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Coronavirus 2019 (COVID-19) is a complex disease that affects billions of people worldwide. Currently, effective etiological treatment of COVID-19 is still lacking; COVID-19 also causes damages to various organs that affects therapeutics and mortality of the patients. Surveillance of the treatment responses and organ injury assessment of COVID-19 patients are of high clinical value. In this study, we investigated the characteristic fragmentation patterns and explored the potential in tissue injury assessment of plasma cell-free DNA in COVID-19 patients. Through recruitment of 37 COVID-19 patients, 32 controls and analysis of 208 blood samples upon diagnosis and during treatment, we report gross abnormalities in cfDNA of COVID-19 patients, including elevated GC content, altered molecule size and end motif patterns. More importantly, such cfDNA fragmentation characteristics reflect patient-specific physiological changes during treatment. Further analysis on cfDNA tissue-of-origin tracing reveals frequent tissue injuries in COVID-19 patients, which is supported by clinical diagnoses. Hence, our work demonstrates and extends the translational merit of cfDNA fragmentation pattern as valuable analyte for effective treatment monitoring, as well as tissue injury assessment in COVID-19.

Numerous studies have investigated the risk factors of Alzheimer’s disease (AD); however, AD-risk factors related miRNAs were rarely reported. In this study, AD-risk factor related miRNAs of 105 Chinese individuals (45 AD patients and 60 cognitively normal controls) were investigated. The results showed that Hsa-miR-185-5p, Hsa-miR-20a-5p, and Hsa-miR-497-5p were related to AD and education, Hsa-miR-185-5p, Hsa-miR-181c-5p, Hsa-miR-664a-3p, Hsa-miR-27a-3p, Hsa-miR-451a, and Hsa-miR-320a were related to AD and depression. Target prediction of above miRNAs showed that these miRNAs were involved in the generation and clearance of amyloid-beta (Aβ), important molecules related to cognition, and disease-activated microglia response to AD. It is worth noting that Hsa-miR-185-5p was related to both education and depression, whose decreased expression pattern in AD patients was alleviated by education and enhanced by depression, and participates in Aβ generation and accumulation. Our results indicated that certain education and depression factors can contribute to AD progression by modulating miRNA expression, implying that preventive interventions might alter AD progression in Chinese patients.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the pandemic of coronavirus disease 2019 (COVID-19). Great international efforts have been put into the development of prophylactic vaccines and neutralizing antibodies. However, the knowledge about the B cell immune response induced by the SARS-CoV-2 virus is still limited. Here, we report a comprehensive characterization of the dynamics of immunoglobin heavy chain (IGH) repertoire in COVID-19 patients. By using next-generation sequencing technology, we examined the temporal changes in the landscape of the patient's immunological status and found dramatic changes in the IGH within the patient's immune system after the onset of COVID-19 symptoms. Although different patients have distinct immune responses to SARS-CoV-2 infection, by employing clonotype overlap, lineage expansion, and clonotype network analyses, we observed a higher clonotype overlap and substantial lineage expansion of B cell clones 2-3 weeks after the onset of illness, which is of great importance to B-cell immune responses. Meanwhile, for preferences of V gene usage during SARS-CoV-2 infection, IGHV3-74 and IGHV4-34, and IGHV4-39 in COVID-19 patients were more abundant than those of healthy controls. Overall, we present an immunological resource for SARS-CoV-2 that could promote both therapeutic development as well as mechanistic research.

The development of spatial transcriptomics technologies has transformed genetic research from a single-cell data level to a two-dimensional spatial coordinate system and facilitated the study of the composition and function of various cell subsets in different environments and organs. The large-scale data generated by these spatial transcriptomics technologies, which contains spatial gene expression information, have elicited the need for spatially resolved approaches to meet the requirements of computational and biological data interpretation. These requirements include dealing with the explosive growth of data to determine the cell-level and gene-level expression, correcting the inner batch effect and loss of expression to improve the data quality, conducting efficient interpretation and in-depth knowledge mining both at the single-cell and tissue-wide levels, and conducting multi-omics integration analysis to provide an extensible framework towards the in-depth understanding of biological processes. However, algorithms designed specifically for spatial transcriptomics technologies to meet these requirements are still in their infancy. Here, we review computational approaches to these problems in light of corresponding issues and challenges, and present forward-looking insights into algorithm development.

The leading edge of genome editing, driven by CRISPR/Cas technology, is revolutionizing biotechnologies. In pace with the burst of novel genome editing methods, bioinformatic tools to monitor the on/off-target events need to be more evolved as well. Existing tools suffer from limitations in speed and scalability, and they especially struggle with whole genome sequencing (WGS) data analysis which has the potential to detect off-target mutations at a genome-wide level via an unbiased manner. Here, we introduce our CRISPR-detector tool, which is a web-hosted or locally deployable pipeline with five key innovations: 1) optimized scalability allowing for WGS data analysis beyond BED (Browser Extensible Data) file-defined regions; 2) improved accuracy benefiting from haplotype-based variant calling to handle sequencing errors; 3) treated and control sample co-analysis to remove background variants existing prior to genome editing; 4) integrated structural variation (SV) calling; and 5) functional and clinical annotation of editing-induced mutations.

Numerous studies have investigated the risk factors of Alzheimer’s disease (AD), however, AD- risk factors related miRNAs were rarely reported. In this study, AD- risk factor related miRNAs of 119 Chinese individuals (47 AD patients and 62 cognitively normal controls) were investigated. The results showed that education, tea consumption, leisure activity, and social connection were low Body Mass Index (BMI), depression, and smoking were potentially risk factors for AD patients. Moreover, we screened exosome microRNAs (miRNAs) for the aforementioned lifestyle-related factors. Canonical correlation analyses revealed that our clinical observations were correlated with the miRNA expression profile for education, depression, leisure activity, and social connection. Furthermore, we predicted the targets of differentially expressed miRNAs and found that many of them were reported to be involved in the generation and clearance of Amyloid-beta (Aβ), important molecules related to cognition, and disease-activated microglia response to AD. Our results indicated that certain education and depression factors can contribute to AD progression by modulating miRNA expression, implying that preventive interventions might alter AD progression in Chinese patients.

COVID-19 is a huge threat to global health. Due to the lack of definitive etiological therapeutics currently, effective disease monitoring is of high clinical value for better healthcare and management of the large number of COVID-19 patients. In this study, we recruited 37 COVID-19 patients, collected 176 blood samples upon diagnosis and during treatment, and analyzed cell-free DNA (cfDNA) in these samples. We report gross abnormalities in cfDNA of COVID-19 patients, including elevated GC content, altered molecule size and end motif patterns. More importantly, such cfDNA characteristics reflect patient-specific physiological conditions during treatment. Further analysis on tissue origin tracing of cfDNA reveals frequent tissue injuries in COVID-19 patients, which is supported by clinical diagnoses. Hence, we demonstrate the translational merit of cfDNA as valuable analyte for effective disease monitoring, as well as tissue injury assessment in COVID-19 patients.

Mutated KRAS promotes the activation of the MAPK pathway and the progression of colorectal cancer (CRC) cells. Aberrant activation of the PI3K pathway strongly attenuates the efficacy of MAPK suppression in KRAS‐mutated CRC. The development of a novel strategy targeting a dual pathway is therefore highly essential for the therapy of KRAS‐mutated CRC. In this study, a quadruple‐depleting system for the KRAS, MEK1, PIK3CA, and MTOR genes based on CRISPR/SaCas9 was developed. Adenovirus serotype 5 (ADV5) was integrated with two engineered proteins, an adaptor and a protector, to form ADV‐protein complex (APC) for systemic delivery of the CRISPR system. Quadruple‐editing could significantly inhibit the MAPK and PI3K pathways in CRC cells with oncogenic mutations of KRAS and PIK3CA or with KRAS mutation and compensated PI3K activation. Compared with MEK and PI3K/MTOR inhibitors, quadruple‐editing induced more significant survival inhibition on primary CRC cells with oncogenic mutations of KRAS and PIK3CA. The adaptor specifically targeting EpCAM and the hexon‐shielding protector could dramatically enhance ADV5 infection efficiency to CRC cells and significantly reduce off‐targeting tropisms to many organs except the colon. Moreover, quadruple‐editing intravenously delivered by APC significantly blocked the dual pathway and tumor growth of KRAS‐mutated CRC cells, without influencing normal tissues in cell‐ and patient‐derived xenograft models. Therefore, APC‐delivered quadruple‐editing of the MAPK and PI3K pathways shows a promising therapeutic potential for KRAS‐mutated CRC., Aberrant activation of the PI3K pathway interferes with the therapeutic efficacies of MAPK signaling inhibitors in KRAS‐mutated colorectal cancer (CRC). However, overlapping toxicities of small molecule inhibitors limit the treatment effects of combined therapy targeting the MAPK and PI3K pathways. Multiplex genome editing may provide a novel dual‐inhibition strategy for KRAS‐mutated CRC. A quadruple‐depleting system of KRAS, MEK1, PIK3CA, and MTOR based on CRISPR/SaCas9, which were packaged by ADV5 and integrated with two engineered proteins, an adaptor and a protector, to enhance infection efficiency and specificity to CRC cells, could effectively and specifically block tumor progression of KRAS‐mutated CRC models through systemic delivery without vital organ injury, providing a potential option for CRC therapy.

Background Mutated KRAS promotes the activation of mitogen-activated protein kinase (MAPK) pathway and the progression of colorectal cancer (CRC) cells. Aberrant activation of phosphatidylinositol 3‑kinase (PI3K) pathway strongly attenuates the efficacy of MAPK suppression in KRAS-mutated CRC cells. The development of a novel strategy targeting dual-pathway is therefore highly essential for the therapy of KRAS-mutated CRC cells. Methods In this study, a quadruple-depleting system for KRAS, MEK1, PIK3CA, and mammalian target of rapamycin (MTOR) genes based on Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/SaCas9 was developed. Serotype 5 of adenovirus (ADV5) was used as packaging virus for systemic delivery of the CRISPR system. To enhance infection efficiency and specificity of ADV5 to CRC cells and reduce its non-specific tissue tropism, two engineered proteins, an adaptor and a protector were synthesized and formed an ADV-protein complex (APC) when delivered the quadruple-editing system intravenously in vivo. Results The quadruple-editing significantly inhibited MAPK and PI3K pathways in CRC cells with oncogenic mutations of KRAS and PIK3CA or with KRAS mutation and compensated PI3K activation. Compared with MEK and PI3K/MTOR inhibitors, the quadruple-editing induced more significant survival inhibition on primary CRC cells with oncogenic mutations of KRAS and PIK3CA. The adaptor protein which specifically targeting epithelial cell adhesion molecule (EpCAM) could dramatically enhance infection efficiency of ADV5 to CRC cells. and the protector protein could significantly reduce the off-targeting tropisms in a variety of organs. Moreover, the quadruple-editing intravenously delivered by APC significantly blocked dual-pathway and tumor growth, without influencing normal tissues in cell- and patient-derived xenograft models of KRAS-mutated CRC cells. Conclusions APC-delivered quadruple-editing of MAPK and PI3K pathways effectively and specifically blocked the progression of KRAS-mutated CRC cells.

SUMMARY COVID-19 is a severe infectious disease that is a current global health threat. However, little is known about its hallmarks compared to other infectious diseases. Here, we report the single-cell transcriptional landscape of longitudinally collected peripheral blood mononuclear cells (PBMCs) in both COVID-19 and influenza A virus (IAV)-infected patients. We observed increase of plasma cells in both COVID-19 and IAV patients, and XAF1-, TNF- and FAS-induced T cell apoptosis in COVID-19 patients. Further analyses revealed distinct signaling pathways activated in COVID-19 (STAT1 and IRF3) vs. IAV (STAT3 and NFκB) patients and substantial differences in the expression of key factors. These factors include relatively increase of IL6R and IL6ST expression in COVID-19 patients, but similarly increased IL-6 concentrations compared to IAV patients, supporting the clinical observations of increased pro-inflammatory cytokines in COVID-19 patients. Thus, we provide the landscape of PBMCs and unveil distinct immune response pathways in COVID-19 and IAV patients., Graphical Abstract, Highlights ● We generated a single-cell atlas of PBMCs in both COVID-19 and influenza patients. ● Plasma cells increase significantly in both COVID-19 and influenza patients. ● COVID-19 is featured with XAF1-, TNF- and FAS-induced T cell apoptosis. ● Distinct pathways activate in COVID-19 (STAT1/IRF3) vs. influenza (STAT3/NFκB) patients., COVID-19 and influenza are both respiratory infections with cytokine release syndrome. Zhu et al. use single-cell RNA sequencing of longitudinally collected PBMCs in both patients to reveal distinct immune response landscapes of the two diseases and identify virus-specific cell composition and immune response pathways.

Single cell approaches have increased our knowledge about the cell type composition of the non-human primate (NHP), but a detailed characterization of area-specific regulatory features remains outstanding. We generated single-cell chromatin accessibility (single-cell ATAC) and transcriptomic data of 358,237 cells from prefrontal cortex (PFC), primary motor cortex (M1) and primary visual cortex (V1) of adult cynomolgus monkey brain, and integrated this dataset with Stereo-seq (Spatio-Temporal Enhanced REsolution Omics-sequencing) of the corresponding cortical areas to assign topographic information to molecular states. We identified area-specific chromatin accessible sites and their targeted genes, including the cell type-specific transcriptional regulatory network associated with excitatory neurons heterogeneity. We reveal calcium ion transport and axon guidance genes related to specialized functions of PFC and M1, identified the similarities and differences between adult macaque and human oligodendrocyte trajectories, and mapped the genetic variants and gene perturbations of human diseases to NHP cortical cells. This resource establishes a transcriptomic and chromatin accessibility combinatory regulatory landscape at a single-cell and spatially resolved resolution in NHP cortex.

Stopping COVID-19 is a priority worldwide. Understanding which cell types are targeted by SARS-CoV-2 virus, whether interspecies differences exist, and how variations in cell state influence viral entry is fundamental for accelerating therapeutic and preventative approaches. In this endeavor, we profiled the transcriptome of nine tissues from a Macaca fascicularis monkey at single-cell resolution. The distribution of SARS-CoV-2 facilitators, ACE2 and TMRPSS2, in different cell subtypes showed substantial heterogeneity across lung, kidney, and liver. Through co-expression analysis, we identified immunomodulatory proteins such as IDO2 and ANPEP as potential SARS-CoV-2 targets responsible for immune cell exhaustion. Furthermore, single-cell chromatin accessibility analysis of the kidney unveiled a plausible link between IL6-mediated innate immune responses aiming to protect tissue and enhanced ACE2 expression that could promote viral entry. Our work constitutes a unique resource for understanding the physiology and pathophysiology of two phylogenetically close species, which might guide in the development of therapeutic approaches in humans.Bullet pointsWe generated a single-cell transcriptome atlas of 9 monkey tissues to study COVID-19.ACE2+TMPRSS2+ epithelial cells of lung, kidney and liver are targets for SARS-CoV-2.ACE2 correlation analysis shows IDO2 and ANPEP as potential therapeutic opportunities.We unveil a link between IL6, STAT transcription factors and boosted SARS-CoV-2 entry.

Summary Osteoglossiformes is a basal clade of teleost, evolving since the Jurassic period. The genomes of Osteoglossiformes species would shed light on the evolution and adaptation of teleost. Here, we established a chromosome-level genome of African arowana. Together with the genomes of pirarucu and Asian arowana, we found that they diverged at ∼106.1 million years ago (MYA) and ∼59.2 MYA, respectively, which are coincident with continental separation. Interestingly, we identified a dynamic genome evolution characterized by a fast evolutionary rate and a high pseudogenization rate in African arowana and pirarucu. Additionally, more transposable elements were found in Asian arowana which confer more gene duplications. Moreover, we found the contraction of olfactory receptor and the expansion of UGT in African arowana might be related to its transformation from carnivore to be omnivore. Taken together, we provided valuable genomic resource of Osteoglossidae and revealed the correlation of biogeography and teleost evolution., Graphical Abstract, Highlights • An evolutionary model of Osteoglossidae along the continental drift is provided • A faster evolving rate of African arowana than Asian arowana is revealed • The gene duplications of Asian arowana are related to more class I TE insertions • A mechanism of African arowana’s feeding habits transition is proposed., Evolutionary Biology; Phylogenetics; Paleobiology; Paleogenetics

Background Rhizomatousness is a key component of perenniality of many grasses that contribute to competitiveness and invasiveness of many noxious grass weeds, but can potentially be used to develop perennial cereal crops for sustainable farmers in hilly areas of tropical Asia. Oryza longistaminata, a perennial wild rice with strong rhizomes, has been used as the model species for genetic and molecular dissection of rhizome development and in breeding efforts to transfer rhizome-related traits into annual rice species. In this study, an effort was taken to get insights into the genes and molecular mechanisms underlying the rhizomatous trait in O. longistaminata by comparative analysis of the genome-wide tissue-specific gene expression patterns of five different tissues of O. longistaminata using the Affymetrix GeneChip Rice Genome Array. Results A total of 2,566 tissue-specific genes were identified in five different tissues of O. longistaminata, including 58 and 61 unique genes that were specifically expressed in the rhizome tips (RT) and internodes (RI), respectively. In addition, 162 genes were up-regulated and 261 genes were down-regulated in RT compared to the shoot tips. Six distinct cis-regulatory elements (CGACG, GCCGCC, GAGAC, AACGG, CATGCA, and TAAAG) were found to be significantly more abundant in the promoter regions of genes differentially expressed in RT than in the promoter regions of genes uniformly expressed in all other tissues. Many of the RT and/or RI specifically or differentially expressed genes were located in the QTL regions associated with rhizome expression, rhizome abundance and rhizome growth-related traits in O. longistaminata and thus are good candidate genes for these QTLs. Conclusion The initiation and development of the rhizomatous trait in O. longistaminata are controlled by very complex gene networks involving several plant hormones and regulatory genes, different members of gene families showing tissue specificity and their regulated pathways. Auxin/IAA appears to act as a negative regulator in rhizome development, while GA acts as the activator in rhizome development. Co-localization of the genes specifically expressed in rhizome tips and rhizome internodes with the QTLs for rhizome traits identified a large set of candidate genes for rhizome initiation and development in rice for further confirmation.