关键词： heart failure   acute   iron   quality of life  

摘要： This commentary refers to ‘The effect of intravenous ferric carboxymaltose on health-related quality of life in iron-deficient patients with acute heart failure: the results of the AFFIRM-AHF study’, by E.A. Jankowska et al. , https://***/10.1093/eurheartj/ehab234 and the discussion piece ‘Dilemmas on diagnosis and treatment of iron deficiency in patients after an episode of acute heart failure’, by E.A. Jankowska and P. Ponikowski, https://***/10.1093/eurheartj/ehab839 .

关键词： mRNA variants   5'UTR   Coat color   Gene expression   Alternative splicing  

摘要： The Agouti gene (ASIP) is one of the most important genes for coat color determination in mammals. It has a complex structure with several promoters and alternative non-coding first exons that are transcribed into mRNAs with different 5'UTR. These mRNA isoforms regulate the temporal and spatial expression of the gene, producing diverse pigmentation patterns. Here, we studied ASIP transcriptional variants and their expression in the skin of llamas with different coat color phenotypes. We also described the ASIP locus, including promoter usage and the splicing events that originate each transcript variant. Using 5'RACE-PCR we isolated seven ASIP transcripts with alternative 5'UTR, where exons 1A, 1A', 1C, 1D, and a novel non-coding exon 1A" were identified. Additionally, new alternative spliced forms were found. The diversity of ASIP 5'UTRs is originated by a complex pattern of alternative promoter usage, multiple transcription start sites and splicing events that include exon skipping and alternative 3' splicing site selection. We found that ASIP was highly expressed in llamas with white and brown phenotypes while black animals presented very low expression. The main responsible for this difference was a fusion transcript between ASIP and NCOA6 genes, which was present in the skin of white and brown llamas but not in the black ones. The rest of ASIP transcripts presented very low expression in the skin, indicating that the main regulation point for ASIP gene expression is at the transcriptional level. Nevertheless, the characteristics of the 5'UTRs sequences suggest that alternative transcripts could be regulated differently at the protein synthesis level.

关键词： Mechanisms of disease   Proteomic analysis   Life Sciences   general   Cell Biology  

摘要： Host cellular receptors play key roles in the determination of virus tropism and ***,little is known about SARS-CoV-2 host receptors with the exception of ***,ACE2 alone cannot explain the multi-organ tropism of SARS-CoV-2 nor the clinical differences between SARS-CoV-2 and SARS-CoV,suggesting the involvement of other receptor(s).Here,we performed genomic receptor profiling to screen 5054 human membrane proteins individually for interaction with the SARS-CoV-2 capsid spike (S) *** proteins,including ACE2,ASGR1,and KREMEN1,were identified with diverse S-binding affinities and ***1 or KREMEN1 is sufficient for the entry of SARS-CoV-2 but not SARS-CoV in vitro and in ***-CoV-2 utilizes distinct ACE2/ASGR1/KREMEN1 (ASK) receptor combinations to enter different cell types,and the expression of ASK together displays a markedly stronger correlation with Virus susceptibility than that of any individual receptor at both the cell and tissue *** cocktail of ASK-related neutralizing antibodies provides the most substantial blockage of SARS-CoV-2 infection in human lung organoids when compared to individual *** study revealed an interacting host receptome of SARS-CoV-2,and identified ASGR1 and KREMEN1 as alternative functional receptors that play essential roles in ACE2-independent virus entry,providing insight into SARS-CoV-2 tropism and pathogenesis,as well as a community resource and potential therapeutic strategies for further COVID-19 investigations.

摘要： Covering: up to 2021 Terpenoids are a diverse group of chemicals used in a wide range of industries. Microbial terpenoid production has the potential to displace traditional manufacturing of these compounds with renewable processes, but further titre improvements are needed to reach cost competitiveness. This review discusses strategies to increase terpenoid titres in Escherichia coli with a focus on alternative metabolic pathways. Alternative pathways can lead to improved titres by providing higher orthogonality to native metabolism that redirects carbon flux, by avoiding toxic intermediates, by bypassing highly-regulated or bottleneck steps, or by being shorter and thus more efficient and easier to manipulate. The canonical 2-C-methyl-d-erythritol 4-phosphate (MEP) and mevalonate (MVA) pathways are engineered to increase titres, sometimes using homologs from different species to address bottlenecks. Further, alternative terpenoid pathways, including additional entry points into the MEP and MVA pathways, archaeal MVA pathways, and new artificial pathways provide new tools to increase titres. Prenyl diphosphate synthases elongate terpenoid chains, and alternative homologs create orthogonal pathways and increase product diversity. Alternative sources of terpenoid synthases and modifying enzymes can also be better suited for E. coli expression. Mining the growing number of bacterial genomes for new bacterial terpenoid synthases and modifying enzymes identifies enzymes that outperform eukaryotic ones and expand microbial terpenoid production diversity. Terpenoid removal from cells is also crucial in production, and so terpenoid recovery and approaches to handle end-product toxicity increase titres. Combined, these strategies are contributing to current efforts to increase microbial terpenoid production towards commercial feasibility.

关键词： PSMA   prostate cancer   glutamate-ureido-lysine   molecular imaging   PET  

摘要： Prostate-specific membrane antigen (PSMA) is highly overexpressed in most prostate cancers and is clinically visualized using PSMAspecific probes incorporating glutamate-ureido-lysine (GUL). PSMA is effectively absent from certain high-mortality, treatment-resistant subsets of prostate cancers, such as neuroendocrine prostate cancer (NEPC);however, GUL-based PSMA tracers are still reported to have the potential to identify NEPC metastatic tumors. These probes may bind unknown proteins associated with PSMA-suppressed cancers. We have identified the up-regulation of PSMA-like aminopeptidase NAALADaseL and the metabotropic glutamate receptors (mGluRs) in PSMA-suppressed prostate cancers and find that their expression levels inversely correlate with PSMA expression and are associated with GUL-based radiotracer uptake. Furthermore, we identify that NAALADaseL and mGluR expression correlates with a unique cell cycle signature. This provides an opportunity for the future study of the biology of NEPC and potential therapeutic directions. Computationally predicting that GUL-based probes bind well to these targets, we designed and synthesized a fluorescent PSMA tracer to investigate these proteins in vitro, where it shows excellent affinity for PSMA, NAALADaseL, and specific mGluRs associated with poor prognosis.

摘要： Posttranscriptional regulation has emerged as a driver for leukemia development and an avenue for therapeutic targeting. Among posttranscriptional processes, alternative polyadenylation (APA) is globally dysregulated across cancer types. However, limited studies have focused on the prevalence and role of APA in myeloid leukemia. Furthermore, it is poorly understood how altered poly(A) site usage of individual genes contributes to malignancy or whether targeting global APA patterns might alter oncogenic potential. In this study, we examined global APA dysregulation in patients with acute myeloid leukemia (AML) by performing 3' region extraction and deep sequencing (3'READS) on a subset of AML patient samples along with healthy hemato-poietic stem and progenitor cells (HSPCs) and by analyzing publicly available data from a broad AML patient cohort. We show that patient cells exhibit global 3' untranslated region (UTR) shortening and coding sequence lengthening due to differences in poly(A) site (PAS) usage. Among APA regulators, expression of FIP1L1, one of the core deavage and polyadenylation factors, correlated with the degree of APA dysregulation in our 3'READS data set. Targeting global APA FIP1L1 knockdown reversed the global trends seen in patients. Importantly, FIP1L1 knock down induced differentiation of t(8;21) cells by promoting 3'UTR lengthening and downregulation of the fusion oncoprotein AML1-ETO. In non-t(8;21) cells, FIP1L1 knockdown also promoted differentiation by attenuating mechanistic target of rapamydn complex 1 (mTORC1) signaling and reducing MYC protein levels. Our study provides mechanistic insights into the role of APA in AML pathogenesis and indicates that targeting global APA patterns can overcome the differentiation block in patients with AML.

摘要： Diffuse large B-cell lymphoma (DLBCL) is the most frequent lymphoid malignancy affecting adults. The NF-kappa B transcription factor family is activated by 2 main pathways, the canonical and the alternative NF-kappa B activation pathway, with different functions. The alternative NF-kappa B pathway leads to activation of the transcriptionally active RelB NF-kappa B subunit. Alternative NF-kappa B activation status and its role in DLBCL pathogenesis remain undefined. Here, we reveal a frequent activation of RelB in a large cohort of DLBCL patients and cell lines, independently of their activated B-cell-like or germinal center B-cell-like subtype. RelB activity defines a new subset of patients with DLBCL and a peculiar gene expression profile and mutational pattern. Importantly, RelB activation does not correlate with the MCD genetic subtype, enriched for activated B-cell-like tumors carrying MYD88(L265P) and CD79B mutations that cooperatively activate canonical NF-kappa B, thus indicating that current genetic tools to evaluate NF-kappa B activity in DLBCL do not provide information on the alternative NF-kappa B activation. Furthermore, the newly defined RelB-positive subgroup of patients with DLBCL exhibits a dismal outcome after immunochemotherapy. Functional studies revealed that RelB confers DLBCL cell resistance to DNA damage-induced apoptosis in response to doxorubicin, a genotoxic agent used in the front-line treatment of DLBCL. We also show that RelB positivity is associated with high expression of cellular inhibitor of apoptosis protein 2 (cIAP2). Altogether, RelB activation can be used to refine the prognostic stratification of DLBCL and may contribute to subvert the therapeutic DNA damage response in a segment of patients with DLBCL.

关键词： 4-exo-dig   allenes   cascade reactions   cyclocarbopalladation   cyclooctatrienes  

摘要： The 4-exo-dig cyclocarbopalladation of vinyl bromides substituted with a triple or double bond resulted in impressive cascade reactions leading to different compounds under Suzuki cross-coupling conditions upon a slight modification of the starting material. When the starting compound carries a triple bond, a single cascade occurs providing a structure containing an allene, a tetrasubstituted cyclopropane, and a cyclobutene with complete stereoselectivity. When the related starting material possessing a double bond is reacted under the same conditions in the presence of various vinyl boronic esters or acids, an efficient 8 pi-electrocyclization provides tricyclic systems comprised of a cyclobutene unit, as well as a cyclooctatriene. Five carbons of the latter can be selectively decorated with different substituents depending on the choice of the starting material and the boronic coupling partner.

关键词： gene expression   transcription   genetic   cells   genes   polyadenylation   rna   small cytoplasmic   rna-binding proteins   mice   micrornas   rna-seq  

摘要： Alternative polyadenylation (APA) has been widely recognized as a crucial step during the posttranscriptional regulation of eukaryotic genes. Recent studies have demonstrated that APA exerts key regulatory roles in many biological processes and often occurs in a tissue- and cell-type-specific manner. However, to our knowledge, there is no database incorporating information about APA at the celltype level. Single-cell RNA-seq is a rapidly evolving and powerful tool that enable APA analysis at the cell-type level. Here, we present a comprehensive resource, scAPAatlas (http://***: 3838/scAPAatlas), for exploring APA across different cell types, and interpreting potential biological functions. Based on the curated scRNA-seq data from 24 human and 25 mouse normal tissues, we systematically identified cell-type-specific APA events for different cell types and examined the correlations between APA and gene expression level. We also estimated the crosstalk between cell-type-specific APA events and microRNAs or RNA-binding proteins. A user-friendly web interface has been constructed to support browsing, searching and visualizing multilayer information of cell-type-specific APA events. Overall, scAPAatlas, incorporating a rich resource for exploration of APA at the cell-type level, will greatly help researchers chart cell type with APA and elucidate the biological functions of APA.

关键词： actins   alternative splicing   human embryonic stem cells   sarcomeres   transcriptome  

摘要： Background: Mutations in genes encoding sarcomeric proteins lead to failures in sarcomere assembly, the building blocks of contracting muscles, resulting in cardiomyopathies that are a leading cause of morbidity and mortality worldwide. Splicing variants of sarcomeric proteins are crucial at different stages of myofibrillogenesis, accounting for sarcomeric structural integrity. RBM24 (RNA-binding motif protein 24) is known as a tissue-specific splicing regulator that plays an essential role in cardiogenesis. However, it had been unclear if the developmental stage-specific alternative splicing facilitated by RBM24 contributes to sarcomere assembly and cardiogenesis. Our aim is to study the molecular mechanism by which RBM24 regulates cardiogenesis and sarcomere assembly in a temporal-dependent manner. Methods: We ablated RBM24 from human embryonic stem cells (hESCs) using CRISPR/Cas9 techniques. Results: Although RBM24(-/-) hESCs still differentiated into sarcomere-hosting cardiomyocytes, they exhibited disrupted sarcomeric structures with punctate Z-lines due to impaired myosin replacement during early myofibrillogenesis. Transcriptomics revealed >4000 genes regulated by RBM24. Among them, core myofibrillogenesis proteins (eg, ACTN2 [alpha-actinin 2], TTN [titin], and MYH10 [non-muscle myosin IIB]) were misspliced. Consequently, MYH6 (muscle myosin II) cannot replace nonmuscle myosin MYH10, leading to myofibrillogenesis arrest at the early premyofibril stage and causing disrupted sarcomeres. Intriguingly, we found that the ABD (actin-binding domain;encoded by exon 6) of the Z-line anchor protein ACTN2 is predominantly excluded from early cardiac differentiation, whereas it is consistently included in human adult heart. CRISPR/Cas9-mediated deletion of exon 6 from ACTN2 in hESCs, as well as forced expression of full-length ACTN2 in RBM24(-/-) hESCs, further corroborated that inclusion of exon 6 is critical for sarcomere assembly. Overall, we have demonstrated that RB