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Biology subjects

Jia, Y.

Publications and source records attributed to Jia, Y..

At least 55 records · Page 3Linked to original sources

Cocaine Blocks Cholinergic Activity in the Medial Habenula Prior to But Not After Induced Preference for the Drug

Descending projections from the medial habenula potently influence brainstem systems associated with reward and mood. Relatedly, the ventral, cholinergic segment of the nucleus has been linked to nicotine and cocaine addiction. Here we report that cocaine has no effect on baseline firing in the ventral medial habenula but entirely blocks the self-sustained activity initiated by endogenous acetylcholine. This effect was not altered by antagonists to dopamine receptors and thus presumably reflects a direct action on cholinergic receptors. Remarkably, cocaine had no effect on endogenous cholinergic activity in mice that had been extinguished from an induced cocaine preference. In all, the drug has potent effects, albeit through an exotic mode of action, on the medial habenula and these are eliminated by prior experience with the drug. These results describe a novel target for cocaine that is plausibly related to the psychological effects of the drug, and an unexpected consequence of earlier use.

neuroscience↗

An Enhanced Mountain Climbing Search Algorithm to Enable Fast and Accurate Autofocusing in High Resolution Fluorescence Microscopy

Accurate and efficient autofocusing is essential for the automation of fluorescence microscopy, but background noise and shallow depth of field at high magnifications make autofocusing particularly challenging. Here, we present a fast and accurate autofocus algorithm to address these challenges. It is highly effective for high-magnification imaging, while performing equally well for low-magnification imaging tasks. The method is based on the mountain climbing search algorithm and yields improvements on autofocusing precision of up to 200-fold over current methods, whilst offering competitive speed and greatly extended search ranges. Our approach is broadly applicable: it demonstrated good stability and reproducibility across magnifications ranging from 20X to 100X, excels in both live cell imaging and high-resolution fixed sample imaging, and it is compatible with various microscopy techniques without the need for fiducial markers or hardware modifications on existing microscopes. To maximise its accessibility, we constructed a user-friendly interface compatible with the widely used Micromanager software. It generalises well across various imaging modalities and hardware platforms, making it particularly suitable for use in high-resolution screening of candidate drugs.

cell biology↗

Red Light-Activated Reversible Inhibition of Protein Functions by Assembled Trap

Red light offers strong tissue penetration and low phototoxicity, making it an attractive option for optogenetic applications. However, the available red light-inducible optogenetic tools are rather limited. Here, we present a novel red light-induced protein clustering system, namely R-LARIAT (Red Light-Activated Reversible Inhibition by Assembled Trap), that controls protein functions in a spatiotemporal manner. Our system capitalizes on the rapid and reversible binding of LDBs (nanobodies-based dimerization binders) to a bacterial phytochrome DrBphP, which uses a mammalian endogenous biliverdin chromophore to absorb red light. An anti-GFP nanobody fused with LDBs allows this method to quickly trap a wide variety of GFP-tagged proteins into light-induced protein clusters. Strikingly, our system exhibits an excellent performance in clustering efficiency with high light sensitivity and stability, it can function even when shielded by multiple glass plates. By utilizing the R-LARIAT system to trap and sequester tubulin, cell cycle progression can be blocked in HeLa cells. Therefore, the R-LARIAT system takes advantage of red light with greater tissue penetration and holds the potential to precisely control protein functions in living organisms.

cell biology↗

Title: Cell-autonomous and non-cell-autonomous effects of TRIM72 on ALS disease progression

Dysfunction of RNA-binding proteins, including TDP-43 and FUS, has been associated with amyotrophic lateral sclerosis (ALS); however, the underlying mechanisms are largely unknown. Here, we reported that a neuronal upregulation of TRIM72 (Tripartite Motif Containing 72) in FUS mutation knockin ALS models slows disease progression. TRIM72 interacts with Commander, a protein complex for recycling of membrane proteins, facilitating membrane repair and antioxidation. Exosomal TRIM72 is detected in ALS patient cerebrospinal fluid (CSF) and extracellular application of exosomal TRIM72 protects cell from membrane damage. In a sporadic ALS cohort, CSF TRIM72 level associates ALS disease progression. AAV-mediated neuronal expression of TRIM72 slows down the disease progressions in ALS models and in an ALS patient without adverse effects over a year treatment course. Taken together, our results suggest a universal neuronal protection of a TRIM family protein in cell-autonomous and non-cell-autonomous manners in ALS.

neuroscience↗

METTL3 Aggravates Intimal Hyperplasia by Facilitating the m6A-YTHDC1-dependent SGK1 Gene Transcription

BackgroundVascular smooth muscle cell (VSMC) migration and proliferation substantially contribute to neointimal hyperplasia related to in-stent restenosis. N6-methyladenosine (m6A) catalyzed by the methyltransferase-like 3 (METTL3)-involved methyltransferase complex is the most abundant RNA epigenetic modification in eukaryotes, but the role of m6A RNA methylation in VSMC migration and proliferation as well as neointima formation remains highly controversial. MethodsPrimary human and rat VSMCs were utilized for in vitro experiments. VSMC-specific METTL3 knockout mice (Mettl3flox/floxMyh11-CreERT2) were generated to explore wire injury in carotid arteries in vivo. Methylated RNA immunoprecipitation sequencing (MeRIP-Seq) was performed to screen for target genes by METTL3-catalyzed m6A RNA methylation. Methylation site mapping, MeRIP-quantitative PCR (MeRIP-qPCR), chromatin immunoprecipitation-qPCR (ChIP-qPCR) and reporter gene assays were applied to explore how METTL3 modulates its target gene expression. ResultsMETTL3 was consistently upregulated in the neointima from mice subjected to carotid wire injury and patients undergoing carotid endarterectomy. VSMC-specific METTL3 deficiency significantly attenuated neointima formation in carotid arteries following wire injury in mice. Accordingly, METTL3 ablation markedly repressed VSMC proliferation both in vitro and in vivo. Mechanistically, METTL3 directly catalyzed m6A methylation on serum/glucocorticoid regulated kinase 1 (SGK1) mRNA and subsequently facilitated its transcription, which relies on the established association between the SGK1 transcript and SGK1 promoter DNA by recruiting the m6A reader YTHDC1. Conversely, SGK1 overexpression abolished METTL3 deficiency-mediated suppression of VSMC proliferation and postinjury neointima formation. ConclusionsMETTL3-catalyzed m6A RNA methylation promoted VSMC proliferation and aggravated postinjury neointima formation by facilitating YTHDC1-dependent SGK1 gene transcription. Targeting the METTL3-YTHDC1-SGK1 axis to modulate VSMC proliferation may be a potential strategy for in-stent restenosis therapy.

molecular biology↗

Melatonin attenuates kidney injury by alleviating lysosomal damage in diabetic kidney disease

Proteinuria-induced damage to renal tubular epithelial cells is one of the main causes of diabetic kidney disease (DKD), and the clearance of overloaded albumin by lysosomes is crucial for maintaining the homeostasis of renal tubular epithelial cells. Therefore, lysosomal damage is closely related to the pathogenesis of DKD, but effective prevention and treatment measures are still lacking. Melatonin (MLT) is secreted by the pineal gland and can not only regulate circadian rhythms but also maintain lysosomal homeostasis. In this study, we demonstrate the presence of significant lysosomal damage in renal tubules of DKD patients, which causes autophagy impairment and a concomitant oxidative stress imbalance; however, MLT can upregulate transcription factor EB (TFEB) to improve lysosomal damage and restore the biosynthesis in this organelle. Mechanistically, MLT may protect lysosomes via the upregulation of TFEB and the miR-205-5p-LRP-1 pathway in renal tubules, thus improving autophagy dysfunction and oxidative imbalance in DKD.

pathology↗

Early-life Oxytocin Rescues Hippocampal Synaptic Plasticity and Episodic Memory in a Mouse Model of Fragile X Syndrome

Cognitive disabilities including impairments to episodic memory are debilitating features of autism spectrum disorder (ASD). Here we report that early-life treatment with oxytocin (OXT) fully restores episodic memory and associated synaptic plasticity in a rodent model of an ASD. Fmr1-knockout (KO) mice -- which mimic the single gene mutation in Fragile X Syndrome -- failed to encode three basic elements of an episode (identity, location, and temporal order) during a first time, unrewarded encounter with a set of cues. Intranasal administration of OXT during the second postnatal week eliminated each of these impairments in mice tested in adulthood. OXT treatment during the second, but not fifth, postnatal week also corrected pronounced defects in two distinct forms of hippocampal Long-Term Potentiation (LTP). Rescue of LTP in lateral perforant path (LPP) to dentate gyrus synapses was linked to recovery of NMDAR-gated synaptic responses, which are otherwise profoundly reduced in the mutant LPP. LTP induced by a threshold theta burst stimulation protocol in CA3-CA1 synapses was severely impaired in adult Fmr1-KOs as was a previously unreported post-induction growth phase for potentiation. Both effects were restored in adult Fmr1-KOs given early OXT treatment. Infusion of OXT into adult Fmr1-KO hippocampal slices normalized LTP in CA1 but had no effect on the defective potentiation (or NMDAR-mediated EPSCs) at LPP-dentate gyrus synapses. These results show that severe, autism-related defects in cognition critical to memory, as evident in a rodent model, are reversible and that an early-life therapeutic intervention can effect an enduring restoration of function.

neuroscience↗

Loss of olfaction reduces caterpillar performance and increases susceptibility to a natural enemy

Insect herbivores such as caterpillars, are under strong selection pressure from natural enemies, especially parasitoid wasps. Although the role of olfaction in host-plant seeking has been investigated in great detail in parasitoids and adult lepidopterans, the caterpillar olfactory system and its significance in tri-trophic interactions remain poorly understood. In this study, we investigated the olfactory system of Pieris brassicae caterpillars and the importance of olfactory information in the interactions among this herbivore, its host plant Brassica oleracea and its primary natural enemy Cotesia glomerata. To examine the role of olfaction, we utilized CRISPR/Cas9 to knockout the odorant receptor co-receptor (Orco). This knockout (KO) impaired olfactory detection and primary processing in the brain. Orco KO caterpillars exhibited reduced weight and lost preference for their optimal food plants. Interestingly, the KO caterpillars also experienced reduced weight when challenged by the parasitoid C. glomerata whose ovipositor had been removed, and the mortality of the KO caterpillars under the attack of unmanipulated parasitoids increased. We then investigated the behavior of P. brassicae caterpillars in response to volatiles from plants attacked by conspecific caterpillars and volatiles from plants on which the caterpillars were themselves attacked by C. glomerata. After analyzing the volatile compounds involved in these interactions, we concluded that olfactory information enables caterpillars to locate suitable food sources more efficiently as well as to select enemy-free spaces. Our results reveal the crucial role of olfaction in caterpillar feeding and natural-enemy avoidance, highlighting the significance of chemoreceptor genes in shaping ecological interactions.

ecology↗

Influenza A Virus H7 nanobody recognizes a conserved immunodominant epitope on hemagglutinin head and confers heterosubtypic protection

Influenza remains a persistent global health challenge, largely due to the virus continuous antigenic drift and shift, which impede the development of a universal vaccine. To address this, the identification of broadly neutralizing antibodies and their epitopes is crucial. Nanobodies, with their unique characteristics and binding capacity, offer a promising avenue to identify such epitopes. Here, we isolated and purified a hemagglutinin (HA)-specific nanobody that recognizes an H7 subtype of influenza A virus. Notably, the nanobody, named E10, exhibited broad-spectrum binding, cross-group neutralization and in vivo protection across various influenza A subtypes. Through phage display and in vitro characterization, we demonstrated that E10 specifically targets an epitope on HA head. This epitope is part of the conserved lateral patch of HA head and proved to be highly immunodominant upon H7 infection. Importantly, immunization with a peptide including the E10 epitope elicited cross-reactive antibodies and mediated partial protection from lethal viral challenge. Our data highlight the potential of E10 and its associated epitope as a candidate for future influenza prevention strategies.

microbiology↗

Decipher Fundamental Atomic Interactions to Unify Generative Molecular Docking and Design

Understanding molecular interactions is essential to structural biology and drug discovery. Despite the progress of AI models in revealing and exploiting the interaction mechanisms for various applications, they are predominantly tailored to specific tasks without fully exploiting the underlying transferability across molecular data and tasks. Here, we present PocketXMol, an atom-level generative foundation model to decipher fundamental atomic interactions for general protein-pocket-interacting molecular tasks. It adopts a novel unified generative framework with an innovative task prompt mechanism and an exclusive atom-level representation, making it applicable to diverse tasks covering structure prediction and design of small molecules and peptides, without requiring fine-tuning. PocketXMol was compared to 55 baseline models across 13 typical tasks, achieving state-of-the-art performance in 11 tasks and remaining competitive in the others. We successfully utilized PocketXMol to design novel small molecules that inhibit caspase-9 with efficacy comparable to that of commercial pan-caspase inhibitors. Furthermore, we employed PocketXMol to design PD-L1-binding peptides, demonstrating a success rate substantially higher than random library screening. Three representative peptides underwent further experiments, which validated the cellular specificity and confirmed their potential for molecular probing and therapeutics. PocketXMol presents a powerful and versatile tool with promising prospects for future applications and will have a profound impact on AI-aided drug discovery.

bioinformatics↗

A nanobody-based approach to capture and visualize interactions of binary protein complexes in living cells

Protein interaction networks (or interactomes) are formed progressively, each interaction influencing the next one. Accordingly, a same protein will establish different interactomes depending on its first associated cofactor, thereby diversifying its function in the cell. In contrast to their central role, few methods exist to capture interactomes of dimeric protein complexes. Here, we tackle this issue by introducing an innovative method based on bimolecular fluorescence complementation and the specific binding of a nanobody fused to a proximity-dependent biotinylating enzyme. This method was applied to visualize and capture specific interactions of the cytoplasmic TAZ/14-3-3e and nuclear TAZ/TEAD2 complexes, which are major downstream effectors of the Hippo signaling pathway. Among other interactions, we identified SERPINB4 as a novel regulator of TAZ and 14-3-3e proliferative activity in mesenchymal stromal cells. Molecular dissections in living cells revealed the central role of a unique residue of TAZ for recruiting SERPINB4 specifically in the presence of 14-3-3e. Overall, our work demonstrates the importance of considering binary protein complexes for deciphering interactomes and establishes a novel sensitive method in this perspective.

molecular biology↗

Discovery of novel 1,4-dicarbonylthiosemicarbazides as DNA gyrase inhibitors for the treatment of MRSA infection

Antibiotic resistance has become a serious threat to public health, thus novel antibiotics are urgently needed to combat drug-resistant bacteria including MRSA (methicillin-resistant S. aureus). The 1,4-dicarbonylthiosemicarbazide is an interesting chemotype that could exhibit antibacterial activity. However, the currently available compounds are not as potent as clinical antibiotics. Herein, we adopted the computer-aided drug design strategy, substructure search, to retrieve antibacterial 1,4-dicarbonylthiosemicarbazide derivatives, and identified compound B5 (Specs ID: AG-690/15432331) from the Specs chemical library that exhibited moderate activity (minimum inhibitory concentration (MIC): 6.25 {micro}g/mL) against S. aureus (ATCC 29213). Based on that compound, we further designed and synthesized 45 derivatives, and evaluated their antibacterial activity. Eight derivatives were more potent than or equivalent to vancomycin (MIC: 1.56 {micro}g/mL). We compared the three most potent ones for their cytotoxicity to HepG2 and HUVEC cells and selected compound 1b as our lead compound for comprehensive biological evaluation. As a result, compound 1b exhibited a bacteriostatic mode, and was active against a panel of gram-positive bacteria strains, metabolically stable, and effective to protect the mice from MRSA infection. More importantly, we applied 2D similarity calculation and reverse docking to predict potential targets of compound 1b. Through experimental validation and molecular dynamics simulation, we were able to confirm that compound 1b inhibited S. aureus DNA gyrase (IC50: 1.81 {micro}M) and DNA supercoiling, potentially by binding to the ATPase domain, where ASP81, GLU58 and GLN91 formed key hydrogen bonds. Taken together, we have discovered a new class of DNA gyrase inhibitors represented by compound 1b for the treatment of MRSA infection, through the design, synthesis, and biological evaluation of novel 1,4-dicarbonylthiosemicarbazides. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=137 SRC="FIGDIR/small/611349v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@549dadorg.highwire.dtl.DTLVardef@13bff64org.highwire.dtl.DTLVardef@1fc2c00org.highwire.dtl.DTLVardef@acee76_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIAn interesting 1,4-dicarbonylthiosemicarbazide derivative B5 with moderate antibacterial activity for S. aureus was discovered by substructure search. C_LIO_LIBased on B5, 45 new 1,4-dicarbonylthiosemicarbazides were designed, synthesized and biologically evaluated, which led to the discovery of a promising lead compound 1b. C_LIO_LICompound 1b exhibited good antibacterial activity for a panel of gram-positive bacteria strains, and was effective to protect mice from MRSA infection. C_LIO_LIThe 1,4-dicarbonylthiosemicarbazides represented by compound 1b were discovered as a new class of DNA gyrase inhibitors, by target prediction and experimental validation. C_LI

pharmacology and toxicology↗

Herbivore prevalence poorly predicts yield in diverse cropping systems

Industrialized agriculture needs sustainable alternatives to pesticides to avoid negative impacts on the environment and human health. Crop diversification is known to decrease pest pressure in agricultural crops. Up till now, effects of insect herbivores on crop yield are often assumed equal among cropping systems. Here, we show that cropping system alters the effect that herbivores have on cabbage crop yield, where more herbivores do not necessarily lead to reduced yields. Our most diverse cropping system had simultaneously the highest number of herbivores and highest crop yield. Conversely, in a cultivar mixture we observed negative impacts of herbivores on yield. Our study shows that, in addition to the time of arrival and type of herbivore, cropping system should be considered when assessing how insect herbivores affect crop yield. We emphasize how our perception of herbivorous insects as pests is flawed and limits conservation efforts and sustainable farming practices.

ecology↗

Deep contrastive learning enables genome-wide virtual screening

Numerous protein-coding genes are associated with human diseases, yet approximately 90% of them lack targeted therapeutic intervention. While conventional computational methods, such as molecular docking, have facilitated the discovery of potential hit compounds, the development of genome-wide virtual screening against the expansive chemical space remains a formidable challenge. Here we introduce DrugCLIP, a novel framework that combines contrastive learning and dense retrieval to achieve rapid and accurate virtual screening. Compared to traditional docking methods, DrugCLIP improves the speed of virtual screening by up to seven orders of magnitude. In terms of performance, DrugCLIP not only surpasses docking and other deep learning-based methods across two standard benchmark datasets, but also demonstrates high efficacy in wet-lab experiments. Specifically, DrugCLIP successfully identified agonists with < 100 nM affinities for 5HT2AR, a key target in psychiatric diseases. For another target NET, whose structure is newly solved and not included in the training set, our method achieved a hit rate of 15%, with 12 diverse molecules exhibiting affinities better than bupropion. Additionally, two chemically novel inhibitors were validated by structure determination with Cryo-EM. Finally, a novel potential drug target TRIP12, with no experimental structures and inhibitors for reference, was used to challenge DrugCLIP. DrugCLIP achieved a hit rate of 17.5% by screening a pocket identified on an AlphaFold2-predicted structure, verified with multi-cycle SPR assays. Molecules with the highest affinities also showed a dose-dependent inhibition to the enzymatic function of TRIP12. Building on this foundation, we present the results of a pioneering trillion-scale genome-wide virtual screening, encompassing approximately 10,000 AlphaFold2 predicted proteins within the human genome and 500 million molecules from the ZINC and Enamine REAL database. This work provides an innovative perspective on drug discovery in the post-AlphaFold era, where comprehensive targeting of all disease-related proteins is within reach.

bioinformatics↗

Signal peptidase SpsB coordinates staphylococcal cell cycle, surface protein septal trafficking and LTA synthesis

Many cell wall anchored surface proteins of Gram-positive bacteria harbor a highly conserved YSIRK/G-S signal peptide (SPYSIRK+), which deposits surface protein precursors at the cell division septum where they are subsequently anchored to septal peptidoglycan. Previously we identified that LtaS-mediated lipoteichoic acid (LTA) synthesis regulates septal trafficking of YSIRK+ proteins in S. aureus. Interestingly, both LtaS and SPYSIRK+ are cleaved by the signal peptidase SpsB, but the biological implications remain unclear. Here we show that SpsB is required for cleaving SPSpA(YSIRK+) of staphylococcal surface protein A (SpA). Depletion of spsB not only diminished SPSpA processing but also abolished SpA septal localization. The mis-localization is attributed to the cleavage activity of SpsB, as an A37P mutation of SPSpA that disrupted SpsB cleavage also abrogated SpA septal localization. Strikingly, depletion of spsB led to aberrant cell morphology, cell cycle arrest and daughter cell separation defects. Localization studies showed that SpsB predominantly localized at the septum of dividing staphylococcal cells. Finally, we show that SpsB spatially regulates LtaS as spsB depletion enriched LtaS at the septum. Collectively, the data suggest a new dual-mechanism model mediated by SpsB: the abundant YSIRK+ proteins are efficiently processed by septal localized SpsB; SpsB cleaves LtaS at the septum, which spatially regulates LtaS activity contributing to YSIRK+ proteins septal trafficking. The study identifies SpsB as a novel and key regulator orchestrating protein secretion, cell cycle and cell envelope biogenesis. ImportanceSurface proteins containing a YSIRK/G-S positive signal peptide are widely distributed in Gram-positive bacteria and play essential roles in bacterial pathogenesis. They are highly expressed proteins that are enriched at the septum during cell division. The biogenesis of these proteins is coordinated with cell cycle and LTA synthesis. The current study identified the staphylococcal signal peptidase SpsB as a key determinant in regulating surface protein septal trafficking. Furthermore, this study highlights the novel functions of SpsB in coordinating LtaS-mediated LTA production and regulating staphylococcal cell cycle. As SpsB, YSIRK+ proteins and LTA synthesis are widely distributed and conserved, the mechanisms identified here may be shared across Gram-positive bacteria.

microbiology↗

Single-cell and spatial transcriptomics of vulvar lichen sclerosus reveal multicompartmental alterations in gene expression and signaling cross-talk

Vulvar diseases are a critical yet often neglected area of womens health, profoundly affecting patients quality of life and frequently resulting in long-term physical and psychological challenges. Lichen sclerosus (LS) is a chronic inflammatory skin disorder that predominantly affects the vulva, leading to severe itching, pain, scarring, and an increased risk of malignancy. Despite its profound impact on affected individuals, the molecular pathogenesis of vulvar LS (VLS) is not well understood, hindering the development of FDA-approved therapies. Here, we utilize single-cell and spatial transcriptomics to analyze lesional and non-lesional skin from VLS patients, as well as healthy control vulvar skin. Our findings demonstrate histologic, cellular, and molecular heterogeneities within VLS, yet highlight unifying molecular changes across keratinocytes, fibroblasts, immune cells, and melanocytes in lesional skin. They reveal cellular stress and damage in fibroblasts and keratinocytes, enhanced T cell activation and cytotoxicity, aberrant cell-cell signaling, and increased activation of the IFN, JAK/STAT, and p53 pathways in specific cell types. Using both monolayer and organotypic culture models, we also demonstrate that knockdown of select genes, which are downregulated in VLS lesional keratinocytes, partially recapitulates VLS-like stress-associated changes. Collectively, these data provide novel insights into the pathogenesis of VLS, identifying potential biomarkers and therapeutic targets for future research.

genomics↗

ESPRESSO: Spatiotemporal omics based on organelle phenotyping

Omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, have been instrumental to improving our understanding of complex biological systems. Despite fast-pace advancements, a crucial dimension is still left to explore: time. To capture this key parameter, we introduce ESPRESSO (Environmental Sensor Phenotyping RElayed by Subcellular Structures and Organelles), a pioneering technique that provides high-dimensional phenotyping resolved in space and time. Through a novel paradigm, ESPRESSO combines fluorescent labeling, advanced microscopy and bioimage and data analysis to extract morphological and functional information of the organelle network unveiling phenotypic changes over time at the single-cell level. In this work, we present ESPRESSOs methodology and its application across numerous cellular systems, showcasing its ability to discern cell types, stress response, differentiation and immune cells polarization. We then correlate ESPRESSO phenotypic changes with gene expression and demonstrate its applicability to 3D cultures, offering a path to revolutionizing biological exploration, providing invaluable insights into cellular states in both space and time.

bioengineering↗

Receptor-ligand interactions in plant inmate immunity revealed by AlphaFold protein structure prediction

One of the common mechanisms to trigger plant innate immunity is recognition of pathogen avirulence gene products directly by products of major resistance (R) genes in a gene for gene manner. In the USA, the R genes, Pik-s, PiKh/m, and Pi-ta, Pi-39(t), and Ptr genes have been effectively deployed to prevent the infections of M. oryzae races, IB49, and IC17 for some time. Pi-9 is only recently being deployed to provide overlapped and complimentary resistance to Magnaporthe oryzae races IB49, IC17 and IE1k in the USA. Pi-ta, Pi-39(t), Pi9 are major nuclear binding site-leucine rich (NLR) proteins, and Ptr is an atypical R protein with 4 armadillo repeats. AlphaFold is an artificial intelligence system that predicts a protein 3D structure from its amino acid sequence. Here we report genome sequence analyses of the effectors and avirulence (AVR) genes, AVR-Pita and AVR-Pik, and AVR-Pi9, in 3 differential M. oryzae races. Using AlphaFold 2 and 3 we find strong evidence of direct interactions of products of resistance genes Pi-ta and Pik with M. oryzae avirulence (AVR) genes, AVR-Pita and AVR-Pik respectively. We also found that AVR-Pita interacts with Pi-39(t) and Ptr, and Pi9 interacts with both AVR-Pi9 and AVR-Pik. Validation of direct interactions of two pairs of R and AVR proteins supported a direct interaction mechanism of plant innate immunity. Detecting interaction of both Ptr and Pi39(t) with AVR-Pita, and Pi-9 with both AVR-Pi9 and AVR-Pik, revealed a new insight into recognition of pathogen signaling molecules by these host R genes in triggering plant innate immunity.

molecular biology↗