features, linear mixed effects models demonstrated significant interactions between IOP and ICP that were unaccounted for by TLPD. Interactions indicate that the effects of IOP and ICP depend on the other pressure. The IOP-ICP interaction model was a higher quality predictor of ONH features than a TLPD model. ConclusionsIn vivo modulation of IOP and ICP causes nonlinear and non-monotonic changes in monkey ONH morphology that depend on both pressures and is not accounted for by a simplistic TLPD. These results support and extend prior findings. Translational Relevance: A better understanding of ICPs influence on the effects of IOP can help inform the highly variable presentations of glaucoma and effective treatment strategies.

bioengineering↗

bioRxiv2023

T492I mutation alters SARS-CoV-2 properties via modulating viral non-structural proteins

The historically dominant SARS-CoV-2 Delta variants and the currently dominant Omicron variants carry a T492I substitution within the non-structural protein 4 (NSP4). Based on a combination of in silico analyses, we predicted that the T492I mutation increases the transmissibility and adaptability of the virus. We confirmed this hypothesis by performing competition experiments in hamsters and in human airway tissue culture models. Furthermore, we show that the T492I mutation also increases the replication capacity and infectiveness of the virus, and improves its ability to evade antibody neutralization induced by previous variants. Mechanistically, the T492I mutation increases cleavage efficiency of the viral main protease NSP5 by enhancing enzyme-substrate binding, resulting in increased production of nearly all non-structural proteins processed by NSP5. Importantly, T492I mutation suppresses the viral RNA associated chemokines in monocytic macrophages, which may contribute to the attenuated pathogenicity of Omicron variants. Our results highlight the importance of the NSP4 mutation in the evolutionary dynamics of SARS-CoV-2 and identify a novel target for the development of broad-spectrum antiviral agents.

microbiology↗

bioRxiv2022

NR5A2 connects genome activation to the first lineage segregation in early mouse development

After fertilization, zygotic genome activation (ZGA) marks the beginning of the embryonic program for a totipotent embryo, which further gives rise to the pluripotent embryonic lineages and extraembryonic trophectoderm after the first lineage commitment. While much has been learned about pluripotency regulation, how ZGA is connected to the pluripotency commitment in early embryos remains elusive. Here, we investigated the role of nuclear receptor 1 family transcription factors (TFs) in mouse pre-implantation embryos, whose motifs are highly enriched in accessible chromatin at the 2-cell (2C) to 8-cell (8C) stages after ZGA. We found NR5A2, an NR TF highly induced upon ZGA, is required for early development, as both the knockdown and knockout of Nr5a2 from 1C embryos led to morula arrest. While the zygotic genome was largely activated at the 2C stage, 4-8C-specific gene activation (mid-preimplantation activation) was substantially impaired. Genome-wide chromatin binding and RNA-seq analyses showed NR5A2 preferentially regulates its binding targets including a subset of key pluripotency genes (i.e., Nanog, Pou5f1, and Tdgf1). Finally, NR5A2-occupied sites at the 2C and 8C stages predominantly reside in accessible B1 elements where its motif is embedded. Taken together, these data identify NR5A2 as a key regulator that connects ZGA to the first lineage segregation in early mouse development.

developmental biology↗

bioRxiv2022

A genome wide association study identifies a new variant associated with word reading fluency in Chinese children

Reading disability exhibited defects in different cognitive domains, including word reading fluency, word reading accuracy, phonological awareness, rapid automatized naming, and morphological awareness. To identify the genetic basis of Chinese reading disability, we conducted a genome wide association study (GWAS) of the cognitive traits related to Chinese reading disability in 2284 unrelated Chinese children. Among the traits analyzed in the present GWAS, we detected one genome wide significant association (p<5x10-8) on reading fluency for one SNP on 4p16.2, within EVC genes (rs6446395, p=7.55x10-10). Rs6446395 also showed significant association with word reading accuracy (p=3.39x10-4), phonological awareness (p=7.12x10-3), and rapid automatized naming (p=4.71x10-3), implying multiple effects of this variant. Gene-based analyses identified a gene to be associated with reading fluency at the genome-wide level. The eQTL data showed that rs6446395 affected EVC expression in the cerebellum. Our study discovered a new candidate susceptibility variant for reading ability and provide new insights into the genetics of development dyslexia in Chinese Children.

genetics↗

bioRxiv2022

A genome-wide association study identified new variants associated with mathematical abilities in Chinese children

Mathematical ability is moderately heritable, and it is a complex trait which can be evaluated in several different categories. A few genetic studies have been published on general mathematical ability. However, no genetic study focused on specific mathematical ability categories. In this study, we separately performed genome-wide association studies (GWASs) on 11 mathematical ability categories in 1 146 students from Chinese elementary schools. We identified 7 genome-wide significant single nucleotide polymorphisms (SNPs) with strong linkage disequilibrium (LD) among each other (all r2>0.8) associated with mathematical reasoning ability (top SNP: rs34034296, p=2.01x10-8, nearest gene: CUB and Sushi multiple domains 3, CSMD3). We replicated one SNP (rs133885) from 585 SNPs previously reported to be associated with general mathematical ability associated with division ability in our data (p=1.053x10-5). In the gene- and gene-set enrichment analysis by MAGMA, we found three significant enrichments of associations with three mathematical ability categories for three genes. We also observed four significant enrichments of associations with four mathematical ability categories for three gene sets. Our results suggest new candidate genetic loci for the genetics of mathematical ability.

genetics↗

bioRxiv2022

Network-based hub biomarker discovery for glaucoma

Glaucoma is an optic neuropathy, and the leading cause of irreversible blindness worldwide. However, the early detection of glaucoma remains challenging as chronic forms of glaucoma remain largely asymptomatic until considerable irreversible visual field deficits have ensued. Thus, biomarkers that facilitate early diagnosis and treatment for patients with a high risk of progression are critical. Network medicine approaches can be useful in identifying key relationships and important biomolecules for complex diseases. In this paper, we identified several hub biomarkers/drug targets for the diagnosis, treatment and prognosis for glaucoma and explored their associations for glaucoma based on human disease-biomarker and disease-target-drug networks. These results were verified by text-mining and genomic/epidemiology data. We also predicted the new application of BMP1 and MMP9 to diagnose glaucoma and confirm the theory of hub biomarkers with multiple clinical applications. Further, relevant pivotal pathways (regulation of the multicellular organismal process, regulation of localisation, and cytoplasmic vesicle for biomarkers; signal transduction and developmental process for targets) for these hub biomolecules were discovered, which may be foundations for future biomarker and drug target prediction for glaucoma. In conclusion, based on complex networks, hub biomolecules, essential pathways, and close diseases were identified for glaucoma in diagnosis, treatment and prognosis.

bioinformatics↗

bioRxiv2022

Highly Sensitive and Specific Amyloid-β Oligomers Detection Using CRISPR-Cas12a Probe System aided by Graphene Oxide for Early Diagnosis of Alzheimer's Diseases

Alzheimers disease (AD) is highly age-specific that results in cognitive incapability including dementia. It is proposed that AD is caused by the dysfunctional gene producing excessive amyloid-{beta} protein that eventually results in aggregated form of amyloid-{beta} Oligomers (A{beta}O). We couple the CRISPR-Cas12a system with a specially designed single-stranded DNA (ssDNA) aptamer that specifically forms a hybrid complex with A{beta}O. We exploit the aptamer as the substrate for the crRNA-aptamer duplex due to its high flexibility, sensitivity, and selectivity. We further adopted the graphene oxide (GO) fluorescent system to couple with our CRISPR-Cas12a probe system. Our coupled probe system can effectively detect the presence of A{beta}O by quantitatively returning fluorescent signals with high specificity and accuracy.

biochemistry↗

bioRxiv2022

Multifaceted modes of γ-tubulin complex recruitment and microtubule nucleation at mitotic centrosomes

Microtubule nucleation is mediated by {gamma}-tubulin ring complexes ({gamma}-TuRCs). In most eukaryotes, a GCP4/5/4/6 "core" complex promotes {gamma}-tubulin small complex ({gamma}-TuSC) association to generate cytosolic {gamma}-TuRCs. Unlike {gamma}-TuSCs, however, this core complex is non-essential in various species and absent from budding yeasts. In Drosophila, Spindle defective-2 (Spd-2) and Centrosomin (Cnn) redundantly recruit {gamma}-tubulin complexes to mitotic centrosomes. Here we show that Spd-2 recruits {gamma}-TuRCs formed via the GCP4/5/4/6 core, but that Cnn can recruit {gamma}-TuSCs directly via its well-conserved CM1 domain, similar to its homologues in budding yeast. When centrosomes fail to recruit {gamma}-tubulin complexes, they still nucleate microtubules via the TOG domain protein Mini-spindles (Msps), but these microtubules have different dynamic properties. Our data therefore help explain the dispensability of the GCP4/5/4/6 core and highlight the robustness of centrosomes as microtubule organising centres. They also suggest that the dynamic properties of microtubules are influenced by how they were nucleated.

cell biology↗

bioRxiv2022

Guild-level microbiome signature associated with COVID-19 severity and prognosis

COVID-19 severity has been associated with alterations of the gut microbiota. However, the relationship between gut microbiome alterations and COVID-19 prognosis remains elusive. Here, we performed a genome-resolved metagenomic analysis on fecal samples collected from 300 in-hospital COVID-19 patients at time of admission. Among the 2,568 high quality metagenome-assembled genomes (HQMAGs), Redundancy Analysis identified 33 HQMAGs which showed differential distribution among mild, moderate, and severe/critical severity groups. Random Forest model based on these 33 HQMAGs classified patients from different severity groups (average AUC = 0.79). Co-abundance network analysis found that the 33 HQMAGs were organized as two competing guilds. Guild 1 harbored more genes for short-chain fatty acid biosynthesis, and fewer genes for virulence and antibiotic resistance, compared with Guild 2. Random Forest regression showed that these 33 HQMAGs at admission had the capacity to predict 8 clinical parameters, which are predictors for COVID-19 prognosis, at Day 7 in hospital. Moreover, the dominance of Guild 1 over Guild 2 at admission predicted the death/discharge outcome of the critical patients (AUC = 0.92). Random Forest models based on these 33 HQMAGs classified patients with different COVID-19 symptom severity, and differentiated COVID-19 patients from healthy subjects, non-COVID-19, and pneumonia controls in three independent datasets. Thus, this genome-based guild-level signature may facilitate early identification of hospitalized COVID-19 patients with high risk of more severe outcomes at time of admission.

microbiology↗

bioRxiv2022

An R-R-type MYB transcription factor promotes nonclimacteric pepper fruit ripening pigmentation

Carotenoids act as phytohormones and volatile compound precursors that influence plant development and confer characteristic colours, affecting both the aesthetic and nutritional value of fruits. Carotenoid pigmentation in ripening fruits is highly dependent on developmental trajectories. Transcription factors incorporate developmental and phytohormone signalling to regulate the biosynthesis process. In contrast to the well-established pathways regulating ripening-related carotenoid biosynthesis in climacteric fruit, carotenoid regulation in nonclimacteric fruit is poorly understood. Capsanthin is the primary carotenoid of nonclimacteric pepper (Capsicum) fruit; its biosynthesis is tightly associated with fruit ripening, and it confers red pigment to the ripening fruit. In this study, using a weighted gene coexpression network and expression analysis, we identified an R-R-type MYB transcription factor, DIVARICATA1, and demonstrated that it is tightly associated with the levels of carotenoid biosynthetic genes (CBGs) and capsanthin accumulation. DIVARICATA1 encodes a nucleus-localized protein that functions primarily as a transcriptional activator. Functional analyses demonstrated that DIVARICATA1 positively regulates CBG transcript levels and capsanthin contents by directly binding to and activating the CBG promoter transcription. Furthermore, the association analysis revealed a significant positive association between DIVARICATA1 transcription level and capsanthin content. Abscisic acid (ABA) promotes capsanthin biosynthesis in a DIVARICATA1-dependent manner. Comparative transcriptomic analysis of DIVARICATA1 in pepper and its orthologue in a climacteric fruit, tomato, suggests that its function might be subject to divergent evolution among the two species. This study illustrates the transcriptional regulation of capsanthin biosynthesis and offers a novel target for breeding peppers with high red colour intensity.

plant biology↗

bioRxiv2022

An exotic allele of barley EARLY FLOWERING 3 contributes to developmental plasticity at elevated temperatures

Increase in ambient temperatures caused by climate change affects various morphological and developmental traits of plants, threatening crop yield stability. In the model plant Arabidopsis thaliana, EARLY FLOWERING 3 (ELF3) plays prominent roles in temperature sensing and thermomorphogenesis signal transduction. However, how crop species respond to elevated temperatures is poorly understood. Here, we show that the barley ortholog of AtELF3 interacts with high temperature to control growth and development. We used heterogeneous inbred family (HIF) pairs generated from a segregating mapping population and systematically studied the role of exotic ELF3 variants in barley temperature responses. An exotic ELF3 allele from Syrian origin promoted elongation growth in barley at elevated temperatures, whereas plant area and estimated biomass were drastically reduced, resulting in an open canopy architecture. The same allele accelerated inflorescence development at high temperature, which correlated with early transcriptional induction of MADS-box floral identity genes BM3 and BM8. Consequently, barley plants carrying the exotic ELF3 allele displayed stable total grain number and mitigated yield loss at elevated temperatures. Our findings therefore demonstrate that exotic ELF3 variants can contribute to phenotypic and developmental acclimation to elevated temperatures, providing a stimulus for breeding of climate resilient crops. HighlightWe demonstrate that an exotic allele of EARLY FLOWERING 3 (ELF3) contributes to plant architectural and developmental acclimation, and thereby improves yield stability at high ambient temperatures.

plant biology↗