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Yang, Y.

Publications and source records attributed to Yang, Y..

At least 1,171 records · Page 65Linked to original sources

EMPress enables tree-guided, interactive, and exploratory analyses of multi-omic datasets

Standard workflows for analyzing microbiomes often include the creation and curation of phylogenetic trees. Here we present EMPress, an interactive tool for visualizing trees in the context of microbiome, metabolome, etc. community data scalable beyond modern large datasets like the Earth Microbiome Project. EMPress provides novel functionality--including ordination integration and animations--alongside many standard tree visualization features, and thus simplifies exploratory analyses of many forms of omic data.

bioinformatics↗

Airway bacterial and fungal microbiome in chronic obstructive pulmonary disease

BackgroundLittle is known about airway mycobiome, and its relationship with bacterial microbiome in chronic obstructive pulmonary disease (COPD). MethodsHere we report the first simultaneous characterization of sputum bacterial and fungal microbiome in 84 stable COPD and 29 healthy subjects, using 16S ribosomal DNA and fungal internal transcribed spacer DNA sequencing. ResultsAscomycota predominated over Basidiomycota in fungal microbiome both in COPD patients and healthy controls. Meyerozyma, Candida, Aspergillus and Schizophyllum were most abundant at the genus level. There was a significant inverse correlation between bacterial and fungal microbial diversity, both of which altered in opposite directions in COPD patients versus controls, and in frequent versus non-frequent exacerbators. An enhanced bacterial-fungal ecological interaction was observed in COPD patients, which was characterized by higher proportion of co-occurrence intrakingdom interactions and co-exclusive interkingdom interactions. In COPD, four mutually co-occurring fungal operational taxonomic units (OTUs) in Candida palmioleophila, Aspergillus and Sordariomycetes exhibited co-exclusive relationships with other fungal OTUs, which was specifically present in frequent exacerbators but not in non-frequent exacerbators. Conversely, the mutual co-occurrence interactions between bacterial OTUs in Rothia mucilaginosa, Streptococcus, Veillonella and Prevotella, showed up in non-frequent exacerbators but not in frequent exacerbators. The perturbed bacterial-fungal interactions in COPD were associated with increased airway inflammatory mediators such as IL-6 and IL-8. InterpretationThe disruption of airway bacterial-fungal community balance, characterized by the loss of commensal bacterial taxa and enriched pathogenic fungal taxa, is implicated in COPD. The airway mycobiome is an important cofactor mediating COPD pathogenic infection and host inflammation. Clinical Trial Registrationwww.clinicaltrials.gov (NCT 03240315).

microbiology↗

Integrative identification by Hi-C revealed distinct advanced structural variations in Lung Adenocarcinoma tissue

Advanced three-dimensional structure variations of chromatin in large genome fragments, such as conversion of A/B compartment, topologically associated domains (TADs) and chromatin loops are related closely to occurrence of malignant tumors. However, the structural characteristics of lung cancer still remain uncovered. In this study, we used high-throughput chromosome (HiC) confirmation capture to detect 2 non-smoking female lung adenocarcinoma (LUAD) tumor and paired normal tissues. The results indicated that significant chromatin variations were detected in tumor tissues compared with normal tissues. At compartment scale, the main conversion type of compartment is A[->]B in tumor tissues, which concentrated mainly on chromosome 3 (33.6%). Total of 216 tumor-specific TADs were identified in tumor tissues, which distributed mainly in chr1 (19), chr2 (15) and chr3(17). Finally we observed 41 distinct enhancer-promoter loops in tumor tissue, which associated closely to tumor-related pathways including MAPK, PI3K-AKT, Ras, Wnt and Ras1. The most important observation in this study was that we identified 5 important genes (SYT16, NCEH1, NXPE3, MB21D2, and DZIP1L), which were detected in both A[->]B compartment, TADs and chromatin loops. Four of these genes (NCEH1, NXPE3, MB21D2, and DZIP1L) located on q arm of chromosome 3, which also revealed the importance of chr3 in occurrence of structural variations in LUAD.

cancer biology↗

Efficient Multiplex Genome Editing Tools Identified by Protoplast Technology in Phalaenopsis

Phalaenopsis orchids are popular ornamental plants worldwide. The application of the efficient multiplex genome editing tools in Phalaenopsis, will greatly accelerate the development of orchid gene function and breeding research. In this study, we establish a fast and convenient Phalaenopsis protoplast platform for the identification of functional genome editing tools. Two multiplex genome editing tools, PTG-Cas9 (PTG, polycistronic tRNA gRNA) system and PTGm-Cas9 (PTG-Cas9 system with modified sgRNA structure) system are designed to edit PDS gene of commercial Phalaenopsis ST166 at four target sites. We find that both PTG-Cas9 and PTGm-Cas9 system are functional in Phalaenopsis, and the PTGm-Cas9 system with modified sgRNA has a higher editing efficiency than PTG-Cas9 system. Further, we design another multiplex genome editing tool, termed as DPII-Cpf1 system (dual Pol II promoter to drive the expression of Cpf1 endonuclease and crRNA), to edit PDS gene of Phalaenopsis at four target sites likewise. All the four targets are efficiently edited by DPII-Cpf1 system, and the total mutation rate is about 3 times higher than that of PTGm-Cas9 system. Taken together, using the Phalaenopsis protoplast platform, we successfully establish two efficient multiplex genome editing tools for Phalaenopsis research, PTGm-Cas9 and DPII-Cpf1. The multiplex genome editing tools established in this study have great application potentials in efficiently constructing large-scale knockout mutant libraries of orchid and speeding up orchid precise breeding.

plant biology↗

Higher-order sensorimotor circuit of the brain' global network supports human consciousness

The neural correlates of consciousness, defined as the minimum neuronal mechanisms sufficient for any conscious percept, are usually subject to different interpretations depending on whether one uses measures of local or global brain activities. We argue that the local regions may support consciousness by serving as hubs within the brains global network. We adopt a unique functional magnetic resonance imaging resting state dataset that encompasses various conscious states, including non-rapid eye movement (NREM)-sleep, rapid eye movement (REM)-sleep, anesthesia, and brain injury patients. Using a graph-theoretical measure for detecting local hubs within the brains global network, we identify various higher-order sensory and motor regions as hubs with significantly reduced degree centrality during unconsciousness. Additionally, these regions form a sensorimotor circuit which correlates with levels of consciousness. Our findings suggest that integration of higher-order sensorimotor function may be a key mechanism of consciousness. This opens novel perspectives for therapeutic modulation of unconsciousness.

neuroscience↗

Outer membrane lipoprotein DolP interacts with the BAM complex and promotes fitness during envelope stress response

In Gram-negative bacteria, coordinated remodelling of the outer membrane (OM) and the peptidoglycan is crucial for envelope integrity. Envelope stress caused by unfolded OM proteins (OMPs) activates sigmaE ({sigma}E) in Enterobacteria. {sigma}E upregulates OMP biogenesis factors, including the {beta}-barrel assembly machinery (BAM) that catalyzes OMP-folding. Elevated {sigma}E activity, however, can be detrimental for OM integrity. Here we report that DolP (YraP), a {sigma}E-upregulated OM lipoprotein important for envelope integrity, is a novel interactor of BAM and we demonstrate that OM-assembled BamA is a critical determinant of the BAM-DolP complex. Mid-cell recruitment of DolP had been previously associated to activation of septal peptidoglycan remodelling during cell division, but its role during envelope stress was unknown. We now show that DolP promotes cell fitness upon stress-induced activation of {sigma}E and opposes a detrimental effect caused by the overaccumulation of BAM in the OM. During envelope stress, DolP loses its association with the mid-cell, thus suggesting a possible link between envelope stress caused by impaired OMP biogenesis and the regulation of a late step of cell division.

microbiology↗

Transcriptome analysis of potato leaves in response to infection with the necrotrophic pathogen Alternaria solani

The potato early blight was caused by Alternaria solani (Aso). At present, potato early blight resistant varieties are lacking. The experiment of Aso inoculation on a.k.a. Favorita showed that the content of chlorophyll decreased continuously within 2 days after inoculation. In addition, the contents of JA-Ile, SA, ABA and IAA were determined by LC-MS.The results of two defense-related hormones showed that jasmonic acid content decreased significantly, while jasmonic acid content did not change significantly. In order to understand the difference in gene expression of potatoes infected by Aso, the 24 hpi, 36 hpi and 48 hpi transcriptome were determined. The results showed that the gene annotation and cluster analysis of DEGs revealed a variety of defense responses to Aso infection, especially the plant hormone signal transduction pathway. The differential expression of 10 DEGs was confirmed by qPCR analysis. Finally, through weighted gene co-expression network analysis (WGCNA), "samonl" was determined as a key hormone-related network in the process of Aso infection in potatoes. This study provides an important clue for understanding the interaction between potato and Aso and for disease resistance breeding.

plant biology↗

D1, not D2, dopamine receptor activation dramatically improves MPTP-induced parkinsonism unresponsive to levodopa

AO_SCPLOWBSTRACTC_SCPLOWLevodopa is the Parkinsons disease standard-of-care, but continued loss of dopamine neurons with disease progression decreases its bioconversion to dopamine, leading to increased side effects and decreased efficacy. In theory, dopamine agonists could equal levodopa, but no approved oral "dopamine agonist" matches the efficacy of levodopa. Although there are consistent data in both primate models and in Parkinsons disease showing that selective high intrinsic activity D1 agonists can equal levodopa, there are no data on whether such compounds would be effective in severe disease when levodopa efficacy is lower or even absent. We compared two approved antiparkinson drugs (levodopa and the D2/3 agonist bromocriptine) with the experimental selective D1 full agonist dihydrexidine in two severely parkinsonian MPTP-treated non-human primates. Bromocriptine caused no discernable improvement in parkinsonian signs, whereas levodopa caused a small transient improvement in one of the two subjects. Conversely, the full D1 agonist dihydrexidine caused a dramatic improvement in both subjects, decreasing parkinsonian signs by ca. 75%. No attenuation of dihydrexidine effects was observed when the two subjects were pretreated with the D2 antagonist remoxipride. These data provide evidence that selective D1 agonists may provide profound antiparkinson symptomatic relief even when the degree of nigrostriatal degeneration is so severe that current drugs are ineffective. Until effective disease-modifying therapies are discovered, high intrinsic activity D1 agonists may offer a major therapeutic advance in improving the quality of life, and potentially the longevity, of late stage Parkinsons patients.

neuroscience↗

Tripartite holobiont system in a vent snail broadens the concept of chemosymbiosis

Many animals inhabiting deep-sea vents are energetically dependent on chemosynthetic endosymbionts, but how such symbiont community interacts with host, and whether other nutritional sources are available to such animals remain unclear. To reveal the genomic basis of symbiosis in the vent snail Alviniconcha marisindica, we sequenced high-quality genomes of the host and gill campylobacterial endosymbionts, as well as metagenome of the gut microbiome. The gill endosymbiont has a streamlined genome for efficient chemoautotrophy, but also shows metabolic heterogeneity among populations. Inter- and intra-host variabilities among endosymbiont populations indicate the host poses low selection on gill endosymbionts. Virulence factors and genomic plasticity of the endosymbiont provide advantages for cooperating with host immunity to maintain mutualism and thriving in changing environments. In addition to endosymbiosis, the gut and its microbiome expand the holobionts utilisation of energy sources. Host-microbiota mutualism contributes to a highly flexible holobiont that can excel in various extreme environments.

ecology↗

HetF protein is a new divisome component in a filamentous and developmental cyanobacterium

Bacterial cell division, with a few exceptions, is driven by FtsZ through a treadmilling mechanism to remodel and constrict the rigid peptidoglycan (PG) layer. Yet, different organisms may differ in the composition of the cell-division complex (divisome). In the filamentous cyanobacterium Anabaena PCC 7120, hetF is required for the initiation of the differentiation of heterocysts, cells specialized in N2-fixing cells under combined nitrogen deprivation. In this study, we demonstrate that hetF is expressed in vegetative cells and necessary for cell division in a conditional manner. Under non-permissive conditions, cells of a {Delta}hetF mutant stop dividing, consistent with increased level of HetF under similar conditions in the wild type. Furthermore, HetF is a membrane protein located at midcell and cell-cell junctions. In the absence of HetF, FtsZ rings are still present in the elongated cells; however, PG remodelling is abolished. This phenotype is similar to that observed with the inhibition of septal PG synthase FtsI. We further reveal that HetF is recruited to or stabilized at the divisome by interacting with FtsI and this interaction is necessary for HetF function in cell division. Our results indicate that HetF is a member of the divisome, and reveal distinct features of the cell-division machinery in cyanobacteria that are of high ecological and environmental importance. Significance StatementCyanobacteria shaped the Earths evolutionary history, and are still playing important roles for elementary cycles in different environments. They are consisted of highly diverse species with different cell shape, size and morphology. Although these properties are strongly affected by the process of cytokinesis, the mechanism remains largely unexplored. Using different approaches, we demonstrate that HetF is a new component of the cell division machinery in the filamentous cyanobacterium Anabaena PCC 7120. The common and diverged characteristics of cell division in prokaryotes reflect the evolutionary history of different bacteria, as an adaptive measure to proliferate under certain environmental conditions. As a protein for cell differentiation, the recruitment of HetF to the septum illustrates such an adaptive mechanism for cyanobacteria.

microbiology↗

Visualizing and isolating iron-reducing microorganisms at single cell level

Iron-reducing microorganisms (FeRM) play key roles in many natural and engineering processes. Visualizing and isolating FeRM from multispecies samples are essential to understand the in-situ location and geochemical role of FeRM. Here, we visualized FeRM by a "turn-on" Fe2+-specific fluorescent chemodosimeter (FSFC) with high sensitivity, selectivity and stability. This FSFC could selectively identify and locate active FeRM from either pure culture, co-culture of different bacteria or sediment-containing samples. Fluorescent intensity of the FSFC could be used as an indicator of Fe2+ concentration in bacterial cultures. By integrating FSFC with a single cell sorter, we obtained three FSFC-labeled cells from an enriched consortia and all of them were subsequently evidenced to be capable of iron-reduction and two unlabeled cells were evidenced to have no iron-reducing capability, further confirming the feasibility of the FSFC. ImportanceVisualization and isolation of FeRM from samples containing multispecies are commonly needed by researchers from different disciplines, such as environmental microbiology, environmental sciences and geochemistry. However, no available method has been reported. In this study, we provid a solution to visualize FeRM and evaluate their activity even at single cell level. Integrating with single cell sorter, FeRM can also be isolated from samples containing multispecies. This method can be used as a powerful tool to uncover the in-situ or ex-situ role of FeRM and their interactions with ambient microbes or chemicals.

microbiology↗

The Combination of Morphology and Surface Chemistry Defines the Biological Identity of Nanocarriers in Human Blood

Following intravenous administration, an adsorbed corona of blood proteins immediately forms on the surfaces of nanocarriers to confer a distinct biological identity that dictates interactions with the immune system. While the nanocarrier surface chemistry has long been the focus of protein corona formation, the influence of the nanocarrier structure has remained unclear despite well-documented influences on biodistribution, clearance and inflammation. Here, we present design rules for the combined engineering of both nanocarrier structure and surface chemistry derived from a comprehensive proteomic analysis of protein corona formation in human blood. A library of nine soft PEGylated nanocarriers that differ in their combination of morphology (spheres, vesicles, and cylinders) and surface chemistry (methoxy, hydroxyl, and phosphate) were synthesized to represent properties of commonly employed drug delivery vehicles. Using label-free proteomics and high-throughput techniques, we examined the relationship between physicochemical properties and the resulting nanocarrier biological identity, including dynamic changes in protein corona composition, differential immunostimulation and uptake by relevant immune cell populations. In human blood, non-polar spherical micelles developed a similar biological identity to polar vesicles, whereas the identities of polar spheres and cylinders resembled that of non-polar vesicles. The formed protein coronas were compositionally dynamic and morphology-dependent, and these time-dependent fingerprints altered nanocarrier complement activation as well as their uptake by human monocytes, macrophages, and dendritic cells. This comprehensive analysis provides mechanistic insights into rational design choices that impact nanocarrier fate in human blood. One Sentence SummaryWe demonstrate that not only the surface chemistry, but the combined chemical and structural properties of soft drug delivery vehicles impact the composition of blood proteins that adsorb to their surfaces, and these differences specify their interactions with and modulation of human immune cells.

bioengineering↗

Ciliary signaling-patterned smooth muscle drives tubular elongation

During development, many tubular organs undergo extensive longitudinal growth to reach their defined length, essential for their function, but how they lengthen is poorly understood. Here, we found that primary cilia are critical for the elongation of the small intestine and esophagus during murine embryonic development. More specifically, HH ligands produced by the epithelium signaled via cilia in the surrounding mesenchyme to pattern the smooth muscle. Like attenuated ciliary HH signaling, partial ablation of the smooth muscle reduced elongation, revealing an essential role for smooth muscle in longitudinal growth. Disruption of cilia, HH signaling or the smooth muscle reduced residual stress within the gut wall, indicating that smooth muscle contributes to the mechanical properties of the developing gut. Reducing residual stress decreased nuclear YAP, an effector of the mechanotransductive Hippo pathway. Removing YAP in the mesenchyme did not affect smooth muscle formation, but attenuated proliferation and elongation, demonstrating that YAP interprets smooth muscle-generated force to promote proliferation. Together, our results reveal that ciliary signaling directs the formation of the smooth muscle layer which, in turn, generates mechanical forces that activate YAP-mediated proliferation. As this interplay of biochemical and mechanical signals drives elongation of both the esophagus and small intestine, we propose that this mechanism may underlie tubular organ elongation generally. HighlightsO_LIPrimary cilia are essential for the elongation of the small intestine and esophagus during embryonic development C_LIO_LICiliary signaling patterns the smooth muscle in the developing intestine and esophagus C_LIO_LIThe smooth muscle contributes to tissue mechanics C_LIO_LISmooth muscle-generated strain activates YAP to drive longitudinal growth of the tubular organs C_LI

developmental biology↗

Stochastic pausing at latent HIV-1 promoters generates transcriptional bursting

Promoter-proximal polymerase pausing is a key process regulating gene expression. In latent HIV-1 cells, it prevents viral transcription and is essential for latency maintenance, while in acutely infected cells the viral factor Tat releases paused polymerase to induce viral expression. Pausing is fundamental for HIV-1, but how it contributes to bursting and stochastic viral reactivation is unclear. Here, we performed single molecule imaging of HIV-1 transcription, and we developed a quantitative analysis method that manages multiple time scales from seconds to days, and that rapidly fits many models of promoter dynamics. We found that RNA polymerases enter a long-lived pause at latent HIV-1 promoters (>20 minutes), thereby effectively limiting viral transcription. Surprisingly and in contrast to current models, pausing appears stochastic and not obligatory, with only a small fraction of the polymerases undergoing long-lived pausing in absence of Tat. One consequence of stochastic pausing is that HIV-1 transcription occurs in bursts in latent cells, thereby facilitating latency exit and providing a rationale for the stochasticity of viral rebounds.

systems biology↗

Alcohol-induced Hsp90 acetylation is a novel driver of liver sinusoidal endothelial dysfunction and alcoholic liver disease

BackgroundIt is unknown whether liver sinusoidal endothelial cells (LSECs) metabolize alcohol. Chronic alcohol consumption decreases endothelial nitric oxide synthase (eNOS)-derived NO production typical of LSEC dysfunction. Heat shock protein 90 (Hsp90) interacts with eNOS to increase its activity. Cytochrome P450 2E1 (CYP2E1) is a key enzyme in alcohol metabolism and facilitates protein acetylation via acetyl-CoA, but its expression in LSECs is unknown. This study investigates alcohol metabolism by LSECs, the mechanism of alcohol-induced LSEC dysfunction and a potential therapeutic approach for alcohol-induced liver injury. MethodsPrimary human, rat and mouse LSECs were used. Histone deacetylase 6 (HDAC6) was overexpressed specifically in liver ECs using an adeno-associated virus (AAV)-mediated gene delivery system to decrease Hsp90 acetylation in ethanol fed mice. ResultsLSECs expressed CYP2E1 and alcohol dehydrogenase 1 (ADH1) and metabolized alcohol. Ethanol induced CYP2E1 in LSECs, but not ADH1. Alcohol metabolism by CYP2E1 increased Hsp90 acetylation and decreased its interaction with eNOS along with a decrease in NO production. A non-acetylation mutant of Hsp90 increased its interaction with eNOS and NO production, whereas a hyper-acetylation mutant decreased NO production, compared with wildtype Hsp90. These results indicate that Hsp90 acetylation is responsible for decreases in its interaction with eNOS and eNOS-derived NO production. Adeno-associated virus 8 (AAV8)-driven HDAC6 overexpression specifically in liver ECs deacetylated Hsp90, restored Hsp90s interaction with eNOS and ameliorated alcohol-induced liver injury in mice. ConclusionRestoring LSEC function is important for ameliorating alcohol-induced liver injury. To this end, blocking acetylation of Hsp90 specifically in LSECs via AAV-mediated gene delivery has the potential to be a new therapeutic strategy.

molecular biology↗

Comprehensive genome sequencing analysis as a promising option in the prenatal diagnosis of fetal structural anomalies: a prospective study.

PurposeGenome sequencing (GS) is a powerful tool for postnatal genetic diagnosis, but relevant clinical studies in the field of prenatal diagnosis are few. We aimed to evaluate the feasibility of GS as a first-line approach in prenatal diagnosis and compare its clinical value with the chromosomal microarray analysis (CMA) plus exome sequencing (ES) sequential testing. MethodsWe applied trio GS ([~]40-fold) in parallel with CMA plus ES to investigate the genetic basis for structural or growth anomalies in 111 fetuses and compared their results. ResultsGS covered all genetic variants in 22 diagnosed cases detected by CMA plus ES, yielding a diagnostic rate of 19.8% (22/110). Moreover, GS provided more comprehensive and precise genetic information than CMA plus ES, revealing twin fetuses with an imbalanced translocation arising from a balanced paternal translocation and one fetus with an extra pathogenic variant in the GJA8 gene, and incidentally identified intrauterine CMV infection in a growth-restricted fetus. ConclusionCompared with CMA plus ES, GS offers a more comprehensive view of the genetic etiology of fetal anomalies and provides clues for nongenetic factors such as intrauterine infection. Our study demonstrates the feasibility of GS as a promising first-line test in prenatal diagnosis.

genomics↗

Analysis of paralogs in target enrichment data pinpoints multiple ancient polyploidy events in Alchemilla s.l. (Rosaceae)

Target enrichment is becoming increasingly popular for phylogenomic studies. Although baits for enrichment are typically designed to target single-copy genes, paralogs are often recovered with increased sequencing depth, sometimes from a significant proportion of loci, especially in groups experiencing whole-genome duplication (WGD) events. Common approaches for processing paralogs in target enrichment datasets include random selection, manual pruning, and mainly, the removal of entire genes that show any evidence of paralogy. These approaches are prone to errors in orthology inference or removing large numbers of genes. By removing entire genes, valuable information that could be used to detect and place WGD events is discarded. Here we use an automated approach for orthology inference in a target enrichment dataset of 68 species of Alchemilla s.l. (Rosaceae), a widely distributed clade of plants primarily from temperate climate regions. Previous molecular phylogenetic studies and chromosome numbers both suggested ancient WGDs in the group. However, both the phylogenetic location and putative parental lineages of these WGD events remain unknown. By taking paralogs into consideration, we identified four nodes in the backbone of Alchemilla s.l. with an elevated proportion of gene duplication. Furthermore, using a gene-tree reconciliation approach we established the autopolyploid origin of the entire Alchemilla s.l. and the nested allopolyploid origin of four major clades within the group. Here we showed the utility of automated tree-based orthology inference methods, previously designed for genomic or transcriptomic datasets, to study complex scenarios of polyploidy and reticulate evolution from target enrichment datasets.

evolutionary biology↗

Caloric Restriction Remodels Energy Metabolic Pathways of Gut Microbiota and Promotes Host Autophagy

Calorie restriction (CR) can improve the metabolic balance of adults and elevate the relative abundance of probiotic bacteria in the gut while promoting longevity. However, the interaction between remodeled intestinal flora and metabolic improvement, as well as the mechanism for probiotic bacterial increase, are still unclear. In this study, using a metabolomics platform, we demonstrate for the first time, that CR leads to increased levels of malate and its related metabolites in biological samples. Next, we investigated the effects of CR on the gut microbial genome and the expression of mRNA related to energy metabolism which revealed a partially elevated TCA cycle and a subsequently promoted glyoxylate cycle, from which large amounts of malate can be produced to further impact malate related pathways in the host liver. Through the identification of key "hungry" metabolites produced by the gut microbiota that function in the promotion of autophagy in the host, further insight has been gained about a functional metabolic network important for both host-microbial symbiosis and maintenance of host health.

systems biology↗