Transmembrane Receptor Signaling Research Articles

Galectin-3 disrupts tight junctions of airway epithelial cell monolayers by inducing expression and release of matrix metalloproteinases upon influenza a infection.

Galectins are β-galactosyl-binding lectins with key roles in early development, immune regulation, and infectious disease. Influenza A virus (IAV) infects the airway epithelia, and in severe cases may lead to bacterial superinfections and hypercytokinemia, and eventually, to acute respiratory distress syndrome (ARDS) through the breakdown of airway barriers. The detailed mechanisms involved, however, remain poorly understood. Our prior in vivo studies in a murine model system revealed that upon experimental IAV and pneumococcal primary and secondary challenges, respectively, galectin-1 and galectin-3 (Gal-3) are released into the airway and bind to the epithelium that has been desialylated by the viral neuraminidase, contributing to secondary bacterial infection and hypercytokinemia leading to the clinical decline and death of the animals. Here we report the results of in vitro studies that reveal the role of the extracellular Gal-3 in additional detrimental effects on the host by disrupting the integrity of the airway epithelial barrier. IAV infection of the human airway epithelia cell line A549 increased release of Gal-3 and its binding to the A549 desialylated cell surface, notably to the transmembrane signaling receptors CD147 and integrin-β1. Addition of recombinant Gal-3 to A549 monolayers resulted in enhanced expression and release of matrix metalloproteinases, leading to disruption of cell-cell tight junctions, and a significant increase in paracellular permeability. This study reveals a critical mechanism involving Gal-3 that may significantly contribute to the severity of IAV infections by promoting disruption of tight junctions and enhanced permeability of the airway epithelia, potentially leading to lung edema and ARDS.

Integrative Network Pharmacology Unveils Limonia acidissima as a Potential Natural Product for Targeting Cancer

Cancer remains a formidable health challenge worldwide, with complex molecular mechanisms driving its initiation, progression, and therapeutic resistance. In this study, we employed bioinformatics analyses to elucidate the molecular underpinnings of cancer biology, focusing on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Our GO analysis revealed the enrichment of key biological processes such as protein phosphorylation, regulation of programmed cell death, and transmembrane receptor signaling pathways, underscoring the critical roles of signaling cascades and regulatory mechanisms in tumorigenesis. Similarly, molecular functions such as protein kinase activity and ATP binding were identified as significantly enriched, highlighting the importance of protein kinases and molecular interactions in cancer development and progression. The KEGG pathway analysis further delineated dysregulated signaling pathways associated with cancer, including the MAPK and PI3K-Akt signaling pathways, implicating these pathways as central regulators of cancer progression. These findings deepen our understanding of cancer biology and offer potential targets for therapeutic intervention. Integrating multi-omics data and systems biology approaches may provide deeper insights into the intricate networks underlying cancer pathogenesis, paving the way for developing more effective treatments for cancer patients.

Targeted therapy for capillary-venous malformations

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIK3CA or TEK, an endothelial transmembrane receptor signaling through PIK3CA. Venous malformations are associated with pain, bleedings, thrombosis, pulmonary embolism, esthetic deformities and, in severe cases, life-threatening situations. No authorized medical treatment exists for patients with venous malformations. Here, we created a genetic mouse model of PIK3CA-related capillary venous malformations that replicates patient phenotypes. We showed that these malformations only partially signal through AKT proteins. We compared the efficacy of different drugs, including rapamycin, a mTORC1 inhibitor, miransertib, an AKT inhibitor and alpelisib, a PI3Kα inhibitor at improving the lesions seen in the mouse model. We demonstrated the effectiveness of alpelisib in preventing vascular malformations’ occurrence, improving the already established ones, and prolonging survival. Considering these findings, we were authorized to treat 25 patients with alpelisib, including 7 children displaying PIK3CA (n = 16) or TEK (n = 9)-related capillary venous malformations resistant to usual therapies including sirolimus, debulking surgical procedures or percutaneous sclerotherapies. We assessed the volume of vascular malformations using magnetic resonance imaging (MRI) for each patient. Alpelisib demonstrated improvement in all 25 patients. Vascular malformations previously considered intractable were reduced and clinical symptoms were attenuated. MRI showed a decrease of 33.4% and 27.8% in the median volume of PIK3CA and TEK malformations respectively, over 6 months on alpelisib. In conclusion, this study supports PI3Kα inhibition as a promising therapeutic strategy in patients with PIK3CA or TEK-related capillary venous malformations.

Decoding the thermodynamic details of transmembrane receptor signaling fidelity: An in silico approach

Decoding the thermodynamic details of transmembrane receptor signaling fidelity: An in silico approach

Seascapes Shaped the Local Adaptation and Population Structure of South China Coast Yellowfin Seabream (Acanthopagrus latus).

Understanding the genetic composition and regional adaptation of marine species under environmental heterogeneity and fishing pressure is crucial for responsible management. In order to understand the genetic diversity and adaptability of yellowfin seabream (Acanthopagrus latus) along southern China coast, this study was conducted a seascape genome analysis on yellowfin seabream from the ecologically diverse coast, spanning over 1600 km. A total of 92 yellowfin seabream individuals from 15 sites were performed whole-genome resequencing, and 4,383,564 high-quality single nucleotide polymorphisms (SNPs) were called. By conducting a genotype-environment association analysis, 29,951 adaptive and 4,328,299 neutral SNPs were identified. The yellowfin seabream exhibited two distinct population structures, despite high gene flow between sites. The seascape genome analysis revealed that genetic structure was influenced by a variety of factors including salinity gradients, habitat distance, and ocean currents. The frequency of allelic variation at the candidate loci changed with the salinity gradient. Annotation of these loci revealed that most of the genes are associated with osmoregulation, such as kcnab2a, kcnk5a, and slc47a1. These genes are significantly enriched in pathways associated with ion transport including G protein-coupled receptor activity, transmembrane signaling receptor activity, and transporter activity. Overall, our findings provide insights into how seascape heterogeneity affects adaptive evolution, while providing important information for regional management in yellowfin seabream populations.

Integrated RNA-sequencing and network analysis approach to identify the Hub genes and vital pathways associated with gastric cancer

Context: Gastric cancer is one of the most prevalent types of cancer in developing countries and ranks fourth in terms of death causes. Helicobacter pylori infection is a significant contributor to the emergence of gastric cancer. Lack of early diagnosis of gastric cancer is a leading cause of death. Aims: To identify the key genes and pathways involved in gastric cancer. Methods: This study performed a comprehensive analysis of RNA-Seq data from human gastric cancer and adjacent normal tissues. Raw data passed quality checks with FastQC and were aligned to GRCh38 using HISAT2. Subread's FeatureCounts handled transcript assembly and quantification. DESeq2 pinpointed significant genes, while ClueGO explored gene ontology and KEGG pathways. Protein-protein interaction networks, constructed with StringApp, aided in identifying hub genes through CytoHubba. This holistic approach yields insights into the molecular mechanisms underpinning gastric cancer. Results: This study detected 711 differentially expressed genes (DEGs) between normal and gastric samples. A total of 594 genes were identified as upregulated and 117 as downregulated. Major DEGs are enriched in signal transduction, stimulus-response regulation, transmembrane signaling receptor activity, and signal transduction pathways involving cytokines. In addition, 20 hub genes from the PPI network were identified based on MCC rank analysis from the CytoHubba plugin, contributing to the progression of gastric cancer. Conclusions: The top six hub genes, CD4, CTLA4, CD28, CD80, CD27, and SELL, are expected to regulate several pathways and may serve as potential biomarkers for the early detection and treatment of gastric cancer patients.

Autoinducer-2 quorum sensing regulates biofilm formation and chain elongation metabolic pathways to enhance caproate synthesis in microbial electrochemical system

Quorum sensing (QS) have been explored extensively. However, most studies focused on N-acyl homoserine lactones (AHLs) participating in intraspecies QS. In this study, autoinducer-2 (AI-2, participating in interspecies QS) with different concentration was investigated for chain elongation in microbial electrosynthesis (MES). The results demonstrated that the R3 treatment, which involved adding 10 μM of 4,5-dihydroxy-2,3-pentanedione (DPD) in the reactor, exhibited the best performance. The concentration of caproate was increased by 66.88% and the redox activity of cathodic electroactive biofilms (EABs) was enhanced. Meanwhile, microbial community data indicated that Negativicutes relative abundance was increased obviously in R3 treatment. In this study, the transcriptome Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases were used to analyze the metabolic pathway of chain elongation involving fatty acid biosynthesis (FAB) pathway and reverse β-oxidization (RBO) pathway. KEGG analysis revealed that fatty acid elongation metabolism (p < 0.001), tryptophan metabolism (p < 0.01), arginine and proline metabolism (p < 0.05) were significantly improved in R3 treatment. GO analysis suggested that R3 treatment mainly upregulated significantly transmembrane signaling receptor activity (p < 0.01), oxidoreductase activity (p < 0.05), and phosphorelay signal transduction (p < 0.05). Moreover, metatranscriptomic analyses also showed that R3 treatment could upregulate the LuxP extracellular receptor, LuxO transcriptional activator, LsrB periplasmic protein, and were beneficial to both FAB and RBO pathways. These findings provided a new insight into chain elongation in MES system.

Understanding key genetic make-up of different coat colour in Bayinbuluke sheep through a comparative transcriptome profiling analysis

Coat color is a distinctive feature of mammals, especially in distinguishing animal breeds, and the diversity of animal coat color provides an important model phenotype for exploring gene roles and studying gene mutations. Selective breeding programs can be used to enhance or modify certain physical traits in Bayinbuluke sheep, including their coat color. To elaborately understand the differential expression of coat tissue of Bayinbuluke sheep with respect to coat colour and genetic make ups, the molecular mechanism of the difference in coat color phenotype of the sheep's head and neck was explored through RT-PCR assay based transcriptomic analysis. In this study, sixteen samples of coat tissues of 8 individuals Bayinbuluke sheep with different hair colors were collected for transcriptome sequencing analysis, and the differential expression genes of MEwhite module in BL vs BR group and WGCNA were analyzed by gene ontology and Kyoto Gene Encyclopedia enrichment, and the results were significantly enriched in G protein-coupled receptor, transmembrane signaling receptor activity, tyrosine metabolism, melanin production and other metabolic pathways. The identified DCT, ASIP, GPR143, PMEL, TYRP1 and MC1R genes Bayinbuluke sheep coat have all been linked with important roles in the regulation of melanin synthesis as immune stability. Therefore, understanding the genetic and molecular basis of these pathways can help in developing novel approaches in sheep coat colour as well as improved sheep immunity.

14-3-3zeta Regulates Transmembrane Receptor Signaling by Binding TRAF Proteins

Abstract Adaptor proteins are critical for signal transduction events involving cytokine signaling, host-response, and autoimmune diseases. Our laboratory is interested in understanding the immune regulatory role of 14-3-3zeta (z), an adaptor protein, in signal transductions and diseases. We examined the role of 14-3-3z in interleukin-17 (IL-17A) signaling and autoimmune inflammatory arthritis using genetically modified cells and rats. The IL-17A signal transduction requires IL-17 receptor cytoplasmic domain interactions with Act1 and several TRAF proteins. Our results show that 14-3-3z interacts with TRAF6, TRAF2, and TRAF5 upon IL-17A stimulation which has functional consequences. The interaction of 14-3-3z and TRAF protein was found to be specific, as mutation of the interacting residues resulted in the loss of binding with functional impacts. Further interaction studies show a higher affinity of 14-3-3z for TRAF6, which has two putative 14-3-3 binding sites. To examine the generality of 14-3-3z-TRAF interactions and their role in another transmembrane receptor signaling, we examined RANKL signal transduction. Similar to IL-17A, 14-3-3z-TRAF interaction was increased upon RANKL treatment and had functional consequences. While there are common domains and significant sequence conservation between the TRAF proteins, a specificity of interactions exists with 14-3-3z. Our results show that the 14-3-3z-TRAF axis is a novel regulatory mechanism underneath several transmembrane receptor-mediated signaling. Current studies target understanding the molecular basis of interactions between 14-3-3z and specific TRAF proteins.

Integrative Ligand-Based Pharmacophore Modeling, Virtual Screening, and Molecular Docking Simulation Approaches Identified Potential Lead Compounds against Pancreatic Cancer by Targeting FAK1

Pancreatic cancer is a very deadly disease with a 5-year survival rate, making it one of the leading causes of cancer-related deaths globally. Focal adhesion kinase 1 (FAK1) is a ubiquitously expressed protein in pancreatic cancer. FAK, a tyrosine kinase that is overexpressed in cancer cells, is crucial for the development of tumors into malignant phenotypes. FAK functions in response to extracellular signals by triggering transmembrane receptor signaling, which enhances focal adhesion turnover, cell adhesion, cell migration, and gene expression. The ligand-based drug design approach was used to identify potential compounds against the target protein, which included molecular docking: ADME (absorption, distribution, metabolism, and excretion), toxicity, molecular dynamics (MD) simulation, and molecular mechanics generalized born surface area (MM-GBSA). Following the retrieval of twenty hits, four compounds were selected for further evaluation based on a molecular docking approach. Three newly discovered compounds, including PubChem CID24601203, CID1893370, and CID16355541, with binding scores of -10.4, -10.1, and -9.7 kcal/mol, respectively, may serve as lead compounds for the treatment of pancreatic cancer associated with FAK1. The ADME (absorption, distribution, metabolism, and excretion) and toxicity analyses demonstrated that the compounds were effective and nontoxic. However, further wet laboratory investigations are required to evaluate the activity of the drugs against the cancer.

AML-060 A Truncated Nucleus Isoform of FGFR1 Drives the Transformation of Leukemia Stem Cells in Leukemogenesis

Myeloid and lymphoid malignancies associated with chimeric FGFR1 kinases are the hallmark of stem cell leukemia and lymphoma syndrome (SCLL). In all cases, FGFR1 kinase is constitutively phosphoactivated in the cytoplasm as a result of chromosome translocations. Recently, we demonstrated that these chimeric kinases could be cleaved by granzyme B to generate a truncated derivative, tnFGFR1, which localized exclusively into the nucleus and was not phosphorylated. In this study, we used the mouse bone marrow transduction and transplantation model to demonstrate the leukemic transformation ability of this tnFGFR1 and identified its critical downstream targets, FLT3 and KIT, in mouse and acute myeloid leukemia (AML) patient samples. Stem cell transduction and transplantation in syngeneic mice was used to assess the transforming ability of tnFGFR1 in bone marrow stem cells, and RPPA and RNA-Seq were used to examine the related signaling pathways and regulated target genes. We now show that tnFGFR1 can independently lead to oncogenic transformation of hematopoietic stem cells. These leukemia cells show a mixed immunophenotype with a B-cell B220+Igm- profile in the majority of cells and Kit+ in virtually all cells, suggesting a stem cell disease. tnFGFR1 induces a distinct profile of altered gene expression with significant upregulation of transmembrane signaling receptors including FLT3 and KIT. De novo human AML also expresses tnFGFR1, which correlates with upregulation of FLT3 and KIT as in mouse leukemia cells. ChIP analysis demonstrates tnFGFR1 occupancy at the Flt3 and Kit promoters, suggesting a direct transcriptional regulation. Cells transformed with tnFGFR1 are insensitive to FGFR1 inhibitors but sensitive to the FLT3 inhibitor quizartinib (AC220), suggesting an alternative approach for the treatment of SCLL. This study demonstrates a novel model for the transformation of hematopoietic stem cells by chimeric FGFR1 kinases with the combined effects of direct protein activation by the full-length kinases and transcriptional regulation by tnFGFR1. In human AML, tnFGFR1 activation leads to increased FLT3 and KIT expression, and higher FLT3 and GZMB expression levels are associated with inferior prognosis. These observations provide insights into the relative therapeutic value of targeting FGFR1 and FLT3 in treating AML with this characteristic gene expression profile.

Novel Application of Infrared Radiation Therapy: Spirit Identity Powder-Generated Far Infrared Radiation Inhibits the Proliferation of Human Male Liver Cancer Cells by Activating the Transmembrane Attack Complex

Far infrared radiation (FIR) has been primarily used as a therapeutic modality for its inhibitory effect on the proliferation of cancer cells. Previous studies have focused on the inhibitory effects of FIR on mitochondrial metabolism, neglecting its effect on cancer cell membranes. In this study, we investigated the biological inhibitory effect of FIR on the membrane of liver cancer cells. We fabricated an FIR radiator (power density of 37.2 mW/cm2, emissivity of 92.3%) using spirit identity (SI) powder and irradiated liver cancer cells for 3 h for 3 days, resulting in decreased cell viability and ATP production in irradiated cells. To corroborate the mechanism underlying the inhibitory effect on the cell membrane, we performed transcriptional analyses of mRNA and protein expression. Transcriptional analysis showed activation of transmembrane signaling receptors in the gene ontology and systemic lupus erythematosus in the KEGG pathway. The mRNA results showed significantly high expression of membrane attack complex (MAC), and protein analysis results showed a higher expression of proteins C7 and C8β than C5 and C6. Thus, SI powder-generated FIR can inhibit the proliferation of liver cancer cells by activating the MAC in the cell membrane.

Transcriptome Analysis Reveals Contrasting Plant Responses of Sorghum bicolor upon Colonization by Two Formae Speciales of Sporisorium reilianum

The biotrophic fungus Sporisorium reilianum exists in two host-adapted formae speciales that cause head smut in maize (S. reilianum f. sp. zeae; SRZ) and sorghum (S. reilianum f. sp. reilianum; SRS). In sorghum, the spread of SRZ is limited to the leaves. To understand the plant responses to each forma specialis, we determined the transcriptome of sorghum leaves inoculated either with SRS or SRZ. Fungal inoculation led to gene expression rather than suppression in sorghum. SRZ induced a much greater number of genes than SRS. Each forma specialis induced a distinct set of plant genes. The SRZ-induced genes were involved in plant defense mainly at the plasma membrane and were associated with the Molecular Function Gene Ontology terms chitin binding, abscisic acid binding, protein phosphatase inhibitor activity, terpene synthase activity, chitinase activity, transmembrane transporter activity and signaling receptor activity. Specifically, we found an upregulation of the genes involved in phospholipid degradation and sphingolipid biosynthesis, suggesting that the lipid content of the plant plasma membrane may contribute to preventing the systemic spread of SRZ. In contrast, the colonization of sorghum with SRS increased the expression of the genes involved in the detoxification of cellular oxidants and in the unfolded protein response at the endoplasmic reticulum, as well as of the genes modifying the cuticle wax and lipid composition through the generation of alkanes and phytosterols. These results identified plant compartments that may have a function in resistance against SRZ (plasma membrane) and susceptibility towards SRS (endoplasmic reticulum) that need more attention in the future.

A truncated derivative of FGFR1 kinase cooperates with FLT3 and KIT to transform hematopoietic stem cells in syndromic and de novo AML

BackgroundMyeloid and lymphoid malignancies associated with chimeric FGFR1 kinases are the hallmark of stem cell leukemia and lymphoma syndrome (SCLL). In all cases, FGFR1 kinase is constitutively phosphoactivated as a result of chromosome translocations, which lead to acquisition of dimerization motifs in the chimeric proteins. Recently, we demonstrated that these chimeric kinases could be cleaved by granzyme B to generate a truncated derivative, tnFGFR1, which localized exclusively into the nucleus and was not phosphorylated.MethodsStem cell transduction and transplantation in syngeneic mice was used to assess the transforming ability of tnFGFR1 in bone marrow stem cells, and RPPA and RNA-Seq was used to examine the related signaling pathways and regulated target genes.ResultsFor the first time, we show that this non-classical truncated form of FGFR1 can independently lead to oncogenic transformation of hematopoietic stem cells in an animal model in vivo. These leukemia cells show a mixed immunophenotype with a B-cell B220 + Igm- profile in the majority of cells and Kit+ in virtually all cells, suggesting a stem cell disease. tnFGFR1, however, does not activate classic FGFR1 downstream signaling pathways but induces a distinct profile of altered gene expression with significant upregulation of transmembrane signaling receptors including FLT3 and KIT. We further show that de novo human AML also express tnFGFR1 which correlates with upregulation of FLT3 and KIT as in mouse leukemia cells. ChIP analysis demonstrates tnFGFR1 occupancy at the Flt3 and Kit promoters, suggesting a direct transcriptional regulation. Cells transformed with tnFGFR1 are insensitive to FGFR1 inhibitors but treatment of these cells with the Quizartinib (AC220) FLT3 inhibitor, suppresses in vitro growth and development of leukemia in vivo. Combined treatment with FGFR1 and FLT3 inhibitors provides increased survival compared to FGFR1 inhibition alone.ConclusionsThis study demonstrates a novel model for transformation of hematopoietic stem cells by chimeric FGFR1 kinases with the combined effects of direct protein activation by the full-length kinases and transcriptional regulation by the truncated nuclear tnFGFR1 derivative, which is associated with GZMB expression levels. Genes significantly upregulated by tnFGFR1 include Flt3 and Kit which promote a leukemia stem cell phenotype. In human AML, tnFGFR1 activation leads to increased FLT3 and KIT expression, and higher FLT3 and GZMB expression levels are associated with an inferior prognosis. These observations provide insights into the relative therapeutic value of targeting FGFR1 and FLT3 in treating AML with this characteristic gene expression profile.

NFAT1 Orchestrates Spinal Microglial Transcription and Promotes Microglial Proliferation via c-MYC Contributing to Nerve Injury-Induced Neuropathic Pain.

Peripheral nerve injury‐induced spinal microglial proliferation plays a pivotal role in neuropathic pain. So far, key intracellular druggable molecules involved in this process are not identified. The nuclear factor of activated T‐cells (NFAT1) is a master regulator of immune cell proliferation. Whether and how NFAT1 modulates spinal microglial proliferation during neuropathic pain remain unknown. Here it is reported that NFAT1 is persistently upregulated in microglia after spinal nerve ligation (SNL), which is regulated by TET2‐mediated DNA demethylation. Global or microglia‐specific deletion of Nfat1 attenuates SNL‐induced pain and decreases excitatory synaptic transmission of lamina II neurons. Furthermore, deletion of Nfat1 decreases microglial proliferation and the expression of multiple microglia‐related genes, such as cytokines, transmembrane signaling receptors, and transcription factors. Particularly, SNL increases the binding of NFAT1 with the promoter of Itgam, Tnf, Il‐1b, and c‐Myc in the spinal cord. Microglia‐specific overexpression of c‐MYC induces pain hypersensitivity and microglial proliferation. Finally, inhibiting NFAT1 and c‐MYC by intrathecal injection of inhibitor or siRNA alleviates SNL‐induced neuropathic pain. Collectively, NFAT1 is a hub transcription factor that regulates microglial proliferation via c‐MYC and guides the expression of the activated microglia genome. Thus, NFAT1 may be an effective target for treating neuropathic pain.

Abstract 5837: A truncated nucleus-located derivative of FGFR1 contributes to the transformation of leukemia stem cell in leukemogenesis driven by FGFR1 fusion kinases

Abstract Myeloid and lymphoid malignancies associated with chimeric FGFR1 kinases are the hallmark of stem cell leukemia and lymphoma syndrome (SCLL). In all cases, FGFR1 kinase is constitutively phosphoactivated as a result of chromosome translocations, which lead to acquisition of dimerization motifs in the chimeric proteins. Recently, we demonstrated that these chimeric kinases could be cleaved by granzyme B to generate a truncated derivative, tnFGFR1, which localized exclusively into the nucleus and was not phosphorylated. Stem cell transduction and transplantation in syngeneic mice were used to assess the transforming ability of tnFGFR1 in bone marrow stem cells, and the results showed that tnFGFR1 can independently lead to oncogenic transformation of hematopoietic stem cells. These leukemia cells show a mixed immunophenotype with a B-cell B220+Igm- profile in the majority of cells and Kit+ in virtually all cells, suggesting a stem cell disease. RPPA and RNA-Seq examination of the related signaling pathways and target genes revealed that tnFGFR1, however, does not activate classic FGFR1 downstream signaling pathways but induces a distinct profile of altered gene expression with significant upregulation of transmembrane signaling receptors including FLT3 and KIT. De novo human AML also expressed tnFGFR1 which correlates with upregulation of FLT3 and KIT as in mouse leukemia cells. ChIP analysis demonstrates tnFGFR1 occupancy at the Flt3 and Kit promoters, suggesting a direct transcriptional regulation. Cells transformed with tnFGFR1 are insensitive to FGFR1 inhibitors but treatment of these cells with the Quizartinib (AC220) FLT3 inhibitor, suppresses in vitro growth and development of leukemia in vivo suggesting an alternative approach for treatment of SCLL. This study demonstrates a novel model for transformation of hematopoietic stem cells by chimeric FGFR1 kinases results with the combined effects of direct protein activation by the full-length kinases and gene regulation by the truncated nucleus derivative tnFGFR1, which is associated with GZMB expression levels. Genes significantly upregulated by tnFGFR1 include Flt3 and Kit which promote a leukemia stem cell phenotype. In human AML, tnFGFR1 activation leads to increased FLT3 and KIT expression, and higher FLT3 and GZMB expression levels are associated with inferior prognosis. These observations provide insights into the relative therapeutic value of targeting FGFR1 and FLT3 in treating AML with this characteristic gene expression profile. Citation Format: Baohuan Cai, Yun Liu, Yating Chong, Hualei Zhang, Stephanie Mori, Atsuko Matsunaga, Xuexiu Fang, John Cowell, Tianxiang Hu. A truncated nucleus-located derivative of FGFR1 contributes to the transformation of leukemia stem cell in leukemogenesis driven by FGFR1 fusion kinases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5837.

Integrated Analysis of miRNA-mRNA Expression in Mink Lung Epithelial Cells Infected With Canine Distemper Virus

Canine distemper (CD) caused by canine distemper virus (CDV) is one of the major infectious diseases in minks, bringing serious economic losses to the mink breeding industry. By an integrated analysis of microRNA (miRNA)-messenger RNA (mRNA), the present study analyzed the changes in the mink transcriptome upon CDV infection in mink lung epithelial cells (Mv. l. Lu cells) for the first time. A total of 4,734 differentially expressed mRNAs (2,691 upregulated and 2,043 downregulated) with |log2(FoldChange) |>1 and P-adj<0.05 and 181 differentially expressed miRNAs (152 upregulated and 29 downregulated) with |log2(FoldChange) |>2 and P-adj<0.05 were identified. Gene Ontology (GO) enrichment indicated that differentially expressed genes (DEGs) were associated with various biological processes and molecular function, such as response to stimulus, cell communication, signaling, cytokine activity, transmembrane signaling receptor activity and signaling receptor activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the combination of miRNA and mRNA was done for immune and inflammatory responses, such as Janus kinase (JAK)-signal transducer and activator (STAT) signaling pathway and nuclear factor (NF)-kappa B signaling pathway. The enrichment analysis of target mRNA of differentially expressed miRNA revealed that mir-140-5p and mir-378-12 targeted corresponding genes to regulate NF-kappa B signaling pathway. JAK-STAT signaling pathway could be modulated by mir-425-2, mir-139-4, mir-140-6, mir-145-3, mir-140-5p and mir-204-2. This study compared the influence of miRNA-mRNA expression in Mv. l. Lu cells before and after CDV infection by integrated analysis of miRNA-mRNA and analyzed the complex network interaction between virus and host cells. The results can help understand the molecular mechanism of the natural immune response induced by CDV infection in host cells.

Gene expression of equine cumulus cells during in vitro and in vivo oocyte maturation

In vivo matured oocytes collected from dominant, pre-ovulatory follicles have superior developmental competence when compared to their in vitro matured counterparts, indicating that in vitro maturation (IVM) methods are sub-optimal. Cumulus cells (CC) have a critical role during oocyte maturation; thus, their gene expression holds key information regarding cellular processes associated with oocyte development. Understanding these biological events occurring during in vivo maturation of equine oocytes has the potential to improve IVM conditions. The aim of this study was to compare gene expression profiles of CC obtained from in vitro matured oocytes (IVM-CC) and in vivo matured oocytes (IVV-CC) by identifying differentially expressed genes (DEG) and significant biological pathways related to maturation. For the IVM-CC group, cumulus-oocyte complexes (COCs; n =12) were collected and matured in vitro as previously described (Meyers et al. Reprod Fertil Dev. 2019; 12:1874-1884). COCs for the IVV-CC group (n = 12) were collected after gonadotropin induction of ovulation as previously described (Foss et al. EVJ. 2013; 45:39-43). Extracted RNA from CC was sequenced, generating an average of 24 million reads/sample. The raw reads were trimmed (Trimmgalore) and mapped (STAR) to the current equine reference genome. Mapped reads were quantified (Featurecount) and compared between IVM-CC and IVV-CC groups,using the DESeq2 package in R software. A total of 14,479 genes were expressed in the cumulus cells. Principal component analysis showed a uniform pattern of gene expression among the IVV-CC, in contrast to a more scattered pattern in IVM-CC samples. We found 6,677 DEGs with 4,490 downregulated and 2,187 upregulated genes in the IVM-CC group. The enrichment pathway analysis demonstrated that downregulated genes were involved in transmembrane signaling receptors and chemical stimulus detection, while upregulated genes were associated with chromosome segregation, DNA repair, sister chromatid segregation, DNA replication, mitotic cell cycle process, and nuclear division. We found abnormal expression of genes involved in cumulus expansion and gonadotropin receptors in the IVM-CC group. Our data highlights that IVM culture conditions seem to be a distant replica of the in vivo conditions, as demonstrated by the divergent gene expression of the cumulus cells. The difference observed in gene expression and associated pathways could explain the variability in developmental competence between the in vivo and in vitro matured gametes. Lastly, this data serves as a starting point to determine modifications of current in vitro maturation culture protocols necessary to mimic in vivo conditions. This study was funded by the Theriogenology Foundation and Center for Equine Health at UC Davis.

Metabolomic and Transcriptomic Responses of Argopecten irradians concentricus to Thermal Stresses

The bay scallop southern subspecies, Argopecten irradians concentricus, which is widely cultured in southern China waters, is a eurythermal animal that is more adaptive to high-temperature waters but less tolerant to low-temperature waters. Despite that temperature is one of the most dominant environmental factors affecting dramatically its growth, survival, and hence production, the mechanism underlying the responses to thermal stress has not been explored in this animal. In this study, transcriptomic and metabolomic analyses were carried out in the adductor muscles of the bay scallop southern subspecies exposed to low and high thermal stresses. Transcriptomic analyses revealed that differentially expressed genes (DEGs) were enriched in the calcium ion, kinase activity, phosphatase activity, and lipid-related pathways in the group exposed to thermal stress, while most DEGs were enriched in the RNA processing pathways in the group exposed to low-temperature thermal stress. A large number of differentially expressed transcription factors involved in oxidation-reduction process, membrane-related pathways, transmembrane signaling receptor activity, and transduction-related pathways were induced by exposure to thermal stress. Results from metabolomic analyses showed that the retinol metabolism, inositol phosphate metabolism, and phosphatidylinositol pathways may be involved in the responses to high thermal stress, while more signaling pathways were enriched in the group exposed to low thermal stress. Integrated analyses of the transcriptomic and metabolomic data indicated that the degradation of valine, leucine, and isoleucine and the tricarboxylic acid cycle may be the major events induced by low and high thermal stress, and the retinol pathway may play critical roles in the responses of the scallops to high thermal stress. It seems that the bay scallop southern species have evolved distinct pathways in dealing with low and high thermal stress. Our results may provide useful information for marker-assisted selection of high-resistant strains in this scallop.

Rora Regulates Neutrophil Migration and Activation in Zebrafish.

Neutrophil migration and activation are essential for defense against pathogens. However, this process may also lead to collateral tissue injury. We used microRNA overexpression as a platform and discovered protein-coding genes that regulate neutrophil migration. Here we show that miR-99 decreased the chemotaxis of zebrafish neutrophils and human neutrophil-like cells. In zebrafish neutrophils, miR-99 directly targets the transcriptional factor RAR-related orphan receptor alpha (roraa). Inhibiting RORα, but not the closely related RORγ, reduced chemotaxis of zebrafish and primary human neutrophils without causing cell death, and increased susceptibility of zebrafish to bacterial infection. Expressing a dominant-negative form of Rorα or disrupting the roraa locus specifically in zebrafish neutrophils reduced cell migration. At the transcriptional level, RORα regulates transmembrane signaling receptor activity and protein phosphorylation pathways. Our results, therefore, reveal previously unknown functions of miR-99 and RORα in regulating neutrophil migration and anti-microbial defense.