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Fu, J.

Publications and source records attributed to Fu, J..

At least 55 records · Page 3Linked to original sources

Robust Production of Parvalbumin Cortical Interneurons and Fast-Spiking Neurons from Human Medial Ganglionic Eminence Organoids

The medial ganglionic eminence (MGE) gives rise to parvalbumin (PV)-and somatostatin (SST)-expressing cortical interneurons essential for regulating cortical excitability. Although PV interneurons are linked to various neurodevelopmental and neurodegenerative disorders, reliably generating them from human pluripotent stem cells (hPSCs) has been extremely challenging. We present a robust, reproducible protocol for generating single-rosette MGE organoids (MGEOs) from hPSCs. Transcriptomic analyses reveal that MGEOs exhibit MGE regional identity and faithfully model the developing human fetal MGE. As MGEOs mature, they generate abundant PV-expressing cortical interneurons, including putative basket and axoaxonic cells, at a scale not previously achieved in vitro. When fused with human cortical organoids (hCOs), these interneurons rapidly migrate into the hCOs, integrate into excitatory networks, and contribute to complex electrophysiological patterns and the emergence of large numbers of fast-spiking neurons. Using this model, we uncover a previously unreported migration deficit of MGE interneurons in a disease model of SLC6A1 developmental and epileptic encephalopathy, offering potential insights into the developmental contributions to epileptogenesis. MGEOs thus offer a powerful in vitro approach for probing human MGE-lineage cortical and subcortical GABAergic neuron development, modeling various neuropsychiatric disorders, and advancing cell-based therapies for neurodevelopmental and neurodegenerative disorders. HighlightsO_LIGeneration of subpallial organoids highly enriched for MGE lineages C_LIO_LIMGE organoids (MGEOs) robustly produce parvalbumin-expressing cortical interneurons C_LIO_LIComplex network activity and fast-spiking neurons are generated in assembloids C_LIO_LIImpaired interneuron migration in SLC6A1 knockout and patient-derived MGEOs C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/662594v2_ufig1.gif" ALT="Figure 1"> View larger version (69K): org.highwire.dtl.DTLVardef@1fce574org.highwire.dtl.DTLVardef@3c28d2org.highwire.dtl.DTLVardef@19bf737org.highwire.dtl.DTLVardef@834f2b_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

The histidine kinase NahK in Pseudomonas aeruginosa is essential for nitric oxide-stress resistance in nutrient starved media

Biofilms are communities of bacteria growing within a matrix composed of polymeric substances that act as a barrier to antimicrobials, making bacteria within a biofilm recalcitrant to conventional antibiotic treatments. This lifestyle of bacteria is especially relevant during its pathogenesis, as observed in the case of Pseudomonas aeruginosa infections of immunocompromised patients. However, pico- to nanomolar concentrations of nitric oxide (NO) have been shown to be efficient in triggering P. aeruginosa to disperse from biofilms, suggesting that a combination of NO exposure and antibiotic treatment may help in mitigating infections. In P. aeruginosa, the NosP-NahK two component system, which comprises a NO sensing hemoprotein, NosP, and its associated hybrid histidine kinase, NahK, has been proven to be necessary for NO mediated biofilm dispersal. NahK also has additional roles in biofilm formation, motility, denitrification and virulence, due to its regulation of a global post-transcriptional regulator RsmA. Here, we uncover a novel role of NahK in enhancing the resistance of P. aeruginosa to signaling concentrations of NO. Deletion of nahK sensitizes the strain to nanomolar levels of NO, resulting in DNA damage. Consequently, the SOS stress response pathway is induced, which causes phenotypes such as cell filamentation and cell clustering due to lysis-mediated release of extracellular DNA. Our data also indicate that increased susceptibility of the {Delta}nahK strain to NO is due to the antagonization of RsmA, and is restricted to amino acid starved media, suggesting that NahK may also have previously unappreciated roles in modulating amino acid metabolism. ImportanceP. aeruginosa infections of cystic fibrosis patients can result in increased risk of fatality, necessitating the development of better therapeutic strategies to treat its infections. Here, we present data suggesting that nanomolar concentrations of NO, that are normally used to disperse P. aeruginosa from biofilms, can also sensitize the bacterium to NO mediated DNA damage upon loss of function of the histidine kinase NahK. The resulting SOS stress response may benefit the bacterium through favorable mutations but also poses a risk due to SOS-associated pyocin production through cell lysis. Hence, understanding the molecular mechanisms underlying NahK mediated resistance to NO is important to leverage this regulation and identify novel targets to treat P. aeruginosa infections.

microbiology↗

Protein Folding accompanied by disulfide bond formation drives glutenin polymerization into multidimensional gluten networks

Wheat flour dough, which is routinely used to make bread, pasta and noodles, can be stretched several thousand-fold without rupture. The molecular basis of this extraordinary property arises due to the ability to crosslink glutenin subunits, the major constituent of dough, into linear and branched elastic networks. The mechanism by which the glutenin subunits self-assemble and polymerize is unknown. Here, we show, using mass spectrometry, confocal imaging and molecular dynamics simulations that structuring of two hydrophobic residues, phenylalanine and tyrosine, in the core region of the monomeric glutenin 1Dx5 N-terminal domain (1Dx5-NTD) initiates inter molecular interactions and network formation. Upon folding of monomeric 1Dx5-NTD, two cysteine residues (Cys10 and Cys40) form an intramolecular disulfide bond and poises the third cysteine (Cys25) to engage in inter molecular crosslink with other glutenin subunits. Propagation of such a disulfide linkage pattern results in the formation of a cohesive linear gluten network. In alternate pathways, crosslinking of Cys10 with Cys25 with a third glutenin subunit results in the creation of a junction, which drives the formation of a three-dimensional network. The disulfide patterns in the networks accord well with the measured chemical reactivity of each cysteine residue and the solvent accessibility of the associated side chains during 1Dx5-NTD interactions. Our study shows that the diversity in the folding of a single glutenin subunit that exposes the third cysteine to the solvent is the key event that initiates polymerization and directs the formation of networks with differing architecture. Significance statementGlutenin proteins polymerize to form intricate molecular networks that support the expansion of dough by several thousand-fold. Although network formation occurs spontaneously, the polymerization mechanism is unknown. There are multiple cysteine residues in glutenin that can form intra and intermolecular disulfide bonds. Multiple experimental techniques and molecular dynamics simulations are used to show that folding of glutenin, initiated by two hydrophobic residues, exposes cysteines that are poised to form intermolecular disulfide bonds. The disulfide crosslinking pattern, determined by the initial folding process, dictates the creation of a linear or branched network. The study demonstrates that the propensity to form linear or branched networks is encoded by the diversity of the disulfide patterns created at the level of monomeric folding.

biophysics↗

Bifidobacterium longum subsp. nexus nov., a novel subspecies isolated from infant stool

Bifidobacterium longum is a foundational, genetically diverse member of the infant gut microbiome, yet resolving its subspecies in metagenomic data remains challenging. Here, we performed a deep phylogenetic characterization of the B. longum species utilizing 4,577 fecal metagenomes from the LLNEXT mother-infant cohort alongside a global dataset of 1,220 genomes and metagenome-assembled genomes (MAGs). We identified a novel, geographically widespread lineage: Bifidobacterium longum subsp. nexti. Using a polyphasic taxonomic analysis, including average nucleotide identity and digital DNA-DNA hybridization, confirms subspecies-level divergence. Distinct from other members of the B. longum species, BL. nexti harbors -amylopullulanase and grows on soluble starch and often pullulan, consistent with -glucan utilization. Within the LLNEXT cohort, BL. nexti is enriched in formula-fed infants and shows evidence consistent with vertical transmission. Globally, while BL. nexti is geographically widespread, it usually persists at low relative abundance across diverse populations. By resolving a major fraction of previously unclassified B. longum diversity, this study provides new insights into the specialized lineages and ecological dynamics driving the assembly of the developing infant microbiome.

microbiology↗

Targeting HMGA1-driven leukemic transformation in myeloproliferative neoplasms with pacritinib

Progression of myeloproliferative neoplasms (MPNs) to secondary acute myeloid leukemia (sAML) is a lethal transition lacking reliable early biomarkers and effective therapies. Integrating multi-omics analyses, a cohort of 240 patient biopsies, and functional studies, we identify High Mobility Group A1 (HMGA1) as a critical driver and predictor of this transformation. HMGA1 expression, readily detectable by immunohistochemistry, progressively increases from chronic MPN phases to sAML, outperforming established markers (CD34/CD117) in predicting impending leukemic transformation (AUC = 0.96). Mechanistically, HMGA1 cooperates with JAK2V617F and TP53 mutations to promote leukemogenesis. Clinically, high HMGA1 levels correlate with resistance to first-generation JAK inhibitors and portend poor overall survival. Importantly, the next generation JAK2/FLT3 inhibitor pacritinib abrogates HMGA1-driven proliferation and significantly extends survival in preclinical models, offering an immediate therapeutic strategy for this high-risk population. Our findings establish HMGA1 as an actionable biomarker for risk stratification and early intervention, and a therapeutic target to overcome therapeutic resistance in MPN-sAML. HighlightsO_LIHMGA1 IHC staining serves as a readily implementable biomarker, outperforming existing marker for early prediction of MPN progression to sAML and identifying patients at high risk. C_LIO_LIElevated HMGA1 expression correlates with resistance to first-generation JAK inhibitors and predicts poor overall survival in MPN-sAML patients, highlighting a critical unmet therapeutic need. C_LIO_LIThe next-generation JAK2 inhibitor pacritinib effectively overcomes HMGA1-driven aggressive disease and therapy resistance, offering a rational, clinically available treatment strategy for HMGA1-high MPN-sAML. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/657170v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@18b835org.highwire.dtl.DTLVardef@e5b31dorg.highwire.dtl.DTLVardef@5245caorg.highwire.dtl.DTLVardef@163f5de_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Stage-resolved gene regulatory network analysis reveals developmental reprogramming and genes with robust stem-preferred expression in sorghum

BackgroundSorghum bicolor is a deep-rooted, heat- and drought-tolerant crop that thrives on marginal lands and is increasingly valued for its applications in biofuel, bioenergy, and biopolymer production. The sorghum stem, which can reach 4-5 meters in length, serves as the primary reservoir of both lignocellulosic biomass and soluble sugars, making it a promising bioenergy feedstock. Although recent advances in genetic, genomic, and transcriptomic resources have improved our understanding of sorghum biology, comprehensive genome-wide analyses of functional dynamics across diverse organ types and developmental stages remain limited. In particular, candidate genes with stem preferred expression pattern or their associated cis-regulatory elements, which may program key stem-related functions and enable organ- or tissue-specific engineering, have not yet been identified. ResultsTo address these gaps, we reanalyzed a published RNA-seq dataset to identify genes with organ-preferential expression and to infer representative organ functions across major developmental stages. Our analysis revealed that the sorghum stem exhibits distinct temporal functional signatures, which correlate with the developmental dynamics of stem-specific genes and their associated regulatory elements. We further identified a set of genes with ubiquitous stem-specific expression across diverse sorghum genotypes, suggesting their universal importance and broad potential for genetic engineering applications. Among them, SbTALE03 and SbTALE04 emerged as stem hub transcription factors (TF). Both genes were empirically validated for their stem specificity across stages. Gene regulatory network analysis further indicated that these TFs participate in stage-specific transcriptional programs that maintain and regulate stem development. ConclusionsThis study presents a genome-wide analysis of organ-specific gene expression, functions, and regulatory networks in sorghum, with a focus on genes preferentially-expressed in stems and their promoter motifs. We identified a set of core stem-specific genes with ubiquitous expression across genotypes and developmental stages, including two experimentally validated transcription factors with potential roles in stem development. These findings offer valuable candidates for further functional characterization and genetic engineering aimed at improving sorghum stem biomass and composition.

plant biology↗

Expression and Characterization of SARS-CoV-2 Spike Protein in Thermothelomyces heterothallica C1

The COVID-19 pandemic demonstrated a pressing need for rapid, adaptive, and scalable manufacturing of vaccines and reagents. With the transition into an endemic disease and rising threats of other emerging pandemics, production of these biologicals requires a stable and sustainable supply chain and accessible distribution methods. In this study, we demonstrate the strength of an engineered filamentous fungal platform, Thermothelomyces heterothallica C1, for high volumetric productivity of the full-length spike glycoprotein. Spike protein produced in this system is highly thermostable and immunization of mice with spike made in C1 or mammalian platforms resulted in a similar humoral response. Additionally, it was shown that the native N-glycan profile can be redecorated with complex sialylated structures, if necessary, resulting in a more human-like glycan profile, without impacting binding characteristics as shown experimentally and in simulations. Through extensive physicochemical analysis, the C1 produced spike performs similarly to spike proteins produced in other commercially available systems. The data presented is evidence that C1 can be a strong platform for production of complex glycosylated recombinant proteins such as subunit antigen vaccines.

bioengineering↗

Whole-Proteome Screening and Multi-Modal Profiling of Antigen-Specific CD4+ T Cells at Single-Cell Resolution

Systematic whole-proteome screening and comprehensive profiling of antigen-specific CD4+ T cells are crucial for advancing our understanding of CD4+ T cell immunity, yet such efforts remain technically challenging. Here, we present a high-throughput platform that employs large-scale class II single-chain trimer libraries to detect antigen-specific CD4+ T cells, while simultaneously profiling their antigen specificity, TCR/{beta} sequences, MHC restriction, whole transcriptomes, and patient/timepoint origins at single-cell resolution. We benchmarked SCTs against conventional pMHCs and validated the SCT library-based approach in direct ex vivo identification of antigen-specific CD4+ T cells in healthy donors. We then applied the platform to screen the entire SARS-CoV-2 receptor-binding domain in a longitudinal patient cohort, identifying 2,188 antigen-specific CD4+ T cells and revealing key features that define antigen immunogenicity. Extending to cancer, we performed whole-proteome screening of HPV-16 E6/E7 for TCR repertoire profiling in a precancerous cohort, uncovering functional heterogeneity of HPV-specific TCRs. By integrating high-throughput antigen screening with high-dimensional, multi-modal cellular characterization, our approach offers an unprecedented window into CD4+ T cell immunity across diverse disease contexts and empowers the development of new therapies.

bioengineering↗

Gut Microbiota Dysbiosis and Short-chain Fatty Acid alterations in Pediatric New-Onset Type 1 diabetes with Ketoacidosis

ObjectiveDiabetic ketoacidosis (DKA) stands as the most common acute hyperglycaemic complication with a relatively high mortality rate among children diagnosed with type 1 diabetes (T1D). Previous studies have shed light on gut dysbiosis in newly-onset T1D children, but research targeting the gut microbiota and microbial metabolites in patients with DKA remains scarce. MethodsShotgun metagenomic analysis was conducted on fecal samples from 96 newly diagnosed T1D children, including 32 patients who presented with DKA upon admission. Short-chain fatty acids (SCFAs) were quantified using gas chromatography/mass spectrometry (GC/MS). Comparative analyses were performed on the gut microbiome and SCFA levels between DKA and non-DKA subgroups. ResultsGut microbiota composition differed between DKA and non-DKA groups. While alpha-diversity remained consistent, beta-diversity showed marked differences between the two groups, and the phyla Firmicutes and Bacteroidetes exhibited predominance in the DKA group. DKA was associated with increased potential pathogens and a significant depletion of SCFA-producing genera (Anaerobutyricum, Dialister, Ruminococcus, Roseburia, Dorea, and Butyricicoccus), accompanied by reduced SCFA levels. Further correlation analysis revealed strong associations between SCFAs, SCFA-producing microbiota, and disease severity indicators. Propionic acid and butyric acid mediated the association between SCFA-producing bacteria and DKA. ConclusionThis study first reported reductions in SCFAs and SCFA-producing bacteria in the fecal samples of T1D children at DKA onset. Our findings highlight SCFAs and their producers as protective biomarkers of DKA and suggest that targeting gut microbiota and SCFA metabolism may offer a potential therapeutic strategy for DKA. ImportanceWhile gut microbiota imbalances have been linked to type 1 diabetes (T1D), little is known about the role of gut microbes and their metabolites during acute diabetic ketoacidosis (DKA), an acute and life-threatening complication. This study examined the gut microbiome and levels of short-chain fatty acids (SCFAs) in fecal samples from children with new-onset T1D with and without DKA. DKA was characterized by distinct microbial signatures, including increased potential pathogens, a loss of beneficial SCFA-producing bacteria, and consistently lower SCFA levels. These changes closely correlated with indicators of disease severity, and further mediation analysis revealed the role of SCFAs in linking gut microbiota to DKA. These findings suggest that SCFAs and their producers may serve as protective markers for DKA, highlighting the potential of microbiome-based interventions to improve outcomes in children facing this critical complication.

microbiology↗

Chemical Compensation to Mechanical Loss in CellMechanosensation

Mammalian cells sense and respond to environmental changes using a complex and intelligent system that integrates chemical and mechanical signals. The transduction of mechanical cues into chemical changes modulates cell physiology, allowing a cell to adapt to its microenvironment. Understanding how the chemical and mechanical regulatory modules interact is crucial for elucidating mechanisms of mechanosensation and cellular homeostasis. In this study, we find that cells exhibit non-monotonic changes in cell volume and intracellular pH when subjected to physical stimuli and varying degrees of actomyosin cytoskeleton disruption. We discover that these non-monotonic responses are mediated by a chemical compensation mechanism, where the attenuation of actomyosin activity stimulates the activity of PI3K/Akt pathway. This, in turn, activates sodium-hydrogen exchanger 1 (NHE1), resulting in elevated intracellular pH and increased cell volume. Furthermore, we identify a competitive interaction between the PI3K/Akt and MAPK/ERK pathways - two major regulators of cell proliferation and motility. This competition modulates the chemical compensation based on the relative activities of these pathways. Our mathematical modeling reveals the network structure that is essential for establishing the non-monotonic response. Interestingly, this regulatory system is altered in HT1080 fibrosarcoma, highlighting a potential mechanistic divergence in cancer cells in contrast to their normal-like counterpart, such as NIH 3T3 and HFF-1 fibroblasts. Overall, our work reveals a compensatory mechanism between chemical and mechanical signals, providing a novel infrastructure to elucidate the integrated mechanochemical response to environmental stimuli.

biophysics↗

The first chromosomal-level genome assembly of an allotetraploid oyster

Tetraploid oysters are used to cross with diploids to produce triploid oysters that have become an important part of the oyster aquaculture industry worldwide. Although most tetraploid oysters are artificially induced autotetraploids, allotetraploids can be produced between closely related species, providing new opportunities for polyploid breeding and studying genome interactions. Using PacBio sequencing, Illumina sequencing, and high-throughput chromosome conformation capture scaffolding, we assembled the first high-quality genome assembly of an artificially induced allotetraploid between the Pacific oyster Crassostrea gigas and Portuguese oyster Crassostrea angulata. The assembled genome is 1.23 Gb, with a contig N50 of 2.56 Mb and a scaffold N50 of 57.22 Mb, and anchored to 20 chromosomes. The assembly contains 58,330 protein-coding genes, 98.34% of which are functionally annotated. The heterozygosity and the ratio of repetitive sequences is 5.50% and 46.43%, respectively. This chromosomal-level genome assembly of an allotetraploid oyster provides a valuable genetic resource for studying genome biology of molluscs and for advanced breeding of polyploids that are critical for the oyster aquaculture industry.

genomics↗

Calcium starvation leads to strain-specific gene regulation of lipid and carotenoid production in Mucor Circinelloides

AO_SCPLOWBSTRACTC_SCPLOWFungi are pivotal in transitioning to a bio-based, circular economy due to their ability to transform organic material into valuable products such as organic acids, enzymes, and drugs. Mucor circinelloides is a model organism for studying lipogenesis and it particularly promising for its metabolic capabilities in producing oils like TAGs and carotenoids, influenced by environmental factors such as nutrient availability. Notably, strains VI04473 and FRR5020 have been identified for their potential in producing single-cell oils and carotenoids, respectively. Calcium starvation have previously been shown to have strain-specific effects, with VI04473 accumulating more lipids and FRR5020 producing more carotenoids. Here we used genome sequencing, comparative genomics, transcriptomics, and metabolite phenotyping to explore the genetic basis of lipid and carotenoid production under calcium starvation in these strains. We found extensive genomic rearrangements between these strains, as well as low conservation of gene regulatory responses to calcium depletion. This lack of conservation also applies to genes involved in lipid and carotenoid production, i.e. the lipidome. Several pathways show divergent regulation between strains, which explains the phenotypic divergence between VI04473 and FRR5020. The complex gene family evolution of several lipidome genes probably also affected specialization of these strains to calcium stress. Our study sheds light on the complexity of the evolution of metabolic networks in M. circinelloides. Understanding these genetic underpinnings can optimize the industrial use of M. circinelloides, enhancing lipid productivity and stress tolerance, and tailoring metabolic profiles for specific applications. This research advances our knowledge on complexity of fungal lipid metabolism and the role of calcium in regulating metabolic pathways.

genomics↗

A non-catalytic role for MLL2 in controlling chromatin organisation and mobility during the priming of pluripotent cells for differentiation

How the chromatin regulator MLL2 (KMT2B) influences cell differentiation remains poorly understood. MLL2 is the main histone 3 lysine 4 (H3K4) trimethyltransferase acting at bivalent promoters in embryonic stem cells (ESCs) and is required for ESCs to differentiate into neuroectoderm. We show here that this requirement occurs during exit from naive pluripotency, days before neuroectoderm differentiation is impaired. Although MLL2 knockout has only a subtle effect on transcription during exit, reducing the expression of a few important neuroectodermal transcription factors, it substantially remodels chromatin architecture, disrupting 3D chromatin loops associated with bivalent promoters. The enzymatic activity of MLL2 is not needed for stabilising these loops or for neuroectoderm differentiation. This non-catalytic function of MLL2 in stabilising 3D chromatin loops has implications for lineage specification. Because MLL2 shares features with all four MLLs, chromatin tethering, rather than H3K4 methylation, may represent the primary function of MLL proteins during lineage commitment.

cell biology↗

Epigenetic dysregulation of metabolic programs mediates liposarcoma cell plasticity

Sarcomas are rare connective tissue cancers thought to arise from aberrant mesenchymal stem cell (MSC) differentiation. Liposarcoma (LPS) holds valuable insights into dysfunctional differentiation given its well- and dedifferentiated histologic subtypes (WDLPS, DDLPS). Despite well-established differences in histology and clinical behavior, the molecular pathways underlying each subtype are poorly understood. Here, we performed single-nucleus multiome sequencing and spatial profiling on carefully curated human LPS samples and found defects in adipocyte-specific differentiation within LPS. Loss of insulin-like growth factor 1 (IGF1) and gain of cellular programs related to early mesenchymal development and glucagon-like peptide-1 (GLP-1)-induced insulin secretion are primary features of DDLPS. IGF1 loss was associated with worse overall survival in LPS patients. Through in vitro stimulation of the IGF1 pathway, we identified that DDLPS cells are deficient in the adipose-specific PPARG isoform 2 (PPARG2). Defects in IGF1/PPARG2 signaling in DDLPS led to a block in differentiation that could not be fully overcome with the addition of exogenous IGF1 or the pro-adipogenic agonists to PPARG and GLP-1. However, we noted upregulation of the IGF1 receptor (IGF1R) in the setting of IGF1 deficiency, which promoted sensitivity to an IGF1R-targeted antibody-drug conjugate that may serve as a novel therapeutic strategy in LPS. In summary, lineage-specific defects in adipogenesis drive dedifferentiation in LPS and may translate into selective therapeutic targeting in this disease.

cancer biology↗

Food pairing independently associated with cardiometabolic traits beyond dietary patterns across western and eastern populations

Cardiometabolic health is closely linked to diet. Both specific food choices and dietary indices are commonly used to guide cardiometabolic protection strategies. However, the balance between foods may also significantly impact cardiometabolic health. Here, we explore the balance and imbalance in long-term dietary food intake to quantify food pairing patterns (FPs), providing insights beyond conventional dietary indices and single-food intake frequencies. Using data from our GGMP (n = 6,994) and the NHANES (n = 7,350) cohorts, we observed that long-term food pairing patterns are independent of single food intake frequency and dietary indices. We identified 1,759 and 306 cardiometabolic-related long-term food pairing patterns from two cohorts (FDR < 0.05), respectively. Notably, around 80% of these pairing foods not individually associated with cardiometabolic traits, and food pairing pattern associations with cardiometabolic traits at hyper food group level were consistent across Eastern and Western populations. Besides, mediation analysis revealed that 72.7% of long-term food pairing patterns affected cardiometabolic traits through 31 microbial genera, with Clostridiumsensustricto1 playing a predominant role. Moreover, multi-step mediation analysis found that microbes mediated the impact of long-term food pairing patterns on cardiometabolic traits primarily through their metabolic pathways, such as pyruvate fermentation to propanoate and ergothioneine biosynthesis pathways. Our data suggest that balance between dietary foods is broadly associated with cardiometabolic traits by modulating gut microbial functionalities, in contrast to the lower occurrence when considering individual foods in isolation. These results offer a novel perspective for designing personalized dietary strategies beyond present dietary indices to enhance cardiometabolic health.

microbiology↗

Cells Prioritize the Regulation of Cell Mass Density

A cells global physical state is characterized by its volume and dry mass. The ratio of cell mass to volume is the cell mass density (CMD), which is also a measure of macromolecular crowding and concentrations of all proteins. Using the Fluorescence eXclusion method (FXm) and Quantitative Phase Microscopy (QPM), we investigate CMD dynamics after exposure to sudden media osmolarity change. We find that while the cell volume and mass exhibit complex behavior after osmotic shock, CMD follows a straightforward monotonic recovery in 48 hours. The recovery is cell-cycle independent and relies on a coordinated adjustment of protein synthesis and volume growth rates. Surprisingly, we find that the protein synthesis rate decreases when CMD increases. This result is explained by CMD-dependent nucleoplasm-cytoplasm transport, which serves as negative regulatory feedback on CMD. The Na+/H+ exchanger NHE plays a role in regulating CMD by affecting both protein synthesis and volume change. Taken together, we reveal that cells possess a robust control system that actively regulates CMD during environmental change.

biophysics↗

Interactions of N- and C-terminal parts of Ana1 permitting centriole duplication but not elongation

The conserved process of centriole duplication requires establishment of a Sas6-centred cartwheel initiated by Plk4s phosphorylation of Ana1/STIL. Subsequently the centriole undergoes conversion to a centrosome requiring its radial expansion and elongation, mediated by a network requiring interactions between Cep135, Ana1/Cep295, and Asterless/Cep152. Here we show that mutant alleles encoding overlapping N- and C-terminal parts of Ana1 are capable of intragenic complementation to rescue radial expansion. This permits recruitment of Asl and thereby centriole duplication and mechanosensory cilia formation to restore the coordination defects of these mutants. This genetic combination also rescues centriole duplication in the male germ line but does not rescue the elongation of the triplet microtubule-containing centrioles of primary spermatocytes and consequently these males are coordinated but sterile. Such centriole elongation is rescued by the continuous, full-length Ana1 sequence. We define a region that when deleted within otherwise intact Ana1 does not permit primary spermatocyte centrioles to elongate but still allows recruitment of Asl. Our findings point to differing demands upon the physical organization of Ana1 for the distinct processes of radial expansion and elongation of centrioles. IMPACT STATEMENTThe centriole can undergo radial development and duplication using separated parts of the conserved Ana1 protein whereas elongation of centriolar microtubule triplets requires the continuous Ana1 primary sequence.

genetics↗

Hydroxy polyethylene glycol: a solution to evade human pre-existing anti-PEG antibodies for efficient delivery

Polyethylene glycol (PEG) has been extensively utilized in food, cosmetics, and pharmaceutical fields, especially in the realm of nanomedicines, where it serves as a pivotal excipient for extending the nanoparticles circulation half-life. Contrary to its historical perception as non-immunogenic, pre-existing anti-PEG antibodies have been widely detected in human who even have never been exposed to PEGylated therapeutics, which considered to be associated with serious side effects of PEGylated nanomedicines including infusion reactions and other hypersensitive reactions. Herein, we elucidated the prevalence and distribution characteristics of pre-existing anti-PEG antibodies in 2074 human blood samples, and investigated its binding with PEG. Pre-existing anti-PEG antibodies were found to primarily recognize the PEG terminus, especially methoxy, which is the only PEG terminus contained in currently marketed PEGylated nanomedicines. While hydroxy PEG (OH-PEG) significantly evaded binding with pre-existing anti-PEG antibodies among most clinical samples. Noteworthily, substituting OH-PEG for MeO-PEG significantly mitigated complement activation of lipid nanoparticle (LNP) caused by pre-existing anti-PEG antibodies, thereby markedly enhancing stability and reducing mRNA leakage in human serum. Additionally, LNP modified with OH-PEG exhibited reduced immunogenicity, which was crucial for repeated drug administrations. The present work elucidated the crucial role of OH-PEG in evading human pre-existing anti-PEG antibodies, and discovered that the current pre-clinical studies inadequately simulated the biological effects of clinical pre-existing anti-PEG antibodies on such formulations through interspecies study, which had a profound impact on clinical translation of PEGylated nanomedicines.

pharmacology and toxicology↗