Comprehensive Gene Expression Profiling Research Articles

The molecular and cellular landscape of hypertrophic cardiomyopathy phenotypes: transition from obstructive to end-stage heart failure.

Hypertrophic cardiomyopathy (HCM) is a myocardial disorder which commonly presents as an obstructive or end-stage disease. This study aims to investigate the transcriptomic changes related to cardiac cell-specific expression profiles that underpin the molecular transition between the HCM phenotypes. This study utilizes bioinformatics meta-analysis to integrate independent datasets to generate a comprehensive gene expression profile of obstructive HCM and end-stage HCM phenotypes compared to donor hearts. Gene set enrichment and cellular deconvolution were applied to identify ontologies and pathways related to each phenotype and to enumerate cell abundances. The intersection between cell lineage genes and meta-genes was identified to explore the cellular contribution to the phenotypic molecular signatures. Meta-analysis revealed, enhanced muscle function and myocardial remodeling, alongside impaired immune and inflammatory processes in obstructive HCM. In contrast, enriched tissue matrix remodeling pathways and altered metabolic and signaling cascades were identified in end-stage HCM, indicating a shift towards cellular dysfunction and loss of homeostasis. These molecular profiles were associated with an altered cellular landscape, with increased cardiomyocytes and lower immune cell populations in obstructive samples but increased fibroblasts and smooth muscle cells in end-stage HCM, implicating extensive tissue remodeling. This study provides novel insights into the cellular contributions of contractile, immune, homeostatic, and vascular alterations underpinning each of the HCM phenotypes. KEY MESSAGES: HCM phenotypes are characterized by distinct molecular and cellular profiles. Obstructive HCM has an enriched contractile profile underpinned by an expanded cardiomyocyte population. End-stage HCM shifts the cellular profile towards extracellular and vascular remodeling.

Genomic insights into fibrinogen-related proteins and expression analysis in the Pacific white shrimp, Litopenaeusvannamei.

Fibrinogen-related domain (FReD) containing proteins are an evolutionarily conserved immune gene family characterized by the C-terminal fibrinogen (FBG) and diverse N-terminal domains. To understand the complexity of this family in crustaceans, we performed genome screening and identified 43 full-length FReDs encoding genes in Litopenaeus vannamei. Structural classification analysis revealed these putative FReDs could be divided into six types, including two reported types (LvFReDI and II) and four new types (LvFReDIII-VI). Sequence and phylogenetic analysis showed that FBG domains were highly conserved throughout and phylogeny clusters correlated strongly with gene type. We analyzed the temporal and spatial expression patterns of LvFReD genes based on the transcriptomes of developmental stages, adult tissues or pathogen infected tissues of L. vannamei. Most LvFReDs were expressed from larval in membrane stage, and exhibited tissue-specific expression patterns and immune-responsive transcription after challenge with bacteria or virus. Further time-course expression analysis suggested that LvFReDII genes with additional coiled-coil region were more sensitive to pathogens than LvFReDI genes. Our findings provided comprehensive gene sequence resources and expression profiles of FReD genes in shrimp, which give insights into clarifying the diversity and function of these genes in crustaceans.

Heterogeneity of cancer-associated fibroblast subpopulations in prostate cancer: Implications for prognosis and immunotherapy.

Prostate cancer stands as the second most common malignancy among men, notorious for its intricate heterogeneity, especially evident in metastatic disease. This complexity presents substantial challenges in treatment efficacy and patient prognosis. This study endeavors to elucidate the multifaceted roles of cancer-associated fibroblasts within the tumor microenvironment of prostate cancer, with a focus on their implications for disease prognosis and the potential for novel immunotherapeutic strategies. Leveraging advanced single-cell RNA sequencing technology, we meticulously characterized the diverse CAF subpopulations within prostate cancer samples. Our analysis identified four predominant subsets: C0 IER2+, C1 ABCA8+, C2 ABI3BP+, and C3 MEOX2+. We conducted comprehensive gene expression profiling to construct a robust prognostic model reflecting the clinical relevance of these subpopulations. C1 ABCA8+ fibroblasts demonstrated heightened proliferative activity, underscoring their pivotal role in fostering tumor growth and metastasis via intricate signaling pathways. In vitro experiments verified that the T transcription factor NFAT5 of C1 ABCA8+ fibroblasts subpopulation was knocked down in LNCaP clone FGC and 22Rv1 cell lines, which was closely related to the proliferation of PC. Moreover, we identified key genes linked to patient outcomes and immune landscape alterations, reinforcing the prognostic significance of CAF characteristics in this context. This investigation illuminates the critical potential of targeting CAFs to augment immunotherapeutic approaches in prostate cancer. Our findings contribute to a deeper understanding of the TME's complexity, advocating for further exploration into CAF-targeted therapies aimed at enhancing treatment responses and ultimately improving patient outcomes.

Comprehensive Identification and Expression Profiling of Lipoxygenase Genes in Sweet Cherry During Fruit Development

Lipoxygenase (LOX) is involved in the oxidation of fatty acids in plants and is a ubiquitous oxygenase that plays an important role in the process of plant resistance to adversity. In this study, the LOX gene family in the sweet cherry genome was identified by bioinformatics methods, the chromosomal mapping of different LOX genes was carried out, and the homology alignment and functional domain analysis of the encoded proteins were performed. The results showed that there were nine LOX gene sequences in the sweet cherry LOX gene family, and the subcellular localization was mainly located in the cytoplasm, chloroplast, or plasma membrane, and was concentrated on chromosomes 1, 2, 3, 4, 6, and 8. During the ripening process of sweet cherry fruits, the LOX gene family showed five different expression patterns, the expression peak of different LOX genes reached the peak of expression at a specific development period, all LOX genes jointly promoted the growth and development of fruits, the enzyme activities of LOX in different varieties of early and late ripening cherries exhibited great differences during the development process, and the results of volatile content in the later stages also showed that different varieties of cherries had their specificity. The results of this study provide a theoretical basis for further revealing the specific functions of LOX gene family members in sweet cherry.

Comprehensive analysis of housekeeping genes, tissue-specific genes, and dynamic regulation across developmental stages in pearl millet

BackgroundPearl millet (Pennisetum glaucum (L.) R. Br.) is a vital cereal crop, predominantly cultivated in arid and semi-arid regions of Asia and Africa. It serves as a staple food for millions, while also being utilized as forage and an energy crop. The crop’s resistance to heat and drought, coupled with its high biomass, positions it as a promising candidate for climate-resilient agriculture. A detailed understanding of its gene expression patterns across various tissues and developmental stages is essential for enhancing its yield and quality. This study aims to fill this knowledge gap by employing RNA-seq to identify housekeeping genes (HKGs) and tissue-specific genes (TSGs) in pearl millet.ResultsOur analysis of RNA-seq data from nine tissues (seed, germ, radicle, leaf, root, tillering tissue, stem, spike, and grain) across eight developmental stages in pearl millet accession Tifleaf3 revealed a comprehensive gene expression profile. We identified 461 HKGs that exhibited stable expression across all tissues and stages, providing robust internal references for RT-qPCR. Additionally, 8091 TSGs were discovered, many of which showed distinctive expression patterns in tissues such as spike, stem, and leaf. Functional enrichment analysis of these genes using GO and KEGG pathways highlighted their roles in key biological processes and pathways, indicating their potential in crop trait enhancement. Protein-protein interaction networks constructed for stem and leaf tissues further illuminated the regulatory mechanisms underlying the transition from vegetative to reproductive growth stages.ConclusionThis study presents a detailed transcriptomic landscape of pearl millet, identifying a set of HKGs and TSGs that are crucial for understanding the molecular basis of its growth and development. We provided valuable options for transcript normalization and crucial targets for exploring gene function for the plant growth and development in pearl millet. The insights gained from this work are instrumental for breeding programs aimed at enhancing the productivity of pearl millet, thereby contributing to food and energy security.

Effect of organic selenium on performance and gill transcriptome of whiteleg shrimp Penaeus vannamei.

Shrimp gill health is an indicator of their overall health and environmental stress, as gills are in direct contact with the external environment. Organic selenium (OS), known for its high bioavailability and antioxidant properties, potentially enhances shrimp growth, survival, and immune responses. This study investigated the physiological features through comprehensive gill gene expression profiling and growth parameters by incorporating OS into Penaeus vannamei diets. Two OS-containing products, AlkoSel (AS) and SelPlex (SL), were supplied to the diet of P. vannamei (0.90 ± 0.05g body weight, 4.54 ± 0.5cm length) at a dose of 0.4mg Se kg- 1 ration in the final feed. Three groups were organized: an AS-fed group, an SL-fed group, and a control (C) group without additives. After a one-month feeding trial, performance indices (PI) were assessed and RNA-Seq analysis was conducted. The PI revealed that both OS products had similar growth-stimulating effects, with no significant differences between the two groups. However, both groups showed significant improvement compared to the C-group. The P. vannamei gill transcriptome was strongly impacted by the two OS products, with several KEGG pathways implicated in their metabolic mechanisms. Pathways related to energy metabolism, carbohydrate metabolism, lipid metabolism, non-specific immunity, and antioxidative responses were significant in regulating the addition of AS and SL to P. vannamei diets. While SL had some higher additive effects on the gene expression profile than AS, OS from either product is an essential micronutrient that promotes growth, normal metabolic activities, and good gill health in P. vannamei during the early feeding period.

Cross-species single-cell analysis reveals divergence and conservation of peripheral blood mononuclear cells

BackgroundSingle-cell transcriptome sequencing (scRNA-seq) has revolutionized the study of immune cells by overcoming the limitations of traditional antibody-based identification and isolation methods. This advancement allows us to obtain comprehensive gene expression profiles from a diverse array of vertebrate species, facilitating the identification of various cell types. Comparative immunology across vertebrates presents a promising approach to understanding the evolution of immune cell types. In this study, we conducted a comparative transcriptome analysis of peripheral blood mononuclear cells (PBMCs) at the single-cell level across 12 species.ResultsOur findings shed light on the cellular compositional features of PBMCs, spanning from fish to mammals. Notably, we identified genes that exhibit vertebrate universality in characterizing immune cells. Moreover, our investigation revealed that monocytes have maintained a conserved transcriptional regulatory program throughout evolution, emphasizing their pivotal role in orchestrating immune cells to execute immune programs.ConclusionsThis comprehensive analysis provides valuable insights into the evolution of immune cells across vertebrates.

Fusion of breast cancer MCF-7 cells with mesenchymal stem cells rearranges interallelic gene expression and enhances cancer malignancy

Fusion among normal cells is tightly regulated and required for the developmental processes of an organism. Cancer cell fusion appears relatively rare but is associated with generating new hybrid cancer cells with aggressive properties. However, it remains unclear how cancer cells acquire aggressiveness via cell fusion. Here, we report changes in cell proliferative capacity, cell motility, anticancer drug resistance, and gene expression profiles when fusing human MCF-7 breast cancer cells and mesenchymal stem cells (MSCs). The fused cells were established using envelopes of a hemagglutinating virus of Japan, which increased cell proliferation, motility, and drug resistance. Comprehensive gene expression profile analysis revealed that the fused cells expressed higher levels of glycolysis-related genes than their parental cells. In fact, the fused cells relied more on glycolysis for ATP production (Warburg effect). HIF1A, which induces the expression of glycolysis-related genes, was upregulated in fused cells compared to MCF-7 cells. Allele-specific expression analysis of the fused cells indicated that MSC allele-derived HIF1A efficiently induces the expression of glycolysis-related genes in the MCF-7 allele. These findings indicate that the reorganization of gene expression by combining MSCs and MCF-7 alleles resulted in the predominant expression of glycolysis-related genes and increased malignancy in the fused cells.

RNA sequencing reveals molecular mechanisms of endometriosis lesion development in mice.

Understanding of molecular mechanisms contributing to the pathophysiology of endometriosis, and upstream drivers of lesion formation, remains limited. Using a C57Bl/6 mouse model in which decidualized endometrial tissue is injected subcutaneously in the abdomen of recipient mice, we generated a comprehensive profile of gene expression in decidualized endometrial tissue (n=4), and in endometriosis-like lesions at Day 7 (n=4) and Day 14 (n=4) of formation. High-throughput mRNA sequencing allowed identification of genes and pathways involved in the initiation and progression of endometriosis-like lesions. We observed distinct patterns of gene expression with substantial differences between the lesions and the decidualized endometrium that remained stable across the two lesion timepoints, and showed similarity to transcriptional changes implicated in human endometriosis lesion formation. Pathway enrichment analysis revealed several immune and inflammatory response-associated canonical pathways, multiple potential upstream regulators, and involvement of genes not previously implicated in endometriosis pathogenesis, including IRF2BP2 and ZBTB10, suggesting novel roles in disease progression. Collectively, the provided data will be a useful resource to inform research on the molecular mechanisms contributing to endometriosis-like lesion development in this mouse model.

Physiological and Transcriptomic Characterization of Rice Genotypes under Drought Stress

Drought is a primary abiotic stress that inhibits rice (Oryza sativa L.) growth and development, and during the reproductive stage it has a negative impact on the rice seed-setting rate. This research study examined two rice lines, La-96 (drought sensitive) and La-163 (drought resistant), for drought stress treatment (with soil moisture at 20% for 7 days) and control (normal irrigation and kept soil moisture ≥40%). To elucidate the photosynthesis and molecular mechanisms underlying drought tolerance in rice, leaf photosynthetic traits and transcriptome sequencing were used to compare differences between two contrasting recombinant inbred lines (RIL) during drought and subsequent recovery at the booting stage. The rice line La-96 showed a significant decrease in seed-setting rate after being treated for seven days’ drought stress (from 86.64% to 22.75%), while La-163 was slightly affected (from 89.04% to 79.33%). The photosynthetic activities of both lines significantly decreased under the drought treatment, and these traits of La-163 recovered to a comparable level with the control after three days of rewatering. The transcriptome of both lines in three treatments (the control, drought stress, and subsequent recovery) were tested, and a total of 16,051 genes were identified, among which 10,566 genes were differentially expressed in various treatments and rice lines. Comprehensive gene expression profiles revealed that the specifically identified DEGs were involved in the ribosome synthesis and the metabolic pathway of photosynthesis, starch, and sucrose metabolism. The DEGs that are activated and respond quickly, as seen during recovery in the tolerant rice line, may play essential roles in regulating subsequent growth and development. This study uncovered the molecular genetic pathways of drought tolerance and extended our understanding of the drought tolerance mechanisms and subsequent recovery regulation in rice.

Comprehensive genomic analysis and expression profiling of the cytochrome P450 genes during abiotic stress and flavonoid biosynthesis in potato (Solanum tuberosum)

The research focused on the cytochrome P450 (CYP) superfamily, a prominent enzyme family involved in plant metabolism. A total of 253 StCYP genes from the potato genome were investigated and characterized through various methods, including phylogentic analysis, physical and chemical characterization, chromosome localization, gene structure and conserved protein domain classification, gene duplication occurrences, collinearity and expression pattern analysis. The 253 StCYPs were classified into seven clans and 33 families, distributed unevenly across 12 chromosomes. Collinearity analysis revealed 28 pairs of orthologous genes between potato StCYPs and Arabidopsis AtCYPs. Moreover, the expression of the StCYPs in various tissue parts of doubled haploid (DM) potatoes under abiotic stress and exogenous hormone treatment was investigated by using RNA-seq data from the PGSC database. It was discovered that one StCYP gene likely contributes to drought stress response through the ABA-dependent pathway. Furthermore, RNA-seq analysis of pigmented tuber flesh from three potato clones at three developmental stages enabled the identification of StCYPs potentially implicated in the flavonoid biosynthesis in potato tubers. In particular, StCYP705A-like was further validated for its potential role in this process. Employing Gfanno software in conjunction with RNA-seq data, seven StCYP genes (Two StC4H, three StF3′H, one StFNS Ⅱ and one StF3′5′H) were identified as flavonoid biosynthetic pathway genes in potato. Additionally, five StCYPs in CYP 71 clan demonstrated a strong association with flavonoid biosynthesis. These findings lay a groundwork for a more comprehensive understanding of the StCYP gene family and further exploration of the functions of StCYP genes in potato abiotic stress tolerance and flavonoids biosynthesis.

COMPREHENSIVE MOLECULAR PROFILING OF UVEAL MELANOMA EVALUATED WITH GENE EXPRESSION PROFILING, PREFERENTIALLY EXPRESSED ANTIGEN IN MELANOMA EXPRESSION, AND NEXT-GENERATION SEQUENCING.

To determine the association between gene-expression profiling (GEP), next-generation sequencing (NGS), preferentially expressed antigen in melanoma (PRAME) features, and metastatic risk in patients with uveal melanoma (UM). A retrospective analysis of patients with UM treated by brachytherapy or enucleation by a single ocular oncologist was conducted from November 2020 and July 2022. Clinicopathologic features, patient outcomes, GEP classification, NGS, and PRAME results were recorded. Comprehensive GEP, PRAME, and NGS testing was performed on 135 UMs. The presence of eukaryotic translation initiation factor 1A, X-chromosomal and splicing factor 3B subunit 1 mutations was significantly associated with GEP class 1A and GEP class 1B, respectively. The presence of BRCA- associated protein-1 mutation was significantly associated with GEP class 2. The average largest basal diameter for tumors with eukaryotic translation initiation factor 1A, X-chromosomal mutations was significantly smaller than those with splicing factor 3B subunit 1 mutations and BRCA1-associated protein-1 mutations. Class 2 tumors metastasized sooner than GEP class 1 tumors. Tumors with splicing factor 3B subunit 1 and/or BRCA1-associated protein-1 mutations metastasized sooner compared with tumors that had either no driver mutation or no mutations at all. Tumors with splicing factor 3B subunit 1 did not have a significantly different time to metastasis compared with tumors with BRCA1-associated protein-1 (P value = 0.97). Forty tumors (30%) were PRAME positive, and the remaining 95 tumors (70%) were PRAME negative. Tumors with PRAME-positive status did not have a significantly different time to metastasis compared with tumors without PRAME-positive status (P value = 0.11). GEP, NGS, and PRAME expression analysis help determine different levels of metastatic risk in UM. Although other prognostic tests exist, the following study reports on the use of NGS for metastatic prognostication in UM. However, limitations of NGS exist, especially with small lesions that are technically difficult to biopsy.

Heterogeneity of hepatocellular carcinoma that responds differently to combination therapy with TACE and Sorafenib as determined by digital spatial gene expression profiling.

The combination of Sorafenib and transcatheter arterial chemoembolization (TACE) exhibits limited efficacy in the treatment of certain advanced hepatocellular carcinomas (HCC), and the molecular mechanisms underlying resistance to this combination remain unclear. This study aims to underscore the distinctive contribution of GeoMx DSP technology in elucidating the molecular intricacies of HCC resistance to the Sorafenib and TACE combination. Patients with advanced HCC during the waiting period before liver transplantation were classified into sensitive and resistant groups based on their response to Sorafenib and TACE combination therapy. Employing GeoMx DSP technology for comprehensive gene expression profiling, we identified pivotal molecular targets linked to resistance against combination therapy. The investigation scrutinized intra-tumoral and inter-individual variances, unveiling a spectrum of crucial molecular targets, such as PLG, PLVAP, immunoglobulin genes, ORM1, and NR4A1, among others. Additionally, we explored signaling pathways associated with treatment responsiveness, including the PPAR signaling pathway. Notably, we emphasized the significance of the immune microenvironment characterized by heightened SPP1 expression in HCC resistance to combination therapy. In the resistant group, SPP1+ tumor-associated macrophage (TAM) infiltration was notably pronounced (p = 0.037), while T-cell depletion showed a mitigated presence (p = 0.013). The study reveals intra- and inter-individual heterogeneity in HCC that is differentially responsive to the combination of Sorafenib and TACE, highlighting multiple key molecular targets associated with treatment resistance. The immune microenvironment is important, and in particular, SPP1+ TAM infiltration may play a key role. Meanwhile, the introduction of immunotherapy in patients resistant to combination therapy may lead to positive results.

A versatile tissue-rolling technique for spatial-omics analyses of the entire murine gastrointestinal tract.

Tissues are dynamic and complex biological systems composed of specialized cell types that interact with each other for proper biological function. To comprehensively characterize and understand the cell circuitry underlying biological processes within tissues, it is crucial to preserve their spatial information. Here we report a simple mounting technique to maximize the area of the tissue to be analyzed, encompassing the whole length of the murine gastrointestinal (GI) tract, from mouth to rectum. Using this method, analysis of the whole murine GI tract can be performed in a single slide not only by means of histological staining, immunohistochemistry and in situ hybridization but also by multiplexed antibody staining and spatial transcriptomic approaches. We demonstrate the utility of our method in generating a comprehensive gene and protein expression profile of the whole GI tract by combining the versatile tissue-rolling technique with a cutting-edge transcriptomics method (Visium) and two cutting-edge proteomics methods (ChipCytometry and CODEX-PhenoCycler) in a systematic and easy-to-follow step-by-step procedure. The entire process, including tissue rolling, processing and sectioning, can be achieved within 2-3 d for all three methods. For Visium spatial transcriptomics, an additional 2 d are needed, whereas for spatial proteomics assays (ChipCytometry and CODEX-PhenoCycler), another 3-4 d might be considered. The whole process can be accomplished by researchers with skills in performing murine surgery, and standard histological and molecular biology methods.

Assessment of long-term stored specimens in the Siriraj Hospital colorectal cancer biobank for RNA sequencing and profiling

Abstract Objectives Biobanks play an important role in advancing cancer research, yet concerns persist regarding the molecular integrity of long-term stored samples. This study assessed fresh frozen (FF) tissues and formalin-fixed paraffin-embedded (FFPE) tissues from the Siriraj Hospital colorectal cancer (CRC) biobank collected during two distinct periods (2011–2012 and 2020–2021). Methods In 2022, FF and FFPE primary cancer tissues from 75 CRC patients were evaluated. RNA sequencing (RNA-Seq) analyzed comprehensive gene expression profiles in FF tissues preserved at −80 °C, while nCounter profiling elucidated cancer-specific RNA transcripts in FFPE tissues stored at ambient temperature. Comparative analyses were conducted between specimens from 2011 to 2012 and 2020–2021. Results The FF tissues stored for approximately 10.5 years were well-suited for RNA-Seq compared to the intact tissues preserved for 1.5 years. Despite consistencies in RNA quantity, RNA integrity, amount of sequencing reads, and CRC gene signature, gene enrichment analysis revealed the decreased ribosome biogenesis, spliceosome and antifolate resistance pathways in the 2011–2012 group. Moreover, the FFPE tissues also showed no alteration in RNA quantity between the two periods, and the nCounter profiling demonstrated comparable CRC-specific gene counts in spite of the significant reduction of raw counts in the 2011–2012 group. Conclusions We report that FF tissues from CRC patients, stored for 10 years, are viable for whole transcriptome RNA-Seq, despite altered pathways such as ribosome biogenesis, spliceosome, and antifolate resistance. Moreover, 10-year-stored FFPE CRC tissues remain suitable for specific RNA profiling using the nCounter pan-cancer panel, despite a significant reduction in raw counts. These findings underscore the enduring contribution of biobanks to molecular research, highlighting their value a decade post-collection.

Cryptic Resilience: Decoding Molecular Networks in Pearl Millet for Enhanced Heat Stress

Pearl millet (<em>Pennisetum glaucum</em>), a vital cereal crop renowned for its drought tolerance, is a cornerstone for smallholder farmers in arid and semi-arid regions, ranking as the fifth most significant cereal globally. Despite its resilience, the molecular mechanisms underlying its tolerance to heat stress remained elusive. To address this knowledge gap, we subjected ten-day-old pearl millet seedlings to an unprecedented temperature of 50°C for 60 seconds. Subsequent next-generation RNA sequencing aimed to unravel differential gene expression in heat-stressed seedlings compared to control conditions. Our analysis revealed a remarkable 29.8% differential expression in the genome sequence in response to heat stress. Heat-stressed pearl millet leaves exhibited differential expression in 11,483 genes, with fold changes ranging from 2 to 18.6 compared to the control group. Of these, 3,612 genes displayed upregulation, while 7,871 genes exhibited downregulation. These genes play roles in diverse biological processes involving crucial enzymes such as aminoacyl-tRNA synthetases, ligases, methyltransferases, oxidoreductases, and DNA-directed RNA polymerases. The Photosystem II Type I Chlorophyll-a/b-binding protein and heat shock proteins displayed the most significant fold changes in heat-stressed leaves. Moreover, various transcription factor families, including bHLH, ERF, NAC, WRKY, MYB-related, C2H2, bZIP, MYB, FAR1, and B3, vital in controlling pearl millet's response to heat stress, were linked to over 100 differentially expressed genes. The dataset generated through this research, shedding light on the molecular processes enabling pearl millet to withstand heat, holds immense value given the crop's role in food security and resilience to extreme weather. In the context of climate change and global warming, this knowledge lays the foundation for further studies on metabolic engineering and selecting crops resilient to high temperatures. Our transcriptomics approach provides comprehensive gene expression profiles of heat-stressed plants. It elucidates pearl millet's response to heat stress, offering a crucial resource for future investigations into crop adaptation strategies.

Donor regulatory T cells rapidly adapt to recipient tissues to control murine acute graft-versus-host disease

The adoptive transfer of regulatory T cells is a promising strategy to prevent graft-versus-host disease after allogeneic bone marrow transplantation. Here, we use a major histocompatibility complex-mismatched mouse model to follow the fate of in vitro expanded donor regulatory T cells upon migration to target organs. Employing comprehensive gene expression and repertoire profiling, we show that they retain their suppressive function and plasticity after transfer. Upon entering non-lymphoid tissues, donor regulatory T cells acquire organ-specific gene expression profiles resembling tissue-resident cells and activate hallmark suppressive and cytotoxic pathways, most evidently in the colon, when co-transplanted with graft-versus-host disease-inducing conventional T cells. Dominant T cell receptor clonotypes overlap between organs and across recipients and their relative abundance correlates with protection efficacy. Thus, this study reveals donor regulatory T cell selection and adaptation mechanisms in target organs and highlights protective features of Treg to guide the development of improved graft-versus-host disease prevention strategies.

Decreased histone expression in chronic rhinosinusitis with nasal polyps.

Histones have been associated with human diseases. However, the implication of extranuclear histone proteins and their potential mechanism in the pathophysiology of chronic rhinosinusitis (CRS) have not been thoroughly investigated. This study was designed to evaluate the role of histones in patients with CRS by comparing histone expression between patients and controls. Nasal polyp (NP) tissues were obtained, and their comprehensive gene expression profiles were investigated by microarray analysis. Differences in expression were verified by reverse transcriptase polymerase chain reaction and immunohistochemical staining. Cell culture and flow cytometry were used to evaluate the role of histones in the pathogenesis of polyps. Significant differences in the microarray analysis were observed between the patient and control groups (P < 0.01). It was found by flow cytometry that the histone (H2BK) can promote cell apoptosis in NPs. Our results indicate that reduced expression of H2BK may contribute to the imbalance process of cell proliferation and apoptosis in CRS with NP.

Hippocampal Lactate-Infusion Enhances Spatial Memory Correlated with Monocarboxylate Transporter 2 and Lactylation.

Lactate has emerged as a key player in regulating neural functions and cognitive processes. Beyond its function as an energy substrate and signal molecule, recent research has revealed lactate to serve as an epigenetic regulator in the brain. However, the molecular mechanisms by which lactate regulates spatial memory and its role in the prevention of cognitive disorders remain unclear. Herein, we injected L-lactate (10 μmol/kg/d for 6 d) into the mouse's hippocampus, followed by the Morris water maze (MWM) test and molecular analyses. Improved spatial memory performances were observed in mice injected with lactate. Besides, lactate upregulated the expression of synaptic proteins post-synaptic density 95 (PSD95), synaptophysin (SYP), and growth associated protein 43 (GAP43) in hippocampal tissues and HT22 cells, suggesting a potential role in synaptic transmission and memory formation. The facilitative role of monocarboxylate transporter 2 (MCT2), a neuron-specific lactate transporter, in this process was confirmed, as MCT2 antagonists attenuated the lactate-induced upregulation of synaptic proteins. Moreover, lactate induced protein lactylation, a post-translational modification, which could be suppressed by MCT2 inhibition. RNA sequencing of lactated-injected hippocampal tissues revealed a comprehensive gene expression profile influenced by lactate, with significant changes in genes associated with transcriptional progress. These data demonstrate that hippocampal lactate injection enhances spatial memory in mice, potentially through the upregulation of synaptic proteins and induction of protein lactylation, with MCT2 playing a crucial role in these processes. Our findings shed light on the multi-faceted role of lactate in neural function and memory regulation, opening new avenues for therapeutic interventions targeting cognitive disorders.

Abstract 7501: Gene expression profiling of rare cells captured from liquid biopsy using the genesis cell isolation system

Abstract Background: Targeting rare cell types such as circulating tumor cells (CTCs), considered to be metastatic precursors in cancer progression, may provide long-term clinical benefits by enhancing patient outcomes. The study of CTCs comes with technical challenges due to their heterogeneity and low cell numbers, leading to difficulties in genomic characterization. This study aims to overcome these technical challenges by developing a comprehensive gene expression profiling workflow using qPCR and RNA sequencing (RNA-Seq) on rare cells enriched with Genesis System with Celselect SlidesTM. Methods: To mimic CTCs in blood, we created a rare cell model sample by spiking A549 non-small cell lung cancer cells at concentrations of 50, 100, 500 and 1000 cells/ml in whole blood from healthy donors. The Genesis System, which can capture rare cells of 8µm-30µm, isolated 83.73% of spiked A549 cells in whole blood. Using the same blood samples without A549 spiked in, we enriched cells using the Genesis and it was used as a baseline for gene expression controls. High quality RNA was extracted from each of the enriched samples and used for both qPCR and RNA-Seq to detect the gene expression signature of the non-small cell lung cancer cells. Results: Our analyses revealed significant differential expression of cancer-related genes (p &amp;lt; 0.05) in all A549-spiked samples when compared to the blood-only controls. Notably, in the 50 cells/ml dilution, RNA-Seq analysis identified over 3,000 differentially expressed genes, encompassing protein-coding genes, long non-coding RNAs, and small non-coding RNAs. Among these, 759 genes were consistently present across all enriched samples, suggesting a common expression pattern. To investigate the potential utility of these genes as non-small cell lung cancer biomarkers, we constructed a custom qPCR array comprising 38 of these genes and pre-amplified their targets using 50pg of RNA from the enriched cell samples. Notably, six genes from this panel (MET, TOP2A, NF1, SPP1, GAPDH, and ANXA5) exhibited significant differential expression (+/- 4-fold, p&amp;lt;0.05) in the enriched samples. MET and TOP2A, in particular, are well-known biomarkers for non-small cell lung cancer. Conclusion: Our liquid biopsy workflow demonstrates the recovery of high-quality RNA from enriched rare cells, including CTCs. It enables comprehensive profiling of the tumor transcriptome, encompassing RNAs of various sizes, including miRNAs. Our approach has the potential to facilitate the identification of patient-specific biomarkers, enabling swift monitoring using preamplification and qPCR in advancement of targeted oncology therapy and research. Citation Format: Srikanth Perike, Angelica Olcott, Cissy Jiang, Nish Kumar, Nathan Knapp, Jennifer Placek, Candice Cox, Yoon-Tae Kang, Linda Lingelbach, Elizabeth Dreskin. Gene expression profiling of rare cells captured from liquid biopsy using the genesis cell isolation system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7501.