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Wu, E.

Publications and source records attributed to Wu, E..

46 records · Page 3Linked to original sources

Nanog organizes transcription bodies

The localization of transcriptional activity in specialized transcription bodies is a hallmark of gene expression in eukaryotic cells. How proteins of the transcriptional machinery come together to form such bodies, however, is unclear. Here, we take advantage of two large, isolated, and long-lived transcription bodies that reproducibly form during early zebrafish embryogenesis, to characterize the dynamics of transcription body formation. Once formed, these transcription bodies are enriched for initiating and elongating RNA polymerase II, as well as the transcription factors Nanog and Sox19b. Analyzing the events leading up to transcription, we find that Nanog and Sox19b cluster prior to transcription, and independently of RNA accumulation. The clustering of transcription factors is sequential; Nanog clusters first, and this is required for the clustering of Sox19b and the initiation of transcription. Mutant analysis revealed that both the DNA-binding domain, as well as one of the two intrinsically disordered regions of Nanog are required to organize the two bodies of transcriptional activity. Taken together, our data suggests that the clustering of transcription factors dictates the formation of transcription bodies. HIGHLIGHTSO_LITranscription factors cluster prior to, and independently of transcription C_LIO_LINanog organizes transcription bodies: it is required for the clustering of Sox19b as well as RNA polymerase II C_LIO_LIThis organizing activity requires its DNA binding domain as well as one of its intrinsically disordered regions C_LIO_LITranscription elongation results in the disassembly of transcription factor clusters C_LI

cell biology↗

7-UP: generating in silico CODEX from a small set of immunofluorescence markers

Multiplex immunofluorescence (mIF) assays multiple protein biomarkers on a single tissue section. Recently, high-plex CODEX (co-detection by indexing) systems enable simultaneous imaging of 40+ protein biomarkers, unlocking more detailed molecular phenotyping, leading to richer insights into cellular interactions and disease. However, high-plex imaging can be slower and more costly to collect, limiting its applications, especially in clinical settings. We propose a machine learning framework, 7-UP, that can computationally generate in silico 40-plex CODEX at single-cell resolution from a standard 7-plex mIF panel by leveraging cellular morphology. We demonstrate the usefulness of the imputed biomarkers in accurately classifying cell types and predicting patient survival outcomes. Furthermore, 7-UPs imputations generalize well across samples from different clinical sites and cancer types. 7-UP opens the possibility of in silico CODEX, making insights from high-plex mIF more widely available.

bioinformatics↗

SPACE-GM: geometric deep learning of disease-associated microenvironments from multiplex spatial protein profiles.

Multiplexed immunofluorescence imaging enables high-dimensional molecular profiling at subcellular resolution. However, learning disease-relevant cellular environments from these rich imaging data is an open challenge. We developed SPAtial CEllular Graphical Modeling (SPACE-GM), a geometric deep learning framework that flexibly models tumor microenvironments (TMEs) as cellular graphs. We applied SPACE-GM to 658 head-and-neck and colorectal human cancer samples assayed with 40-plex immunofluorescence imaging to identify spatial motifs associated with cancer recurrence and patient survival after immunotherapy. SPACE-GM is substantially more accurate in predicting patient outcomes than previous approaches for modeling spatial data using neighborhood cell-type compositions. Computational interpretation of the disease-relevant microenvironments identified by SPACE-GM generates insights into the effect of spatial dispersion of tumor cells and granulocytes on patient prognosis.

bioinformatics↗

Wuschel2 enables highly efficient CRISPR/Cas-targeted genome editing during rapid de novo shoot regeneration in sorghum

For many important crops, including sorghum, the use of CRISPR/Cas technology is limited not only by the delivery of the gene-modification components into a plant cell, but more critically, by the ability to regenerate a fertile plant from the engineered cell through conventional tissue culture methods. Here, we report that Wuschel2 (Wus2)-enabled sorghum (Sorghum bicolor L.) transformation increases not only the efficiency of transgenic plant recovery, but also increases the observed efficiency of CRISPR/Cas-targeted genome editing within the population of T0 plants. Using Agrobacterium-mediated transformation, we have demonstrated Wus2-induced direct somatic embryo formation and regeneration, bypassing genotype-dependent callus formation and significantly shortening the tissue culture cycle time. This method also increased regeneration capacity, resulting in higher transformation efficiency across different sorghum genotypes. Subsequently, advanced excision systems and "altruistic" transformation technology have been developed to generate high-quality morphogenic gene-free and/or selectable marker-free sorghum events. Finally, we demonstrated up to an additional 6.8-fold increase in CRISPR/Cas9-mediated gene dropout frequency using Wus2-enabled, Agrobacterium-mediated transformation (compared to the control treatment with no Wus2), across various targeted loci in different sorghum genotypes. Wus2-enabled genome editing may be applicable to other crops and increasingly popular in planta transformation strategies.

developmental biology↗

The genome assembly and annotation of Magnolia biondii Pamp., a phylogenetically, economically, and medicinally important ornamental tree species

Magnolia biondii Pamp. (Magnoliaceae, magnoliids) is a phylogenetically, economically, and medicinally important ornamental tree species widely grown and cultivated in the north-temperate regions of China. Contributing a genome sequence for M. biondii will help resolve phylogenetic uncertainty of magnoliids and further understand individual trait evolution in Magnolia. We assembled a chromosome-level reference genome of M. biondii using ~67, ~175, and ~154 Gb of raw DNA sequences generated by Pacific Biosciences Single-molecule Real-time sequencing, 10X genomics Chromium, and Hi-C scaffolding strategies, respectively. The final genome assembly was 2.22 Gb with a contig N50 of 269.11 Kb and a BUSCO complete gene ratio of 91.90%. About 89.17% of the genome length was organized to 19 chromosomes, resulting in a scaffold N50 of 92.86 Mb. The genome contained 48,319 protein-coding genes, accounting for 22.97% of the genome length, in contrast to 66.48% of the genome length for the repetitive elements. We confirmed a Magnoliaceae specific WGD event that might have probably occurred shortly after the split of Magnoliaceae and Annonaceae. Functional enrichment of the Magnolia specific and expanded gene families highlighted genes involved in biosynthesis of secondary metabolites, plant-pathogen interaction, and response to stimulus, which may improve ecological fitness and biological adaptability of the lineage. Phylogenomic analyses recovered a sister relationship of magnoliids and Chloranthaceae, which are sister to a clade comprising monocots and eudicots. The genome sequence of M. biondii could empower trait improvement, germplasm conservation, and evolutionary studies on rapid radiation of early angiosperms.

plant biology↗

Comprehensive and Integrated Genomic Characterization of Human Immunome in Cancer

Genetic alterations in immune-related pathways are common hallmarks of cancer. However, to realize the full potential of immunotherapy, a comprehensive understanding of immune networks and how mutations impact network structure and functional output across cancer types is instrumental. Herein we systematically interrogated somatic mutations that could express neoantigens and alter immune responses in cancer patients compared to wild-type controls. To do so, we developed a network-based immunogenomics model (NIPPER) with scoring systems to prioritize critical genes and mutations eliciting differential HLA binding affinity and alternate responses to immunotherapy. These mutations are enriched in essential protein domains and often alter tumor infiltration by immune cells, affecting T cell receptor repertoire and B cell clonal expansion. Furthermore, we devised an interactome network propagation framework integrated with drug associated gene signatures to identify potential immunomodulatory drug candidates. Together, our systems-level analysis results help interpret the heterogeneous immune responses among patients, and serve as a resource for future functional studies and targeted therapeutics. SignificanceCancer cells induce specific immune-related pathway perturbations by mutations, transcriptional dysregulation, and integration of multi-omics data can help identify critical molecular determinants for effective targeted therapeutics.

immunology↗

Systematic characterization of somatic mutation-mediated microRNA regulatory network perturbations

Somatic mutations are a major source of cancer development. Many driver mutations have been identified in protein coding regions. However, the function of mutations located in microRNAs (miRNAs) and their target binding sites along the human genome remains largely unknown. Here, we built comprehensive cancer-specific miRNA regulatory networks across 30 cancer types to systematically analyze the effect of mutations on miRNA related pathways. 3,518,261 mutations from 9,819 samples were mapped to miRNA-gene interactions (mGI), and mutations in miRNAs versus in their target genes show a mutually exclusive pattern in almost all cancer types. Using a linear regression method, we further identified 89 driver mutations in 14 cancer types that can significantly perturb miRNA regulatory networks. We find that driver mutations play their roles by altering RNA binding energy and the expression of target genes. Finally, we demonstrate that mutated driver gene targets are significantly down-regulated in cancer and function as tumor suppressors during cancer progression, suggesting potential miRNA candidates with significant clinical implications. We provide this data resource (CanVar-mGI) through a user-friendly, open-access web portal. Together, our results will facilitate novel non-coding biomarker identification and therapeutic drug design.

bioinformatics↗

An efficient gene excision system in maize

Use of the morphogenic genes Baby Boom (Bbm) and Wuschel2 (Wus2), along with new ternary constructs, has increased the genotype range and the type of explants that can be used for maize transformation. In addition, altering the ectopic expression pattern for Bbm/Wus2 has resulted in rapid maize transformation methods that are faster and applicable to a broader range of inbreds. However, expression of Bbm/Wus2 can compromise the quality of regenerated plants, leading to sterility. We reasoned excising morphogenic genes after transformation but before regeneration would increase production of fertile T0 plants. We developed a method that uses an inducible site-specific recombinase (Cre) to excise morphogenic genes. The use of developmentally regulated promoters, such as Ole, Glb1, End2 and Ltp2, to drive Cre enabled excision of morphogenic genes in early embryo development and produced excised events at a rate of 25%-100%. A different strategy utilizing an excision-activated selectable marker produced excised events at a rate of 53.3%-68.4%; however, the transformation frequency was lower (12.9%-49.9%). The use of inducible heat shock promoters (e.g. Hsp17.7, Hsp26) to express Cre, along with improvements in tissue culture conditions and construct design, resulted in high frequencies of T0 transformation (29%-69%), excision (50%-97%), usable quality events (3.6%-14%), and few escapes (non-transgenic; 14%-17%) in three elite maize inbreds. Transgenic events produced by this method are free of morphogenic and marker genes.

plant biology↗

Efficient Gene Targeting in Maize using Inducible CRISPR-Cas9 and Marker-Free Donor Template

CRISPR-Cas9 is a powerful tool for generating targeted mutations and genomic deletions. However, precise gene insertion or sequence replacement remains a major hurdle before application of CRISPR-Cas9 technology is fully realized in plant breeding. Here we report high frequency, selectable marker-free intra-genomic gene targeting (GT) in maize. Heat shock-inducible Cas9 was used for generating targeted double-strand breaks (DSBs) and simultaneous mobilization of the donor template from pre-integrated T-DNA. The construct was designed such that release of the donor template and subsequent DNA repair activated expression of the selectable marker gene within the donor locus. This approach generated up to 4.7% targeted insertion of the donor sequence into the target locus in T0 plants, with up to 86% detected donor template release and 99% mutation rate were observed at the donor loci and the genomic target site, respectively. Unlike previous in planta or intra-genomic homologous recombination reports, that required multiple generations and extensive screening, our method provides non-chimeric, heritable GT in the T0 generation.

plant biology↗

Spread of pathological α-synuclein from urogenital nerves initiates multiple system atrophy-like symptoms

Multiple system atrophy (MSA) is a fatal adult-onset movement disorder with autonomic failures, especially urogenital dysfunction. The neuropathological feature of MSA is the accumulation of misfolded -synuclein (-Syn) in the nervous system. Here, we show that misfolded -Syn exist in nerve terminals in detrusor (DET) and external urethral sphincter (EUS) of patients with MSA. Moreover, -Syn preformed fibrils inoculated into the EUS or DET in TgM83+/- mice initiated the transmission of misfolded -Syn from the lower urinary tract to brain, and these mice developed -Syn inclusion pathology through micturition reflex pathways along with urinary dysfunction and motor impairments. These findings indicate that spreading of misfolded -Syn from the autonomic control of the lower urinary tract to the brain via micturition reflex pathways induces autonomic failure and motor impairments. These results provide important new insights into the pathogenesis of MSA as well as highlight potential targets for early detection and therapeutics.

neuroscience↗