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Hu, Z.

Publications and source records attributed to Hu, Z..

At least 235 records · Page 13Linked to original sources

Structure-Uptake Relationship Studies of Oxazolidinones in Gram-negative ESKAPE Pathogens

To date, little is known about applicability and/or generality of molecular features and how they impact small molecule permeation into Gram-negative bacteria. Identifying motifs or structural trends that correlate with broad and/or species-specific permeation would enable the rational design of new antibacterials. The clinical success of linezolid for treating Gram-positive infections paired with the high conservation of bacterial ribosomes predicts that if oxazolidinones were engineered to accumulate in Gram-negative bacteria, then this pharmacological class would find broad utility in eradicating infections. Here we report an investigative study of a strategically designed library of oxazolidinones to determine the effects of molecular structure on accumulation and biological activity. E. coli, A. baumannii, and P. aeruginosa strains with varying degrees of compromise (in efflux and outer membrane) were used to identify motifs that hinder permeation across the outer-membrane and/or enhance efflux susceptibility broadly and specifically between species. The results of this study illustrate that small changes in molecular structure are enough to overcome the efflux and/or permeation issues of this scaffold. Three oxazolidinone analogs (3e, 12f, and 14) were identified from this study that exhibit activity against all three pathogens assessed, a biological profile not observed for linezolid.

microbiology↗

A phospho-switch provided by LRR receptor-like kinase, ALK1/QSK1/KIN7, prioritizes ABCG36/PEN3/PDR8 transport toward defense

Based on its proposed substrate preferences, the ABC transporter, ABCG36/PDR8/PEN3, from the model plant Arabidopsis stands at the cross-road between growth and defence. Recently, ABCG36 was shown to export a few indolic compounds, including the auxin precursor, indole-3-butyric acid (IBA), and to be implicated in the export of the major phytoalexin of Arabidopsis, camalexin, although clear-cut proof of camalexin transport activity is still lacking. Here we provide strong evidence that ABCG36 catalyses the direct, ATP-dependent export of camalexin over the plasma membrane, however, most likely in functional interplay with non-camalexin transporting ABCG isoforms. We identify the leucin-rich repeat receptor-like kinase, Auxin-induced LRR Kinase1 (ALK1/KIN7/QSK1), as a functional kinase to physically interact with and phosphorylate ABCG36. ABCG36 phosphorylation by ALK1 represses unilaterally IBA but not camalexin export leading to a prioritization of ABCG transport toward defense. As a consequence, phospho-dead mutants of ABCG36, like alk1 and abcg36 alleles, are hypersensitive toward infection with the root pathogen, F. oxysporum, caused by elevated fungal progression. Our findings indicate a novel, direct regulatory circuit between a receptor kinase and an ABC transporter determining transporter substrate specificity. It appears that growth and defense balance decisions in plants are performed on the transporter level by means of a reversible phospho-switch.

plant biology↗

Sequential functional differentiation of luminal epithelial cells regulated by maternal and embryonic signaling in the mouse endometrium

Embryo implantation requires temporospatial maternal-embryo dialog to regulate the interactions between an activated blastocyst and a receptive endometrium; however, the details of the related cell-specific coordination is largely unknown because of the cellular complexity and dynamic developmental processes of both the embryo and endometrium during peri-implantation. By comparing single-cell RNA (scRNA) data obtained from entire uteri of pregnant and pseudo-pregnant mice with embryos that were in the oviduct (dpc2.5 days post-coitum [dpc]) or had entered the uterus (after 3.5 dpc), we found a maternal estrogen and progesterone signaling-dependent functional differentiation process in which progesterone induced estrogen-responsive luminal epithelial cells to differentiate into two new types of epithelial cells: adhesion epithelial cells (AECs) and supporting epithelial cells (SECs) on 2.5 dpc. In addition to maternal signaling data, the uterine scRNA and corresponding embryo bulk sequencing data were obtained, and analyses revealed that embryonic Pdgfa and Efna3/4 signaling activated AECs and SECs, enhancing the attachment of embryos to the endometrium after implantation. Specifically, embryonic signaling induced additional transformation of AECs by preventing adjacent AECs, but not AECs away from the embryo in the implantation chamber, from undergoing apoptosis. Furthermore, we demonstrated that epithelial cell differentiation and related regulatory signaling were largely conserved in humans and mice. In the human endometrium, developmental defects of SOX9-positive epithelial cells similar to luminal epithelial cells were related to thin endometrium. Our work provides comprehensive and systematic information on endometrial luminal epithelial cell development directed by maternal and embryonic signaling, which is important for endometrial receptivity and embryo implantation.

cell biology↗

CASK and FARP coordinately control pre- and post-synaptic function

Changes in neurotransmitter receptor abundance at post-synaptic elements play a pivotal role in regulating synaptic strength. For this reason, there is significant interest in identifying and characterizing the scaffolds required for receptor localization at different synapses. Here we analyze the role of two C. elegans post-synaptic scaffolding proteins (LIN-2/CASK and FRM-3/FARP) at cholinergic neuromuscular junctions. Constitutive knockouts or muscle specific inactivation of lin-2 and frm-3 dramatically reduced spontaneous and evoked post-synaptic currents. These synaptic defects resulted from the decreased abundance of two classes of post-synaptic ionotropic acetylcholine receptors (ACR-16/CHRNA7 and levamisole-activated AChRs). LIN-2s AChR scaffolding function is mediated by its SH3 and PDZ domains, which interact with AChRs and FRM-3/FARP, respectively. Thus, our findings show that post-synaptic LIN-2/FRM-3 complexes promote cholinergic synaptic transmission by recruiting AChRs to post-synaptic elements.

neuroscience↗

Making Biomedical Research Software FAIR: Actionable Step-by-step Guidelines with a User-support Tool

Findable, Accessible, Interoperable, and Reusable (FAIR) guiding principles tailored for research software have been proposed by the FAIR for Research Software (FAIR4RS) Working Group. They provide a foundation for optimizing the reuse of research software. The FAIR4RS principles are, however, aspirational and do not provide practical instructions to the researchers. To fill this gap, we propose in this work the first actionable step-by-step guidelines for biomedical researchers to make their research software compliant with the FAIR4RS principles. We designate them as the FAIR Biomedical Research Software (FAIR-BioRS) guidelines. Our process for developing these guidelines, presented here, is based on an in-depth study of the FAIR4RS principles and a thorough review of current practices in the field. To support researchers, we have also developed a workflow that streamlines the process of implementing these guidelines. This workflow is incorporated in FAIRshare, a free and open-source software application aimed at simplifying the curation and sharing of FAIR biomedical data and software through user-friendly interfaces and automation. Details about this tool are also presented.

scientific communication and education↗

Broadly neutralizing antibodies target the coronavirus fusion peptide

The potential for future coronavirus outbreaks highlights the need to develop strategies and tools to broadly target this group of pathogens. Here, using an epitope-agnostic approach, we identified six monoclonal antibodies that bound to spike proteins from all seven human-infecting coronaviruses. Epitope mapping revealed that all six antibodies target the conserved fusion peptide region adjacent to the S2 cleavage site. Two antibodies, COV44-62 and COV44-79, broadly neutralize a range of alpha and beta coronaviruses, including SARS-CoV-2 Omicron subvariants BA.1 and BA.2, albeit with lower potency than RBD-specific antibodies. In crystal structures of Fabs COV44-62 and COV44-79 with the SARS-CoV-2 fusion peptide, the fusion peptide epitope adopts a helical structure and includes the arginine at the S2 cleavage site. Importantly, COV44-79 limited disease caused by SARS-CoV-2 in a Syrian hamster model. These findings identify the fusion peptide as the target of the broadest neutralizing antibodies in an epitope-agnostic screen, highlighting this site as a candidate for next-generation coronavirus vaccine development. One-Sentence SummaryRare monoclonal antibodies from COVID-19 convalescent individuals broadly neutralize coronaviruses by targeting the fusion peptide.

immunology↗

Additive and Dominant Loci Jointly Pyramiding the Grain Quality of Hybrid Rice

Hybrid rice has an advantage in its heterosis, resulting in high yield and resistance to biotic and abiotic stress. However, genetic improvement of grain quality is more challenging in hybrid rice than in inbred rice due to additional complexity, such as the dominant effect. It is critical to identify a path to efficiently develop inbreds and identify their superior crosses for hybrid production. Here, we developed a pipeline for joint analysis of phenotypes, effects, and generations (JPEG) and analysed 113 inbred varieties as male parents, five tester varieties as female parents, and their 565 (113x5) hybrid testcrosses for 12 grain quality traits, including grain length and width, chalkiness, and amylose content. A total of 1,619,588 single nucleotide polymorphisms were obtained for the parent varieties and inferred for the hybrids using whole-genome sequencing with an average sequencing depth of 11x. Genome-wide association studies with JPEG identified 128 loci associated with at least one of the 12 traits. There were 44 and 97 loci with additive and dominant effects, respectively, including 13 overlaps. Among the 128 associated loci, 42 loci are located in or near (<200 kb) 17 known genes. Pyramiding genetic loci with additive and/or dominant effects in genomic selection dramatically improves the accuracy of predicting hybrid performances. More than 45% of genetic variation was explained by the identified markers for all traits except one (30%). These results demonstrate that pyramiding genetically identified additive and dominant loci can afford substantial power for predicting hybrid performances, presenting opportunities to identify superior crosses from existing phenotypes and genotypes of inbreds and hybrids.

plant biology↗

Antibody Resistance of SARS-CoV-2 Omicron BA.1, BA.1.1, BA.2 and BA.3 Sub-lineages

The SARS-CoV-2 Omicron variant has been partitioned into four sub-lineages designated BA.1, BA.1.1, BA.2 and BA.3, with BA.2 becoming dominant worldwide recently by outcompeting BA.1 and BA.1.1. We and others have reported the striking antibody evasion of BA.1 and BA.2, but side-by-side comparison of susceptibility of all the major Omicron sub-lineages to vaccine-elicited or monoclonal antibody (mAb)-mediated neutralization are urgently needed. Using VSV-based pseudovirus, we found that sera from individuals vaccinated by two doses of inactivated whole-virion vaccines (BBIBP-CorV) showed very weak to no neutralization activity, while a homologous inactivated vaccine booster or a heterologous booster with protein subunit vaccine (ZF2001) markedly improved the neutralization titers against all Omicron variants. The comparison between sub-lineages indicated that BA.1.1, BA.2 and BA.3 had comparable or even greater antibody resistance than BA.1. We further evaluated the neutralization profile of a panel of 20 mAbs, including 10 already authorized or approved, against these Omicron sub-lineages as well as viruses with different Omicron spike single or combined mutations. Most mAbs lost their neutralizing activity completely or substantially, while some demonstrated distinct neutralization patterns among Omicron sub-lineages, reflecting their antigenic difference. Taken together, our results suggest all four Omicron sub-lineages threaten the efficacies of current vaccines and antibody therapeutics, highlighting the importance of vaccine boosters to combat the emerging SARS-CoV-2 variants.

microbiology↗

LTD-inducing low frequency stimulation enhances p-Tau181 and p-Tau217 in an age-dependent manner in live rats

The progressive cognitive decline in Alzheimers disease (AD) patients correlates with the extent of tau pathology, in particular tau hyperphosphorylation, which is strongly age-associated. Although elevation of phosphorylated tau (p-Tau) on residues Thr181 (p-Tau181), Thr217 (p-Tau217), and Thr231 (p-Tau231) in cerebrospinal fluid or blood are recently proposed to be particularly sensitive markers of early AD, the generation of p-Tau during brain activity is poorly understood. A major form of synaptic plasticity, long-term depression (LTD), has recently been linked to the enhancement of tau phosphorylation. Here we show that low frequency stimulation (LFS), used to induce LTD, enhances p-Tau181 and p-Tau217 in an age-dependent manner in the hippocampus of live rats. In contrast, phosphorylation at residues Thr231, Ser202/Thr205, and Ser396 is less sensitive to LFS. Pharmacological antagonism of either NMDA or metabotropic glutamate 5 (mGluR5) receptors inhibits the elevation of both p-Tau181 and p-Tau217. Targeting ageing with a small molecule cognitive enhancer ISRIB (trans-isomer) prevents the enhancement of p-Tau by LFS in aged rats. Together, our data provide an in vivo means to uncover brain plasticity-related cellular and molecular processes of tau phosphorylation in health and ageing conditions.

neuroscience↗

Alveolar regeneration following viral infection is independent of tuft cells

Severe injuries following viral infection cause lung epithelial destruction with the presence of ectopic basal progenitor cells (EBCs), although the exact function of EBCs remains controversial. We and others previously showed the presence of ectopic tuft cells in the disrupted alveolar region following severe influenza infection. Here, we further revealed that the ectopic tuft cells are derived from EBCs. This process is amplified by Wnt signaling inhibition but suppressed by Notch inhibition. Further analysis revealed that p63-CreER labeled population de novo arising during regeneration includes alveolar epithelial cells when Tamoxifen was administrated after viral infection. The generation of the p63-CreER labeled alveolar cells is independent of tuft cells, demonstrating segregated differentiation paths of EBCs in lung repair. EBCs and ectopic tuft cells can also be found in the lung parenchyma post SARS-CoV-2 infection, suggesting a similar response to severe injuries in humans.

cell biology↗

TBK1 phosphorylation activates LIR-dependent degradation of the inflammation repressor TNIP1

Limitation of excessive inflammation due to selective degradation of pro-inflammatory proteins is one of the cytoprotective functions attributed to autophagy. In the current study, we highlight that selective autophagy also plays a vital role in promoting the establishment of a robust inflammatory response. Under inflammatory conditions, here TLR3-activation by poly(I:C) treatment, the inflammation repressor TNIP1 (TNFAIP3 interacting protein 1) is phosphorylated by TBK1 (Tank-binding kinase 1) activating a LIR motif that leads to the selective autophagy-dependent degradation of TNIP1, supporting expression of pro-inflammatory genes and proteins. Thus, similarly as in cancer, autophagy may play a dual role in controlling inflammation depending on the exact state and timing of the inflammatory response. SummaryAutophagy is well known for its anti-inflammatory effects. Here, we highlight that selective, autophagy-dependent degradation of the inflammation repressor TNIP1 supports pro-inflammatory gene and protein expression. Similarly as in cancer, autophagy appears to play a dual role in controlling inflammation.

cell biology↗

Rapid GPR183-mediated recruitment of eosinophils to the lung after Mycobacterium tuberculosis infection

Influx of eosinophils into the lungs is typically associated with type-II responses during allergy, fungal and parasitic infections. However, we previously reported that eosinophils accumulate in lung lesions during type-I inflammatory responses to Mycobacterium tuberculosis (Mtb) in humans, macaques, and mice where they contribute to host resistance. Here we show eosinophils migrate into the lungs of macaques and mice as early as one week after Mtb-exposure. In mice this influx was CCR3 independent and instead required cell-intrinsic expression of the oxysterol-receptor GPR183, which is highly expressed on human and macaque eosinophils. Murine eosinophils interacted directly with bacilli-laden alveolar macrophages, which upregulated the oxysterol-synthesizing enzyme Ch25h, and eosinophil recruitment was impaired in Ch25h deficient mice. Our findings show that eosinophils are among the first cells from circulation to sense and respond to Mtb infection of alveolar macrophages and reveal a novel role for GPR183 in the migration of eosinophils into lung tissue. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/480919v1_ufig1.gif" ALT="Figure 1"> View larger version (105K): org.highwire.dtl.DTLVardef@e8cd29org.highwire.dtl.DTLVardef@1f5769borg.highwire.dtl.DTLVardef@3dce9borg.highwire.dtl.DTLVardef@1c75587_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSIn mice and macaques eosinophils accumulate early in Mtb-infected lungs preceding neutrophils Eosinophils interact with Mtb-infected cells in the alveoli in mice Early pulmonary eosinophil migration occurs independently of CCR3 in mice Early lung migration in mice requires Ch25h and eosinophil-intrinsic GPR183 expression

immunology↗

In silico drug design of benzothiadiazine derivatives interactingwith bilayer cell membranes

The use of drugs derived from benzothiadiazine, a bicyclic heterocyclic benzene derivative, has become a widespread treatment for diseases such as hypertension, low blood sugar or the human immunodeficiency virus, among others. In this work we have investigated the interactions of benzothiadiazine and several selected derivatives designed in silico, with the basic components of cell membranes and solvents such as phospholipids, cholesterol and water. The analysis of the mutual microscopic interactions is of central importance to elucidate the local structure of benzothiadiazine as well as the mechanisms responsible for the distribution and access of benzothiadiazine to the interior of the cell. We have performed molecular dynamics simulations of benzothiadiazine and its derivatives embedded in a model zwitterionic bilayer membrane made by phospholipids dioleoylphosphatidylcholine, 1,2-dioleoyl-sn-glycero-3-phosphoserine and cholesterol inside aqueous potassium chloride solution in order to systematically examine microscopic interactions of benzothiadiazine derivatives with the cell membrane at liquid-crystalline phase conditions. From data obtained through radial distribution functions, time dependent hydrogen-bond lengths and potentials of mean force based on reversible work calculations, we have observed that benzothiadiazine derivatives have a strong affinity to stay at the cell membrane interface although their solvation characterisitics can vary significantly: they can be fully solvated by water in short periods of time or continuously attached to specific lipid sites during intervals of 10-70 ns. Furthermore, benzothiadiazines are able to bind lipids and cholesterol chains by means of single and double hydrogen-bonds of different characteristic lengths between 1.6 and 2.1 [A].

biophysics↗

CaSee: A lightning transfer-learning model directly used to discriminate cancer/normal cells from scRNA-seq

Single-cell RNA sequencing (scRNA-seq) is one of the most efficient technologies for human tumor research. However, data analysis is still faced with some technical challenges, especially the difficulty in efficiently and accurately discriminate cancer/normal cells in the scRNA-seq expression matrix. In this study, we developed a cancer/normal cell discrimination pipeline called pan-cancer seeker (CaSee) devoted to scRNA-seq expression matrix, which is based on the traditional high-quality pan-cancer bulk sequencing data using transfer learning. It is compatible with mainstream sequencings technology platforms, 10x Genomics Chromium, Smart-seq2, and Microwell-seq. Here, CaSee pipeline exhibited excellent performance in the multicenter data evaluation of 11 retrospective cohorts and one independent dataset, with an average discrimination accuracy of 96.69%. In general, the development of a deep-learning based, pan-cancer cell discrimination model, CaSee, to distinguish cancer cells from normal cells will be compelling to researchers working in the genomics, cancer, and single-cell fields.

bioinformatics↗

Knockout of OsSWEET15 impaired rice embryo formation and seed-setting

we show that the knockout of a sugar transporter gene OsSWEET15 led to a significant drop in rice fertility because near half of the knockout mutant spikelets bore blighted or empty grains. The rest spikelets bore fertile grains with slightly reduced weight. Notably, the ovaries in the blighted grains of the ossweet15 mutants expanded after flowering but terminated development before the endosperm cellularization stage and aborted subsequently. GUS and GFP representing OsSWEET15 expression showed that the protein was strongly expressed in the embryo surrounding region (ESR) which was supposed to supply nutrients for the embryo development. These results joined with the proteins sucrose transport capacity and plasma membrane localization suggest that OsSWEET15 plays a prominent role during the caryopsis formation stage probably by releasing sucrose from the ESR to support the embryo development. By contrast, the empty grains were probably caused by the reduced pollen viability of the ossweet15 mutants. Investigation of the makeup of ossweet11 mutant grains revealed similar phenotypes that were observed in the ossweet15 mutants. These results indicate that both OsSWETT15 and OsSWEET11 play important and similar roles during rice pollen development, caryopsis formation, and seed-setting in addition to their function in seed-filling that was demonstrated previously.

plant biology↗

Decoding the temporal dynamics of affective scene processing

Natural images containing affective scenes are used extensively to investigate the neural mechanisms of visual emotion processing. Functional fMRI studies have shown that these images activate a large-scale distributed brain network that encompasses areas in visual, temporal, and frontal cortices. The underlying spatial and temporal dynamics among these network structures, however, remain to be characterized. We recorded simultaneous EEG-fMRI data while participants passively viewed affective images from the International Affective Picture System (IAPS). Applying multivariate pattern analysis to decode EEG data, and representational similarity analysis to fuse EEG data with simultaneously recorded fMRI data, we found that: (1) ~100 ms after picture onset, perceptual processing of complex visual scenes began in early visual cortex, proceeding to ventral visual cortex at ~160 ms, (2) between ~200 and ~300 ms (pleasant pictures: ~200 ms; unpleasant pictures: ~260 ms), affect-specific neural representations began to form, supported mainly by areas in occipital and temporal cortices, and (3) affect-specific neural representations, lasting up to ~2 s, were stable and exhibited temporally generalizable activity patterns. These results suggest that affective scene representations in the brain are formed in a valence-dependent manner and are sustained by recurrent neural interactions among distributed brain areas.

neuroscience↗

The Intrinsically Disordered Region of Coronins Fine-tunes Oligomerization and Actin Polymerization

Coronins are highly conserved actin-binding proteins (ABPs) in the eukaryotic kingdom for polymerizing actin cytoskeleton. The biochemical activity of coronins is primarily mediated by the structural N-terminal {beta}-propeller and the C-terminal helical coiled-coil (CC) domains, but less is known about the function of a middle nonconserved region, the "unique region (UR)". The coronin UR is an intrinsically disordered region (IDR). Herein, we demonstrate that the low complexity of the UR is a conserved signature of the coronin protein family, and the UR/IDR exhibits a striking evolutionary correlated pattern associated with sequence length. By analyzing the role of the IDR in coronins via coarse-grained simulations, we reveal that evolutionary selection of IDR length is coupled with the oligomerization of IDR-containing proteins (IDPs) to provide optimal functional output. By integrating biochemical and cell biology experiments and protein engineering, we found that the IDR regulates Crn1 biochemical activity, both in vivo and in vitro, by fine-tuning CC domain oligomerization and maintaining Crn1 in a tetrameric state. The IDR-guided optimization of Crn1 oligomerization is critical for Arp2/3-mediated actin polymerization.

cell biology↗

conST: an interpretable multi-modal contrastive learning framework for spatial transcriptomics

MotivationSpatially resolved transcriptomics (SRT) shows its impressive power in yielding biological insights into neuroscience, disease study, and even plant biology. However, current methods do not sufficiently explore the expressiveness of the multi-modal SRT data, leaving a large room for improvement of performance. Moreover, the current deep learning based methods lack interpretability due to the "black box" nature, impeding its further applications in the areas that require explanation. ResultsWe propose conST, a powerful and flexible SRT data analysis framework utilizing contrastive learning techniques. conST can learn low-dimensional embeddings by effectively integrating multi-modal SRT data, i.e. gene expression, spatial information, and morphology (if applicable). The learned embeddings can be then used for various downstream tasks, including clustering, trajectory and pseudotime inference, cell-to-cell interaction, etc. Extensive experiments in various datasets have been conducted to demonstrate the effectiveness and robustness of the proposed conST, achieving up to 10% improvement in clustering ARI in the commonly used benchmark dataset. We also show that the learned embedding can be used in complicated scenarios, such as predicting cancer progression by analyzing the tumour microenvironment and cell-to-cell interaction (CCI) of breast cancer. Our framework is interpretable in that it is able to find the correlated spots that support the clustering, which matches the CCI interaction pairs as well, providing more confidence to clinicians when making clinical decisions.

bioinformatics↗