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Results for “comparative transcriptomics”

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PubMed2006

Analysis of bacteria-challenged wild silkmoth, Antheraea mylitta (lepidoptera) transcriptome reveals potential immune genes.

BACKGROUND: In the recent years a strong resemblance has been observed between the insect immune system and the mammalian innate immune mechanisms suggesting their common origin. Among the insects, only the dipterans (Drosophila and various mosquito species) have been widely investigated for their immune responses towards diverse pathogens. In the present study we constructed and analysed the immune transcriptome of the lepidopteran Antheraea mylitta, an economically important Indian tasar silkmoth with a view to unravel the potential immune-related genes and pathways. RESULTS: An expressed sequence tag (EST) library was constructed from mRNA obtained from fat bodies of A. mylitta larvae that had been challenged by infection with Escherichia coli cells. We identified 719 unique ESTs from a total of 1412 sequences so generated. A third of the transcriptome showed similarity with previously characterized immune-related genes that included both the known and putative immune genes. Of the four putative novel defence proteins (DFPs) annotated by PSI-BLAST three showed similarity to extracellular matrix proteins from vertebrates implicated in innate immunity, while the fourth was similar to, yet distinct from, the anti-microbial protein cecropin. Finally, we analysed the expression profiles of 15 potential immune-related genes, and the majority of them were induced more prominently with E. coli compared to Micrococcus luteus. We also identified several unknown proteins, some of which could have probable immune-related functions based on the results of the ProDom analysis. CONCLUSION: The present study has identified many potential immune-related genes in A. mylitta some of which are vertebrate homologues and others are hitherto unreported putative defence proteins. Several genes were present as members of gene families, as has also been observed in other insect species.

Amino Acid Sequence↗

PubMed2025

Verification of biological markers of subacute cutaneous lupus erythematosus via TMT labelling proteomics combined with transcriptome data.

OBJECTIVE: This study aimed to investigate biological markers in subacute cutaneous lupus erythematosus (SCLE). METHODS: The tandem mass tag (TMT)-labelling proteomics method was used to explore differentially expressed proteins between SCLE lesions and normal skin tissues. The differences in transcriptomic data between SCLE tissues and normal skin tissues were analysed from the GEO database (GSE81071, GSE109248 and GSE112943). The differences in transcriptomic data from peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) and normal controls were analysed (GSE81622 and GSE154851). The 35 healthy controls, 30 SCLE patients, 35 SLE patients and 30 lupus nephritis (LN) patients were diagnosed and enrolled. The serum expression levels of IFI44 and EPSTI1 were detected. Data were presented as the mean ± standard deviation or frequency and were analysed using Student's t-test, Chi-square test and one-way ANOVA between the groups. Receiver operating characteristic (ROC) curves were used to analyse the clinical efficacy of IFI44 and EPSTI1 in distinguishing SCLE from SLE. RESULTS: In a comparative analysis of SCLE lesions and normal skin tissues, proteomics studies identified 376 proteins that exhibited significant differential expression. In GO and KEGG analyses, the enriched terms mainly included the interferon-gamma-mediated signalling pathway (p < .001), immune receptor activity (p < .001) and cell adhesion molecules (p < .001). The top 10 hub genes were screened in SCLE as follows: CD8A, CXCL10, IFI44, CD7, CCL5, TLR4, EPSTI1, ISG15, KLRD1 and SELL using Cytoscape (3.10.1) software. The 15 common proteins/genes between proteomics and three datasets results were found, including CXCL10, OAS1, DDX60L, CFB, IFI6, HERC6, IFI44L, GBP1, EPSTI1, OAS2, CXCL11, TYMP, IFI44, ISG15 and IFIT3. The 61 differentially expressed genes in GSE81622 and the top 100 differentially expressed genes in GSE154851, alongside the 15 identified genes described above through Venn diagram analysis. Four common genes, IFI44L, IFI44, EPSTI1 and OAS1, were identified. Two common genes, IFI44 and EPSTI1, were found in hub genes from the proteomics results. The serum levels of IFI44 and EPSTI1 in LN were significantly higher than those in SLE patients (p < .05). ROC curve analysis demonstrated that serum levels of IFI44 and EPSTI1 could differentiate SCLE from SLE with an area under the curve (AUC) of 0.898 and 0.847, respectively. CONCLUSIONS: The IFI44 and EPSTI1 proved to be closely involved in the progression from SCLE to SLE, and can represent new candidate diagnostic molecular markers of occurrence and progression of SCLE.

Humans↗

PubMed2026

Haplotype-resolved 3D genome maps reveal RNAPII-mediated allelic regulation in hybrid rice.

To understand how the two parental genomes coordinate transcription in hybrids, chromatin architecture must be resolved at the haplotype level. Here, using phased Bridge-Linker Hi-C, we reconstructed a haplotype-resolved three-dimensional (3D) genome of the elite hybrid rice (Oryza sativa) line Shanyou 63 (SY63). We identified extensive allele-specific chromatin conformations. Furthermore, we generated allele-resolved RNAPII ChIA-PET maps and phased transcriptomes to explore how chromatin interactions contribute to allelic regulation. Although maternal and paternal homologs share broadly similar chromatin features, we detected widespread haplotype-biased RNAPII binding and chromatin looping at high resolution. These allele-specific RNAPII-mediated contacts were significantly associated with biased expression. Stronger RNAPII binding on one haplotype promoted the formation of long-range regulatory loops with distal genes, thereby contributing to allele-biased transcription at a subset of loci, even when promoter-proximal RNAPII occupancy was comparable between alleles. These results demonstrate that subtle differences in RNAPII engagement and 3D regulatory wiring between parental haplotypes can reshape transcriptional output in hybrids, providing new insights into the mechanisms underlying the allelic regulation of gene expression.

Allele-specific chromatin interactions↗

PubMed2002

Estradiol differentially regulates lipocalin-type prostaglandin D synthase transcript levels in the rodent brain: Evidence from high-density oligonucleotide arrays and in situ hybridization.

Microarrays comprise an efficient approach to discovering large numbers of differentially expressed mRNA transcripts in the CNS resulting from changes in hormonal milieu. We used high-density oligonucleotide microarrays to examine the short- and long-term actions of estradiol (E(2)) on the transcriptomes from the medial basal hypothalamus and other brain regions of E(2)-treated (10 microg) adult female mice. Our results have revealed several unanticipated gene regulations. Most striking is lipocalin prostaglandin D(2) synthase (L-PGDS), which catalyzes the conversion of prostaglandin (PG) H(2) to PGD(2), a neuromodulator involved in a variety of functions, including sleep, pain, and odor responses. In situ hybridization revealed significant increases in L-PGDS expression in the arcuate and ventromedial nucleus of the medial basal hypothalamus compared with vehicle controls. The magnitude of these changes is approximately 2-fold and suggests a modulatory role for PGD(2) in E(2)-controlled neuroendocrine secretions and behaviors. Surprisingly, L-PGDS gene expression is reduced 2-fold after E(2) treatment in the ventrolateral preoptic area (VLPO), the suspected site of action for the sleep-promoting effects of PGD(2). Finally, whereas L-PGDS has been reported to be expressed primarily in oligodendrocytes of the adult rodent brain, we demonstrate, immunocytochemically, that L-PGDS is also expressed in a population of VLPO neurons. Thus, our data suggest the intriguing possibility that E(2) modulation of L-PGDS plays a role in the regulation of sleep-wake states through hitherto unknown mechanisms in VLPO neurons and through hormone-dependent neuronal-glial cooperation.

Animals↗

PubMed2006

Distorted relation between mRNA copy number and corresponding major histocompatibility complex ligand density on the cell surface.

The major histocompatibility complex (MHC) presents peptides derived from degraded cellular proteins to T-cells and is thus crucial for triggering specific immune responses against viral infections or cancer. Up to now, there has been no evidence for a correlation between levels of mRNA (the "transcriptome") and the density of MHC-peptide complexes (the "MHC ligandome") on cells. Because such dependences are of intrinsic importance for the detailed understanding of translation efficiency and protein turnover and thus for systems biology in general and for tumor immunotherapy in practical application, we quantitatively analyzed the levels of mRNA and corresponding MHC ligand densities in samples of renal cell carcinomas and their autologous normal kidney tissues. Relative quantification was carried out by gene chip analysis and by stable isotope peptide labeling, respectively. In comparing more than 270 pairs of gene expression and corresponding peptide presentation ratios, we demonstrate that there is no clear correlation (r = 0.32) between mRNA levels and corresponding MHC peptide levels in renal cell carcinoma. A significant number of peptides presented predominantly on tumor or normal tissue showed no or only minor changes in mRNA expression levels. In several cases, peptides could even be identified despite the virtual absence of the respective mRNA. Thus we conclude that a majority of epitopes from tumor-associated antigens will not be found in approaches based mainly on mRNA expression studies as mRNA expression reflects a distorted picture of the situation on the cell surface as visible for T-cells.

Amino Acid Sequence↗

PubMed2006

Rampant polyuridylylation of plastid gene transcripts in the dinoflagellate Lingulodinium.

Dinoflagellate plastid genes are believed to be encoded on small generally unigenic plasmid-like minicircles. The minicircle gene complement has reached saturation with an incomplete set of plastid genes (18) compared with typical functional plastids (60-200). While some of the missing plastid genes have recently been found in the nucleus, it is still unknown if additional genes, not located on minicircles, might also contribute to the plastid genome. Sequencing of tailed RNA showed that transcripts derived from the known minicircle genes psbA and atpB contained a homogenous 3' polyuridine tract of 25-40 residues. This unusual modification suggested that random sequencing of a poly(dA) primed cDNA library could be used to characterize the plastid transcriptome. We have recovered only 12 different polyuridylylated transcripts from our library, all of which are encoded on minicircles in several dinoflagellate species. The correspondence of all polyuridylylated transcripts with previously described minicircle genes thus supports the dinoflagellate plastid as harbouring the smallest genome of any functional chloroplast. Interestingly, northern blots indicate that the majority of transcripts are modified, suggesting that polyuridylylation is unlikely to act as a degradation signal as do the heterogeneous poly(A)-rich extensions of transcripts in cyanobacteria and other plastids.

3' Untranslated Regions↗

PubMed2006

Complex alternative splicing of the myelin oligodendrocyte glycoprotein gene is unique to human and non-human primates.

Myelin/oligodendrocyte glycoprotein (MOG) is a minor integral membrane protein specific to CNS myelin, encoded by a gene located in the major histocompatibility complex. MOG is an highly encephalitogenic autoantigen and a target for autoaggressive immune responses in CNS inflammatory demyelinating diseases. We performed transcriptomic analyses for a gene expressed only in mammalian CNS, myelin oligodendrocyte glycoprotein (MOG). Complex splicing patterns were exclusively found in primates and not in mice, unlike patterns found for other myelin protein genes. In addition to those shared with rodents, these multiple MOG isoforms likely support functions unique to the primate order, in particular maintenance of myelin structure, intracellular signaling, and modulation of CNS autoimmunity via exposure of specific MOG determinants. Developmentally, in human brain the splice variants of MOG appear at a late stage compared to the major isoform, coincidental with myelination and myelin maturation, unlike other myelin proteins. These findings are discussed within the framework of a biological basis for phenotype diversity in recent mammalian evolution and for the notoriously variable clinical expression of diseases such as multiple sclerosis.

Alternative Splicing↗

PubMed2003

Chromosomal distribution of the human cardiovascular transcriptome.

On the basis of previous observations in chromosomes 21 and 22, we hypothesize that there is a tissue-specific organization of cardiovascular gene transcripts in the human genome. To examine the distribution of heart-derived transcripts, we assigned a nonredundant set of 4628 fetal and 3574 adult known and uncharacterized cardiovascular expressed-sequence tags (cvESTs) to 5-Mb chromosomal 'windows' on the basis of publicly available sequence mapping data. On a whole-genome level (36,617 genes), chromosome 17 (19.2% in fetal, 16.5% in adult) contained the highest proportion of cvESTs, whereas chromosome Y (2.0% in fetal and adult) contained the lowest. In total, 50 of the 639 windows contained a significantly higher proportion of cvESTs (P < 0.003) compared with the genome-wide cvEST gene density, particularly on gene-dense chromosomes (that is, 17, 19, 22) as opposed to gene-rich chromosomes (for example, 1, 2, 11). This report provides insight into a possible role for complex tissue-specific gene regulation in the human genome.

Cardiovascular System↗

PubMed2003

Determination of the transcriptome of Vibrio cholerae during intraintestinal growth and midexponential phase in vitro.

Vibrio cholerae is the etiologic bacterial agent of cholera, a severe diarrheal disease endemic in much of the developing world. The V. cholerae genome contains 3,890 genes distributed between a large and a small chromosome. Although the large chromosome encodes the majority of recognizable gene products and virulence determinants, the small chromosome carries a disproportionate number of hypothetical genes. Thus, little is known about the role of the small chromosome in the biology of this organism or other Vibrio species. We have used the rabbit ileal loop model of V. cholerae infection to obtain in vivo-grown cells under near midexponential conditions in the small-intestinal environment. We compared the global transcriptional pattern of these in vivo-grown cells to those grown to midexponential phase in rich medium under aerobic conditions. Under both conditions, the genes showing the highest levels of expression reside primarily on the large chromosome. However, a shift occurs in vivo that results in many more small chromosomal genes being expressed during growth in the intestine. Our analysis further suggests that nutrient limitation (particularly iron) and anaerobiosis are major stresses experienced by V. cholerae during growth in the rabbit upper intestine. Finally, relative to in vitro growth, the intestinal environment significantly enhanced expression of several virulence genes, including those involved in phenotypes such as motility, chemotaxis, intestinal colonization, and toxin production.

Animals↗

PubMed2024

Transcriptome analysis reveals that PRV XJ delgE/gI/TK protects against intestinal damage in nose-dropping-infected mice by regulating ECM-ITGA/ITGB-P-FAK.

Pseudorabies virus (PRV) is an ideal model for mechanistic investigations into α-herpesvirus. The neurotropism and latent infection of PRV have been extensively studied. Apart from neurological symptoms, diarrhea caused by PRV infection is also an essential cause of mortality in newborn and weaned piglets. However, little research has been done on PRV invasion of the gut. To fill this gap, a nasal drip PRV-infection mouse model was developed, consisting of three groups: the challenged group (Group A), the immunization-challenged group (Group B), and a mock group (Group C). The results showed that immunization with PRV XJ delgE/gI/TK successfully prevented intestinal damage caused by PRV drop-nose infection. Subsequently, intestines were collected for transcriptional analysis. Differentially expressed genes analysis revealed that PRV XJ delgE/gI/TK was effective in reducing the organismal intestinal transcriptional activity caused by PRV. The Group A vs Group C and Group A vs Group B had similar Kyoto Encyclopedia of Genes and Genomes (KEGG)-enriched signaling pathways and the differentially expressed genes were primarily enriched in pathways, such as cell adhesion molecules, focal adhesion kinase, and actin cytoskeleton regulation. Notably, transcriptome analysis indicated that genes associated with the focal adhesion kinase (FAK) signaling pathway (ECM-ITGA/ITGB-p-FAK) were significantly more highly expressed in Group A than in Group B and Group C. The results of quantitative real-time PCR (RT-qPCR) and western blotting were consistent with KEGG analysis. Therefore, we hypothesized that PRV promotes self-infection through activation of the ECM-ITGA/ITGB-p-FAK signaling pathway and that PRV XJ delgE/gI/TK immunization could attenuate the intestinal damage caused by PRV by inhibiting the activation of this pathway.IMPORTANCEPseudorabies virus (PRV) poses a significant threat to the swine industry and public health due to its ability to infect multiple species, including humans, leading to substantial economic losses and potential health risks. This study addresses a critical gap in understanding the impact of PRV infection on the gut, which has been less explored compared to its neurological effects. By developing a drip-nose PRV-infection mouse model, the research indicated that PRV might promote self-infection through activation of the ECM-ITGA/ITGB-p-FAK signaling pathway, and PRV XJ delgE/gI/TK immunization effectively prevents intestinal damage by significantly reducing the expression of genes in the ECM-ITGA/ITGB-p-FAK signaling pathway. The research has important implications for the swine industry and public health by contributing to the development of better vaccines and treatments, ultimately helping to control PRV and prevent its cross-species transmission.

Animals↗

PubMed2004

Overexpression and affinity chromatography purification of the Type III restriction endonuclease EcoP15I for use in transcriptome analysis.

The Type III restriction endonuclease EcoP15I is a multifunctional hetero-oligomeric enzyme that recognizes the non-symmetric DNA sequence 5'-CAGCAG. For efficient cleavage, EcoP15I needs the interaction with two copies of the recognition sequence that have to be inversely oriented in the DNA double strand. The enzyme cuts the upper DNA strand 25-26 bp and the lower DNA strand 27-28 bp, respectively, downstream of the recognition sequence-a distinct feature that makes the enzyme particularly valuable for gene expression profiling methods relying on the SAGE procedure (Matsumura et al., PNAS 100, 15718, 2003). Because the broader use of this transcriptome analysis method requires the availability of larger amounts of restriction endonuclease EcoP15I and the enzyme is not commercially available, we have cloned the genes coding for the EcoP15I restriction endonuclease into pQE-16 plasmid vector that provides the enzyme with a C-terminal 6xHis-tag. After Ni-NTA affinity chromatography and ion exchange chromatography on heparin sepharose, we obtained 5mg homogeneous EcoP15I per gram cell pellet within 1-2 day(s). Moreover, the C-terminally 6xHis-tagged EcoP15I restriction endonuclease shows comparable enzymatic activity as the untagged enzyme.

Amino Acid Sequence↗

PubMed2006

Evaluation of RNA-binding specificity of aminoglycosides with DNA microarrays.

We have developed methods for using DNA array technology to probe the entire transcriptome to determine the RNA-binding specificity of ligands. Two methods were investigated. In the first method, the RNA-binding aminoglycoside antibiotic tobramycin was covalently linked to magnetic beads. The beads were bound to human liver mRNA and washed, and specifically bound RNA was eluted, amplified, and analyzed with DNA array technology. A small number of genes were found to bind specifically to the tobramycin beads. In the second method, the aminoglycoside ligand was added directly to the array hybridization reaction, and the signal was compared with a control experiment in the absence of ligand. The aminoglycosides were found to interfere with a small percentage of all hybridization events. These methods differ from traditional DNA array experiments in that the readout is a direct measure of the interaction between mRNA and a ligand, rather than an indirect measure of effect on expression. We expect that the results will lead to the discovery of new aminoglycoside-binding RNA motifs and may also have relevance toward understanding and overcoming the side effects observed with these antibiotics in the clinic.

Animals↗

PubMed2006

Genome-wide expression studies of atherosclerosis: critical issues in methodology, analysis, interpretation of transcriptomics data.

During the past 6 years, gene expression profiling of atherosclerosis has been used to identify genes and pathways relevant in vascular (patho)physiology. This review discusses some critical issues in the methodology, analysis, and interpretation of the data of gene expression studies that have made use of vascular specimens from animal models and humans. Analysis of gene expression studies has evolved toward the genome-wide expression profiling of large series of individual samples of well-characterized donors. Despite the advances in statistical and bioinformatical analysis of expression data sets, studies have not yet fully exploited the potential of gene expression data sets to obtain novel insights into the molecular mechanisms underlying atherosclerosis. To assess the potential of published expression data, we compared the data of a CC chemokine gene cluster between 18 murine and human gene expression profiling articles. Our analysis revealed that an adequate comparison is mainly hindered by the incompleteness of available data sets. The challenge for future vascular genomic profiling studies will be to further improve the experimental design, statistical, and bioinformatical analysis and to make data sets freely accessible.

Animals↗

PubMed2006

Whole genome expression profiling of the medial and lateral substantia nigra in Parkinson's disease.

We have used brain tissue from clinically well-documented and neuropathologically confirmed cases of sporadic Parkinson's disease to establish the transcriptomic expression profile of the medial and lateral substantia nigra. In addition, the superior frontal cortex was analyzed in a subset of the same cases. DNA oligonucleotide microarrays were employed, which provide whole human genome coverage. A total of 570 genes were found to be differentially regulated at a high level of significance. A large number of differentially regulated expressed sequence tags were also identified. Levels of mRNA sequences encoded by genes of key interest were validated by means of quantitative real-time polymerase chain reaction (PCR). Comparing three different normalization procedures, results based on the recently published GeneChip Robust Multi Array algorithm were found to be the most accurate predictor of real-time PCR results. Several new candidate genes which map to PARK loci are reported. In addition, the DNAJ family of chaperones is discussed in the context of Parkinson's disease pathogenesis.

Aged↗

PubMed2005

Use of 'Omic' technologies to study humans exposed to benzene.

'Omic' technologies include genomics, transcriptomics (gene expression profiling), proteomics and metabolomics. We are utilizing these new technologies in an effort to develop novel biomarkers of exposure, susceptibility and response to benzene. Advances in genomics allow one to study hundreds to thousands of single nucleotide polymorphisms simultaneously on small quantities of DNA using array-based technologies. We are currently utilizing these technologies to examine genetic variation in pathways relating to biotransformation, DNA repair, folate metabolism and immune response with the goal of finding biomarkers of susceptibility to benzene hematotoxicity. Transcriptomics is used to measure the full complement of activated genes, mRNAs or transcripts in a particular tissue at a particular time typically using microarray technology. We have applied microarrays to the study of global gene expression in the peripheral blood cells of benzene-exposed workers. More than 100 genes were identified as being potentially differentially expressed, with genes related to apoptosis and immune function being the most significantly affected. Initial studies employing proteomics have also shown that several proteins are altered in the serum of exposed compared to control subjects and these proteins are potential biomarkers of benzene exposure. Omic technologies therefore have significant potential in generating novel biomarkers of exposure, susceptibility and response to benzene.

Air Pollutants, Occupational↗

PubMed2005

SuperSAGE combined with PCR walking allows global gene expression profiling of banana (Musa acuminata), a non-model organism.

Super-serial analysis of gene expression (SuperSAGE) was used to characterize, for the first time, the global gene expression pattern in banana (Musa acuminata). A total of 10,196 tags were generated from leaf tissue, representing 5,292 expressed genes. Forty-nine tags of the top 100 most abundantly expressed transcripts were annotated by homology to cDNA or EST sequences. Typically for leaf tissue, analysis of the transcript profiles showed that the majority of the abundant transcripts are involved in energy production, mainly photosynthesis. However, the most abundant tag was derived from a type 3 metallothionein transcript, which accounted for nearly 3% of total transcripts analysed. Furthermore, the 26-bp long SuperSAGE tags were applied in 3'-rapid amplification of cDNA ends (3'RACE) for the identification of unknown tags. In combination with thermal asymmetric interlaced PCR (TAIL-PCR), this allowed the recovery of a full gene sequence of a novel NADPH:protochlorophyllide oxidoreductase, the key enzyme in chlorophyll biosynthesis. SuperSAGE in conjunction with 3'RACE and TAIL-PCR will be a powerful tool for transcriptomics of non-model, but otherwise important organisms.

Base Sequence↗

PubMed2004

Candida albicans biofilms: a developmental state associated with specific and stable gene expression patterns.

Like many bacteria, yeast species can form biofilms on several surfaces. Candida albicans colonizes the surfaces of catheters, prostheses, and epithelia, forming biofilms that are extremely resistant to antifungal drugs. We have used transcript profiling to investigate the specific properties of C. albicans biofilms. Biofilm and planktonic cultures produced under different conditions of nutrient flow, aerobiosis, or glucose concentration were compared by overall gene expression correlation. Correlation was much higher between biofilms than planktonic populations irrespective of the growth conditions, indicating that biofilm populations formed in different environments display very similar and specific transcript profiles. A first cluster of 325 differentially expressed genes was identified. In agreement with the overrepresentation of amino acid biosynthesis genes in this cluster, Gcn4p, a regulator of amino acid metabolism, was shown to be required for normal biofilm growth. To identify biofilm-related genes that are independent of mycelial development, we studied the transcriptome of biofilms produced by a wild-type, hypha-producing strain and a cph1/cph1 efg1/efg1 strain defective for hypha production. This analysis identified a cluster of 317 genes expressed independently of hypha formation, whereas 86 genes were dependent on mycelial development. Both sets revealed the activation of the sulfur-amino acid biosynthesis pathway as a feature of C. albicans biofilms.

Amino Acids, Sulfur↗

PubMed2024

Muscle Tissue Transcriptome of Idiopathic Inflammatory Myopathy Reflects the Muscle Damage Process by Monocytes and Presence of Skin Lesions.

OBJECTIVE: We aim to investigate transcriptomic and immunophenotypic features of muscle specimens from patients with idiopathic inflammatory myopathy (IIM). METHODS: Bulk RNA-sequencing was performed on muscle biopsy samples from 16 patients with dermatomyositis (DM) and 9 patients with polymyositis (PM). Seven tested positive for anti-aminoacyl transfer RNA synthetase antibodies in the patients with DM (ARS-DM). We conducted weighted gene coexpression network analysis (WGCNA), differentially expressed gene (DEG) analysis, and gene set variation analysis to assess contributions of specific pathways. Cell proportions in muscle specimens were estimated using a deconvolution approach. RESULTS: WGCNA revealed significant positive correlations between serum creatine kinase (CK) levels and gene modules involved in cellular respiration, phagocytosis, and oxidative phosphorylation (OXPHOS). Significant positive correlations were also observed between CK levels and proportions of CD16-positive and negative monocytes and myeloid dendritic cells. Notably, patients with DM demonstrated enrichment of complement and interferon-α and γ pathway genes compared with those with PM. Furthermore, ARS-DM demonstrated a higher proportion of Th1 cells and DEGs related to OXPHOS. Additionally, serum Krebs von den Lungen-6 levels correlated with gene modules associated with extracellular matrix and the transforming growth factor-β signaling pathway. CONCLUSION: Our study highlights a significant involvement of monocytes in muscle damage and delineates pathologic differences among IIM subtypes. DM was characterized by complement and interferon-α and γ signaling, whereas ARS-DM was associated with OXPHOS. Distinctive gene expression variations in muscle specimens suggest that different pathologic mechanisms underlie muscle damage in each IIM phenotype.

Humans↗