Comparison of lipid profiles of male and female silkworm (Bombyx mori) pupae through high-resolution mass spectrometry-based lipidomics and chemometrics.

Silkworm (Bombyx mori) pupae lipid profiles were analyzed using high-resolution mass spectrometry-based lipidomics. A total of 241 lipid molecular species were annotated with high confidence in male and female silkworm pupae. Triacylglycerol (TG), phosphoethanolamine (PE) and phosphocholine (PC) were the main lipid subclasses of silkworm pupae, accounting for 63, 41 and 38 lipid molecular species, respectively. No unique lipid molecular species were identified, but there were differences in the abundance of lipid molecular species between male and female silkworm pupae. Therefore, the differences in the lipid abundance of male and female silkworm pupae were analyzed by chemometrics. As a result, 8 lipid molecular species were screened for differential lipids. Hierarchical clustering analysis (HCA) showed that male and female silkworm pupae samples formed two distinct branches, indicating that these differential lipids could potentially be used as biomarkers to distinguish between male and female silkworm pupae.

Quantitative proteomics reveals insights into the assembly of IFT trains and ciliary assembly.

Intraflagellar transport (IFT) is required for ciliary assembly. The IFT machinery comprises the IFT motors kinesin-2 and IFT dynein plus IFT-A and IFT-B complexes, which assemble into IFT trains in cilia. To gain mechanistic understanding of IFT and ciliary assembly, here, we performed an absolute quantification of IFT machinery in Chlamydomonas reinhardtii cilium. There are ∼756, ∼532, ∼276 and ∼350 molecules of IFT-B, IFT-A, IFT dynein and kinesin-2, respectively, per cilium. The amount of IFT-B is sufficient to sustain rapid ciliary growth in terms of tubulin delivery. The stoichiometric ratio of IFT-B:IFT-A:dynein is ∼3:2:1 whereas the IFT-B:IFT-A ratio in an IFT dynein mutant is 2:1, suggesting that there is a plastic interaction between IFT-A and IFT-B that can be influenced by IFT dynein. Considering diffusion of kinesin-2 during retrograde IFT, it is estimated that one kinesin-2 molecule drives eight molecules of IFT-B during anterograde IFT. These data provide new insights into the assembly of IFT trains and ciliary assembly.

KLF12 interacts with TRIM27 to affect cisplatin resistance and cancer metastasis in esophageal squamous cell carcinoma by regulating L1CAM expression.

Krüppel-like factor 12 (KLF12) has been characterized as a transcriptional repressor, and previous studies have unveiled its roles in angiogenesis, neural tube defect, and natural killer (NK) cell proliferation. However, the contribution of KLF12 to cancer treatment remains undefined. Here, we show that KLF12 is downregulated in various cancer types, and KLF12 downregulation promotes cisplatin resistance and cancer metastasis in esophageal squamous cell carcinoma (ESCC). Mechanistically, KLF12 binds to the promoters of L1 Cell Adhesion Molecule (L1CAM) and represses its expression. Depletion of L1CAM abrogates cisplatin resistance and cancer metastasis caused by KLF12 loss. Moreover, the E3 ubiquitin ligase tripartite motif-containing 27 (TRIM27) binds to the N-terminal region of KLF12 and ubiquitinates KLF12 at K326 via K33-linked polyubiquitination. Notably, TRIM27 depletion enhances the transcriptional activity of KLF12 and consequently inhibits L1CAM expression. Overall, our study elucidated a novel regulatory mechanism involving TRIM27, KLF12 and L1CAM, which plays a substantial role in cisplatin resistance and cancer metastasis in ESCC. Targeting these genes could be a promising approach for ESCC treatment.

Atomically Precise Nanometer-Sized Pt Catalysts with an Additional Photothermy Functionality.

Atomically precise ~1-nm Pt nanoparticles (nanoclusters, NCs) with ambient stability are important in fundamental research and exhibit diverse practical applications (catalysis, biomedicine, etc.). However, synthesizing such materials is challenging. Herein, by employing the mixture ligand protecting strategy, we successfully synthesized the largest organic-ligand-protected (~1-nm) Pt23 NCs precisely characterized with mass spectrometry and single-crystal X-ray diffraction analyses. Interestingly, natural population analysis and Bader charge calculation indicate an alternate, varying charge -layer distribution in the sandwich-like Pt23 NC kernel. Pt23 NCs can catalyze the oxygen reduction reaction under acidic conditions without requiring calcination and other treatments, and the resulting specific and mass activities without further treatment are sevenfold and eightfold higher than those observed for commercial Pt/C catalysts, respectively. Density functional theory and d-band center calculations interpret the high activity. Furthermore, Pt23 NCs exhibit a photothermal conversion efficiency of 68.4 % under 532-nm laser irradiation and can be used at least for six cycles, thus demonstrating great potential for practical applications.

Nuclear RNA homeostasis promotes systems-level coordination of cell fate and senescence.

Understanding cellular coordination remains a challenge despite knowledge of individual pathways. The RNA exosome, targeting a wide range of RNA substrates, is often downregulated in cellular senescence. Utilizing an auxin-inducible system, we observed that RNA exosome depletion in embryonic stem cells significantly affects the transcriptome and proteome, causing pluripotency loss and pre-senescence onset. Mechanistically, exosome depletion triggers acute nuclear RNA aggregation, disrupting nuclear RNA-protein equilibrium. This disturbance limits nuclear protein availability and hinders polymerase initiation and engagement, reducing gene transcription. Concurrently, it promptly disrupts nucleolar transcription, ribosomal processes, and nuclear exporting, resulting in a translational shutdown. Prolonged exosome depletion induces nuclear structural changes resembling senescent cells, including aberrant chromatin compaction, chromocenter disassembly, and intensified heterochromatic foci. These effects suggest that the dynamic turnover of nuclear RNA orchestrates crosstalk between essential processes to optimize cellular function. Disruptions in nuclear RNA homeostasis result in systemic functional decline, altering the cell state and promoting senescence.

Supplementation of nicotinamide mononucleotide diminishes COX-2 associated inflammatory responses in macrophages by activating kynurenine/AhR signaling.

Cyclooxygenase-2 (COX-2) is an inducible enzyme responsible for prostaglandin synthesis during inflammation and immune responses. Our previous results show that NAD+ level decreased in activated macrophages while nicotinamide mononucleotide (NMN) supplementation suppressed the inflammatory responses via restoring NAD+ level and downregulating COX-2. However, whether NMN downregulates COX-2 in mouse model of inflammation, and its underlying mechanism needs to be further explored. In the present study, we established LPS- and alum-induced inflammation model and demonstrated that NMN suppressed the inflammatory responses in vivo. Quantitative proteomics in mouse peritoneal macrophages identified that NMN activated AhR signaling pathway in activated macrophages. Furthermore, we revealed that NMN supplementation led to IDO1 activation and kynurenine accumulation, which caused AhR nuclear translocation and activation. On the other hand, AhR or IDO1 knockout abolished the effects of NMN on suppressing COX-2 expression and inflammatory responses in macrophages. In summary, our results demonstrated that NMN suppresses inflammatory responses by activating IDO-kynurenine-AhR pathway, and suggested that administration of NMN in early-stage immuno-activation may cause an adverse health effect.

HER2 phosphorylation induced by TGF-ß promotes mammary morphogenesis and breast cancer progression.

Transforming growth factor ß (TGF-ß) and HER2 signaling collaborate to promote breast cancer progression. However, their molecular interplay is largely unclear. TGF-ß can activate mitogen-activated protein kinase (MAPK) and AKT, but the underlying mechanism is not fully understood. In this study, we report that TGF-ß enhances HER2 activation, leading to the activation of MAPK and AKT. This process depends on the TGF-ß type I receptor TßRI kinase activity. TßRI phosphorylates HER2 at Ser779, promoting Y1248 phosphorylation and HER2 activation. Mice with HER2 S779A mutation display impaired mammary morphogenesis, reduced ductal elongation, and branching. Furthermore, wild-type HER2, but not S779A mutant, promotes TGF-ß-induced epithelial-mesenchymal transition, cell migration, and lung metastasis of breast cells. Increased HER2 S779 phosphorylation is observed in human breast cancers and positively correlated with the activation of HER2, MAPK, and AKT. Our findings demonstrate the crucial role of TGF-ß-induced S779 phosphorylation in HER2 activation, mammary gland development, and the pro-oncogenic function of TGF-ß in breast cancer progression.

Controlled Sequential Doping of Metal Nanocluster.

Atomically precise doping of metal nanoclusters provides excellent opportunities not only for subtly tailoring their properties but also for in-depth understanding of composition (structure)-property correlation of metal nanoclusters and has attracted increasing interest partly due to its significance for fundamental research and practical applications. Although single and multiple metal atom doping of metal nanoclusters (NCs) has been achieved, sequential single-to-multiple metal atom doping is still a big challenge and has not yet been reported. Herein, by introducing a second ligand, a novel multistep synthesis method was developed, controlled sequential single-to-multiple metal atom doping was successfully achieved for the first time, and three doped NCs Au25Cd1(p-MBT)17(PPh3)2, Au18Cd2(p-MBT)14(PPh3)2, and [Au19Cd3(p-MBT)18]- (p-MBTH: para-methylbenzenethiol) were obtained, including two novel NCs that were precisely characterized via mass spectrometry, single-crystal X-ray crystallography, and so forth. Furthermore, sequential doping-induced evolutions in the atomic and crystallographic structures and optical and catalytic properties of NCs were revealed.

Flavonoid 4,4'-dimethoxychalcone selectively eliminates senescent cells via activating ferritinophagy.

Flavonoids are bioactive natural polyphenolic compounds with health benefits, including anti-tumor, anti-inflammatory and anti-aging effects. Our previous studies revealed that a flavonoid 4,4'-dimethoxychalcone (DMC) induced ferroptosis via inhibiting ferrochelatase (FECH). However, the effect of DMC on cellular senescence is unknown. In the present study, we found that DMC treatment selectively eliminated senescent cells, and DMC alone or a combination of DMC and quercetin or dasatinib showed high efficiency in the clearance of senescent cells. We identified FECH was highly expressed in senescent cells compared to non-senescent cells. Mechanistically, we found that DMC inhibited FECH and induced ferritinophagy, which led to an increase of labile iron pool, triggering ferroptosis of senescent cells. Importantly, we found that DMC treatment prevented hair loss, improved motor coordination, and reduced the expression of several senescence-associated secretory phenotype factors (IL-6, IL-1ß, CXCL-10, and MMP12) in the liver of old mice. Collectively, we revealed that, through the induction of ferroptosis, DMC holds the promise as a new senolytics to prevent age-related pathologies.

Age-related noncanonical TRMT6-TRMT61A signaling impairs hematopoietic stem cells.

Aged hematopoietic stem cells (HSCs) exhibit compromised reconstitution capacity and differentiation bias toward myeloid lineages. However, the molecular mechanism behind HSC aging remains largely unknown. In this study, we observed that RNA N1-methyladenosine-generating methyltransferase TRMT6-TRMT61A complex is increased in aged murine HSCs due to aging-declined CRL4DCAF1-mediated ubiquitination degradation signaling. Unexpectedly, no difference of tRNA N1-methyladenosine methylome is observed between young and aged hematopoietic stem and progenitor cells, suggesting a noncanonical role of the TRMT6-TRMT61A complex in the HSC aging process. Further investigation revealed that enforced TRMT6-TRMT61A impairs HSCs through 3'-tiRNA-Leu-CAG and subsequent RIPK1-RIPK3-MLKL-mediated necroptosis cascade. Deficiency of necroptosis ameliorates the self-renewal capacity of HSCs and counters the physiologically deleterious effect of enforced TRMT6-TRMT61A on HSCs. Together, our work uncovers a nonclassical role for the TRMT6-TRMT61A complex in HSC aging and highlights a therapeutic target.

MCT1-governed pyruvate metabolism is essential for antibody class-switch recombination through H3K27 acetylation.

Monocarboxylate transporter 1 (MCT1) exhibits essential roles in cellular metabolism and energy supply. Although MCT1 is highly expressed in activated B cells, it is not clear how MCT1-governed monocarboxylates transportation is functionally coupled to antibody production during the glucose metabolism. Here, we report that B cell-lineage deficiency of MCT1 significantly influences the class-switch recombination (CSR), rendering impaired IgG antibody responses in Mct1f/fMb1Cre mice after immunization. Metabolic flux reveals that glucose metabolism is significantly reprogrammed from glycolysis to oxidative phosphorylation in Mct1-deficient B cells upon activation. Consistently, activation-induced cytidine deaminase (AID), is severely suppressed in Mct1-deficient B cells due to the decreased level of pyruvate metabolite. Mechanistically, MCT1 is required to maintain the optimal concentration of pyruvate to secure the sufficient acetylation of H3K27 for the elevated transcription of AID in activated B cells. Clinically, we found that MCT1 expression levels are significantly upregulated in systemic lupus erythematosus patients, and Mct1 deficiency can alleviate the symptoms of bm12-induced murine lupus model. Collectively, these results demonstrate that MCT1-mediated pyruvate metabolism is required for IgG antibody CSR through an epigenetic dependent AID transcription, revealing MCT1 as a potential target for vaccine development and SLE disease treatment.

Dual-Specificity Inhibitor Targets Enzymes of the Trehalose Biosynthesis Pathway.

To reduce the risk of resistance development, a novel fungicide with dual specificity is demanded. Trehalose is absent in animals, and its synthases, trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP), are safe fungicide targets. Here, we report the discovery of a dual-specificity inhibitor of MoTps1 (Magnaporthe oryzae Tps1, TPS) and MoTps2 (M. oryzae Tps2, TPP). The inhibitor, named A1-4, was obtained from a virtual screening and subsequent surface plasmon resonance screening. In in vitro assays, A1-4 interacts with MoTps1 and MoTps2-TPP (MoTps2 TPP domain) and inhibits their enzyme activities. In biological activity assays, A1-4 not only inhibits the virulence of M. oryzae on host but also causes aggregation of conidia cytosol, which is a characteristic phenotype of MoTps2. Furthermore, hydrogen/deuterium exchange mass spectrometry assays support the notion that A1-4 binds to the substrate pockets of TPS and TPP. Collectively, A1-4 is a promising hit compound for the development of safe fungicide with dual-target specificity.

HMGN2 and Histone H1.2: potential targets of a novel probiotic mixture for seasonal allergic rhinitis.

Background: Allergic rhinitis (AR) is a common nasal inflammatory disorder that severely affects an individual's quality of life (QoL) and poses a heavy financial burden. In addition to routine treatments, probiotic intervention has emerged as a promising strategy for preventing and alleviating allergic diseases. The main objective of this study was to determine the effect of a novel multi-strain probiotic mixture on AR symptoms and investigate potential targets underlying the probiotic intervention. Methods: A randomized, double-blind, placebo-controlled clinical study was conducted on AR patients who were allergic to autumnal pollens (n = 31). Placebo or a novel probiotic mixture, composed of Lactobacillus rhamnosus (L. rhamnosus) HN001, L. acidophilus NCFM, Bifidobacterium lactis (B. lactis) Bi-07, L. paracasei LPC-37, and L. reuteri LE16, was administered after 2 months. The therapeutic efficacy was evaluated by a symptom assessment scale. Before and during the pollen season, blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were isolated for further tandem mass tags (TMTs)-based quantitative proteomic analyses. Potential targets and underlying pathological pathways were explored using bioinformatics methods. Results: During the pollen season, the rhinoconjunctivitis symptom score of participants who were administered probiotics (probiotic group, n = 15) was significantly lower than those administered placebo (placebo group, n = 15) (P = 0.037). The proteomic analyses identified 60 differentially expressed proteins (DEPs) in the placebo group, and subsequent enrichment analyses enriched a series of pathways and biological processes, including signaling pathways of inflammation, coagulation cascade, lipid, carbohydrate and amino acid metabolic pathways, and transcription and translation processes. Least Absolute Shrinkage and Selection Operator (LASSO) regression extracted five main elements, namely, GSTO1, ATP2A2, MCM7, PROS1, and TRIM58, as signature proteins. A total of 17 DEPs were identified in the probiotic group, and there was no pathway enriched. Comparison of DEPs in the two groups revealed that the expression levels of the high-mobility group nucleosome-binding domain-containing protein 2 (HMGN2) and Histone H1.2 presented an opposite trend with different interventions. Conclusion: Our data showed that AR symptoms alleviated after treatment with the novel multi-strain probiotic mixture, and the proteomic analyses suggested that HMGN2 and Histone H1.2 might be targets of probiotic intervention for seasonal AR.

Structural basis for recruitment of TASL by SLC15A4 in human endolysosomal TLR signaling.

Toll-like receptors (TLRs) are a class of proteins that play critical roles in recognizing pathogens and initiating innate immune responses. TASL, a recently identified innate immune adaptor protein for endolysosomal TLR7/8/9 signaling, is recruited by the lysosomal proton-coupled amino-acid transporter SLC15A4, and then activates IRF5, which in turn triggers the transcription of type I interferons and cytokines. Here, we report three cryo-electron microscopy (cryo-EM) structures of human SLC15A4 in the apo monomeric and dimeric state and as a TASL-bound complex. The apo forms are in an outward-facing conformation, with the dimeric form showing an extensive interface involving four cholesterol molecules. The structure of the TASL-bound complex reveals an unprecedented interaction mode with solute carriers. During the recruitment of TASL, SLC15A4 undergoes a conformational change from an outward-facing, lysosomal lumen-exposed state to an inward-facing state to form a binding pocket, allowing the N-terminal helix of TASL to be inserted into. Our findings provide insights into the molecular basis of regulatory switch involving a human solute carrier and offers an important framework for structure-guided drug discovery targeting SLC15A4-TASL-related human autoimmune diseases.

Molecular basis of methyl-salicylate-mediated plant airborne defence.

Aphids transmit viruses and are destructive crop pests1. Plants that have been attacked by aphids release volatile compounds to elicit airborne defence (AD) in neighbouring plants2-5. However, the mechanism underlying AD is unclear. Here we reveal that methyl-salicylate (MeSA), salicylic acid-binding protein-2 (SABP2), the transcription factor NAC2 and salicylic acid-carboxylmethyltransferase-1 (SAMT1) form a signalling circuit to mediate AD against aphids and viruses. Airborne MeSA is perceived and converted into salicylic acid by SABP2 in neighbouring plants. Salicylic acid then causes a signal transduction cascade to activate the NAC2-SAMT1 module for MeSA biosynthesis to induce plant anti-aphid immunity and reduce virus transmission. To counteract this, some aphid-transmitted viruses encode helicase-containing proteins to suppress AD by interacting with NAC2 to subcellularly relocalize and destabilize NAC2. As a consequence, plants become less repellent to aphids, and more suitable for aphid survival, infestation and viral transmission. Our findings uncover the mechanistic basis of AD and an aphid-virus co-evolutionary mutualism, demonstrating AD as a potential bioinspired strategy to control aphids and viruses.

Oxidized galectin-1 in SLE fails to bind the inhibitory receptor VSTM1 and increases reactive oxygen species levels in neutrophils.

Inhibitory immune receptors set thresholds for immune cell activation, and their deficiency predisposes a person to autoimmune responses. However, the agonists of inhibitory immune receptors remain largely unknown, representing untapped sources of treatments for autoimmune diseases. Here, we show that V-set and transmembrane domain-containing 1 (VSTM1) is an inhibitory receptor and that its binding by the competent ligand soluble galectin-1 (Gal1) is essential for maintaining neutrophil viability mediated by downregulated reactive oxygen species production. However, in patients with systemic lupus erythematosus (SLE), circulating Gal1 is oxidized and cannot be recognized by VSTM1, leading to increased intracellular reactive oxygen species levels and reduced neutrophil viability. Dysregulated neutrophil function or death contributes significantly to the pathogenesis of SLE by providing danger molecules and autoantigens that drive the production of inflammatory cytokines and the activation of autoreactive lymphocytes. Interestingly, serum levels of glutathione, an antioxidant able to convert oxidized Gal1 to its reduced form, were negatively correlated with SLE disease activity. Taken together, our findings reveal failed inhibitory Gal1/VSTM1 pathway activation in patients with SLE and provide important insights for the development of effective targeted therapies.

Multi-Omics Analyses Reveal Mitochondrial Dysfunction Contributing to Temozolomide Resistance in Glioblastoma Cells.

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor with poor prognosis. Temozolomide (TMZ) is the standard chemotherapy for glioblastoma treatment, but TMZ resistance significantly compromises its efficacy. In the present study, we generated a TMZ-resistant cell line and identified that mitochondrial dysfunction was a novel factor contributing to TMZ resistance though multi-omics analyses and energy metabolism analysis. Furthermore, we found that rotenone treatment induced TMZ resistance to a certain level in glioblastoma cells. Notably, we further demonstrated that elevated Ca2+ levels and JNK-STAT3 pathway activation contributed to TMZ resistance and that inhibiting JNK or STAT3 increases susceptibility to TMZ. Taken together, our results indicate that co-administering TMZ with a JNK or STAT3 inhibitor holds promise as a potentially effective treatment for glioblastoma.

Global histone H2B degradation regulates insulin/IGF signaling-mediated nutrient stress.

Eukaryotic organisms adapt to environmental fluctuations by altering their epigenomic landscapes and transcriptional programs. Nucleosomal histones carry vital epigenetic information and regulate gene expression, yet the mechanisms underlying chromatin-bound histone exchange remain elusive. Here, we found that histone H2Bs are globally degraded in Caenorhabditis elegans during starvation. Our genetic screens identified mutations in ubiquitin and ubiquitin-related enzymes that block H2B degradation in starved animals, identifying lysine 31 as the crucial residue for chromatin-bound H2B ubiquitination and elimination. Retention of aberrant nucleosomal H2B increased the association of the FOXO transcription factor DAF-16 with chromatin, generating an ectopic gene expression profile detrimental to animal viability when insulin/IGF signaling was reduced in well-fed animals. Furthermore, we show that the ubiquitin-proteasome system regulates chromosomal histone turnover in human cells. During larval development, C. elegans epidermal cells undergo H2B turnover after fusing with the epithelial syncytium. Thus, histone degradation may be a widespread mechanism governing dynamic changes of the epigenome.

Lattice Compression Revealed at the ≈1†nm Scale.

Lattice tuning at the ≈1 nm scale is fascinating and challenging; for instance, lattice compression at such a minuscule scale has not been observed. The lattice compression might also bring about some unusual properties, which waits to be verified. Through ligand induction, we herein achieve the lattice compression in a ≈1 nm gold nanocluster for the first time, as detected by the single-crystal X-ray crystallography. In a freshly synthesized Au52 (CHT)28 (CHT=S-c-C6 H11 ) nanocluster, the lattice distance of the (110) facet is found to be compressed from 4.51 to 3.58 Šat the near end. However, the lattice distances of the (111) and (100) facets show no change in different positions. The lattice-compressed nanocluster exhibits superior electrocatalytic activity for the CO2 reduction reaction (CO2 RR) compared to that exhibited by the same-sized Au52 (TBBT)32 (TBBT=4-tert-butyl-benzenethiolate) nanocluster and larger Au nanocrystals without lattice variation, indicating that lattice tuning is an efficient method for tailoring the properties of metal nanoclusters. Further theoretical calculations explain the high CO2 RR performance of the lattice-compressed Au52 (CHT)28 and provide a correlation between its structure and catalytic activity.

Comparative Lysine Acetylome Analysis of Y. pestis YfiQ/CobB Mutants Reveals that Acetylation of SlyA Lys73 Significantly Promotes Biofilm Formation of Y. pestis.

Increasing evidence shows that protein lysine acetylation is involved in almost every aspect of cellular physiology in bacteria. Yersinia pestis is a flea-borne pathogen responsible for millions of human deaths in three global pandemics. However, the functional role of lysine acetylation in this pathogen remains unclear. Here, we found more acetylated proteins and a higher degree of acetylation in Y. pestis grown under mammalian host (Mh) conditions than under flea vector (Fv) conditions, suggesting that protein acetylation could significantly change during fleabite transmission. Comparative acetylome analysis of mutants of YfiQ and CobB, the major acetyltransferase and deacetylase of Y. pestis, respectively, identified 23 YfiQ-dependent and 315 CobB-dependent acetylated proteins. Further results demonstrated that acetylation of Lys73 of the SlyA protein, a MarR-family transcriptional regulator, inhibits its binding to the promoter of target genes, including hmsT that encodes diguanylate cyclase responsible for the synthesis of c-di-GMP, and significantly enhances biofilm formation of Y. pestis. Our study presents the first extensive acetylome data of Y. pestis and a critical resource for the functional study of lysine acetylation in this pathogen. IMPORTANCE Yersinia pestis is the etiological agent of plague, historically responsible for three global pandemics. The 2017 plague epidemic in Madagascar was a reminder that Y. pestis remains a real threat in many parts of the world. Plague is a zoonotic disease that primarily infects rodents via fleabite, and transmission of Y. pestis from infected fleas to mammals requires rapid adaptive responses to adverse host environments to establish infection. Our study provides the first global profiling of lysine acetylation derived from mass spectrometry analysis in Y. pestis. Our data set can serve as a critical resource for the functional study of lysine acetylation in Y. pestis and provides new molecular insight into the physiological role of lysine acetylation in proteins. More importantly, we found that acetylation of Lys73 of SlyA significantly promotes biofilm formation of Y. pestis, indicating that bacteria can use lysine acetylation to fine-tune the expression of genes to improve adaptation.