DNA-Protein Crosslinking Problem in Saccharomyces cerevisiae for methanol utilization
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ABSTRACT: Formaldehyde-induced DNA-protein crosslinkings (DPCs) and large repeated DNA fragments suggest strategies for methanol detoxification and phenotype enhancement
Project description:Formaldehyde-induced DNA-protein crosslinkings (DPCs) and large repeated DNA fragments suggest strategies for methanol detoxification and phenotype enhancement
Project description:Frameshift insertion/deletions can produce highly immunogenic neoantigens; however, frameshift-derived transcripts are often degraded by the nonsense-mediated mRNA decay (NMD) pathway. Leveraging multiomics and checkpoint in-hibitor (CPI) response data from over 1,000 patients, we demonstrate that reduced expression or genetic loss of the NMD mediator SMG1 correlates with improved CPI responses. SMG1 inhibition ex vivo and in vivo activates and expands tumour-reactive lymphocytes and potentiates CPI responses. Mechanistically, SMG1 inhibi-tion stabilises frameshift-derived transcripts and increases the abundance and sur-face presentation of immunogenic neoantigens, shifting the neoepitope count from a low- to a high-tumour mutational burden (TMB)-like state without causing DNA damage. Co-culture of lymphocytes with tumour cells upon SMG1i induces antigen-dependent T cell activation and tumour cell killing. Our findings highlight SMG1 in-hibition as a promising immuno-oncology strategy to harness an untapped source of immunogenic neoantigens to enhance tumour immunogenicity and improve CPI efficacy, with broad applicability irrespective of TMB status.
Project description:Formaldehyde-induced DNA-protein crosslinkings (DPCs) and large repeated DNA fragments suggest strategies for methanol detoxification and phenotype enhancement
Project description:The SNF1-related protein kinase 2 (SnRK2) pathway is a central regulator of abiotic stress signaling in land plants; however, its evolutionary origins and functional conservation across the green lineage remain poorly understood. Land plants evolved from streptophyte algae, whereas the chlorophyte algae, including the widely studied model Chlamydomonas reinhardtii, represent an older lineage that diverged from streptophytes over one billion years ago. Here, we identify and characterize a functional SnRK2 signaling module in Chlamydomonas reinhardtii. We show that the isoform SnRK2.7 is required for osmotic stress tolerance and general cellular viability, thus offering an alternative model for dissecting SnRK2 functions in algae. SnRK2.7 localizes to the contractile vacuole, an osmoregulatory organelle lost during streptophyte evolution, revealing a lineage-specific functional adaptation. Together with MAPKKK3, a B1/B3-RAF kinase, and the clade A protein phosphatase PP2C3, these components constitute a SnRK2 signaling module in Chlamydomonas reinhardtii. Our findings demonstrate the presence of a functional SnRK2 pathway in a chlorophyte alga, indicating that core components were established early in the green lineage. This work provides a foundation for comparative studies across green plants and underscores the need for broader taxonomic sampling to reconstruct the ancestral signaling networks underlying stress adaptation.
Project description:In our study, we found that low-passage dermal papilla cells (DPCs) and dermal sheath cells (DSCs) has higher homing rate than that of high-passage DPCs and DSCs. To uncover the molecular mechanisms underlying the difference of homing rate between low-passage DPCs/DSCs and high-passage DPCs/DSCs, we perform transcriptome analysis of mRNA expression profiles of low-passage and high-passage DPCs and DSCs.
Project description:Dermal papilla cells (DPCs) are located at the bottom of hair follicles and play important roles on hair induction by interacting with epidermal cells. DPCs are promising cell sources for hair regeneration therapy for alopecia patients. However, freshly isolated DPCs rapidly lose their hair inductive activity and proliferative potential under culture conditions. We examined the effects of telomere reverse transcriptase (TERT) and B-cell-specific Moloney murine leukemia virus insertion region 1 (BMI1) on extending the life span of murine DPCs as well as on hair inductive activity.TERT and BMI1 genes were introduced into murine DPCs using lentivirus vectors. Hair inductive activity of transfected DPCs (t-DPCs) was determined by in vivo chamber assay in nude mice. Transcripts between intact dermal papillae (DPs) and cultured DPCs were compared by microarray analysis.
Project description:Background & Aims: Cholangiocarcinomas (CCAs), heterogeneous biliary tumors with dismal prognosis, lack accurate early-diagnostic methods, especially important for individuals at high-risk (i.e., primary sclerosing cholangitis (PSC)). Here, we searched for protein biomarkers in serum extracellular vesicles (EVs). Methods: EVs from patients with isolated PSC (n=45), concomitant PSC-CCA (n=42), PSC who developed CCA during follow-up (PSC to CCA; n=25), CCAs from non-PSC etiology (n=56), hepatocellular carcinoma (n=34) and healthy individuals (n=55) were characterized by mass-spectrometry. Diagnostic biomarkers of PSC-CCA, non-PSC CCA or CCAs regardless etiology (pan-CCAs) were defined, and their expression was evaluated in human organs/tissues and within CCA tumors at single-cell level. Prognostic EV-biomarkers for CCA were investigated. Results: High-throughput proteomics identified candidate diagnostic biomarkers for PSC-CCA, non-PSC CCA or pan-CCA, as well as and for differential diagnosis of intrahepatic CCA and HCC, that were cross-validated by ELISA using total serum. Machine learning logit modelling disclosed CRP/FRIL/Fibrinogen algorithm with diagnostic value for early-stage PSC-CCA vs isolated PSC (AUC=0.944; OR=82.0), overpowering CA19-9 (AUC=0.735; OR=9.3). An algorithm combining CRP/VWF/PIGR/ /Fibrinogen allowed the diagnosis of early-stage non-PSC CCAs compared to healthy individuals (AUC=0.999; OR=1115). Noteworthy, levels of Fibrinogen/CRP/PIGR/FRIL showed predictive capacity for CCA development in patients with PSC before clinical evidences of malignancy. Multi-organ transcriptomic analysis revealed that serum EV-biomarkers were mostly expressed in hepatobiliary tissues, and scRNA-seq and immunofluorescence analysis of CCA tumors showed their presence mainly in malignant cholangiocytes. Multivariable analysis unveiled EVprognostic biomarkers independent to clinical features, with COMP/GNAI2/CFAI and ACTN1/MYCT1/PF4V associated negatively or positively to patients’ survival, respectively. Conclusions: Serum EVs contain protein biomarkers for the prediction, early diagnosis and prognosis estimation of CCA, representing a novel tumor cell-derived liquid biopsy for personalized medicine.
Project description:Hypoxia enhances the reprogramming efficiency of human dermal fibroblasts to become induced pluripotent stem cells (iPSCs). Because we showed previously that the hypoxia facilitates the isolation and maintenance of human dental pulp cells (DPCs), we examined here whether it promotes the reprogramming of DPCs to become iPSCs. To investigate the effect of oxygen concentration on global gene expression, we compared DPCs cultured for 6 days under hypoxia and normoxia.
Project description:This study determined the influence of myeloid cell Trim59 deficiency on experimental stroke outcomes and the cerebral proteomic profile using myeloid cell Trim59 conditional knockout (Trim59-cKO) mice, the middle cerebral artery occlusion/reperfusion ischemic model, and a label-free quantitative proteomic profiling technique.
Project description:Dermal papilla cells (DPCs) and epidermal hair matrix cells (HMCs) located in hair bulb are the key cell types during the hair follicles (HFs) development. To explore the mRNA and miRNA expression of DPCs and HMCs of yak hair follicle, illustrating the mocular basis of the interaction and cellular communication between DPCs and HMCs during the hair follicle development, the DPCs and HMCs of yak were isolated and cultured, RNA-seq was used to identify the differentially expressed mRNAs and miRNAs between DPCs and HMCs.