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Biology subjects

Yoda, T.

Publications and source records attributed to Yoda, T..

8 recordsLinked to original sources

Multimodal alignments of in vivo imaging and spatial biology datasets at cellular resolution

Parallel revolutions in intravital microscopy and spatial biology techniques have respectively enabled large-scale recordings of cellular dynamics in live animals and multi-dimensional molecular profiling at single-cell resolution. However, due to the challenges of aligning data from different modalities at cellular resolution, these two transformational approaches have generally been applied on separate biological samples, stymying the ability to link activity patterns and molecular attributes in the same exact cells. To enable routine, multimodal investigations of cells in vivo dynamics and molecular content, we created TRU-FACT (Total Registration Under Functional Activity, Connectivity, and Transcriptomics), a broadly applicable experimental and computational pipeline for registering large populations of individual cells across intravital imaging and spatial biology datasets. The pipeline combines three key innovations: an optomechanical tissue handling and alignment method to parallelize specimen planes, a graph-theoretic method to register individual cells based on their geometric relationships to neighboring cells, and a statistical framework that provides for each cell an a posteriori probability of correct registration. We validated TRU-FACT with several preparations for imaging neural Ca2+ activity in cortical and deep brain areas in head-fixed and freely behaving mice, RNA-barcode-expressing viruses for labeling neural projections, and low- and high-plex spatial transcriptomic methods. In mice performing a skilled reaching task, TRU-FACT alignments revealed the movement-related signaling patterns of intratelencephalic, extratelencephalic, and striatum-, superior colliculus-, and thalamus-projecting motor cortical neurons. Overall, TRU-FACT constitutes a scalable, multimodal discovery platform that is applicable to diverse tissue-types and spatial biology techniques, thereby enabling multiscale analyses of many complex biological systems.

neuroscience↗

Blocky proline/glutamine patterns in the SFPQ intrinsically disordered region dictate paraspeckle formation as a distinct membraneless organelle

Membraneless organelles (MLOs) formed through phase separation play crucial roles in various cellular processes. Many MLOs remain spatially compartmentalized, avoiding fusion or engulfment. MLOs are formed by dynamic multivalent interactions, often mediated by proteins with intrinsically disordered regions (IDRs). However, the molecular principles behind how IDRs maintain MLO independence remain poorly understood. Here, we investigated the proline/glutamine (P/Q)-rich IDR of SFPQ, a protein identified as a key factor in segregating paraspeckles from nuclear speckles. Paraspeckle segregation analyses, using SFPQ mutants tethered to NEAT1_2 long noncoding RNA, revealed that P/Q residues within the SFPQ IDR, conserved from humans to zebrafish, are crucial for its segregation activity. Beyond amino acid composition, the blocky patterns of P/Q residues are required for the segregation from nuclear speckles. Among human IDRs exhibiting PQ-block patterns, BRD4 IDR shows strong sequence similarity to the SFPQ IDR, and exhibits comparable segregation activity. Molecular dynamics simulation suggests that the PQ-blocky patterns required for the paraspeckle segregation do not correlate with the IDR characteristics necessary for self-assembly. Thus, these data suggest that the PQ-blocky patterns in IDRs represent a previously uncharacterized property that contributes to MLO independence, possibly through a mechanism distinct from the conventional phase separation-promoting function of IDRs.

molecular biology↗

Four-color single-molecule imaging system for tracking GPCR dynamics with fluorescent HiBiT peptide

Single-molecule imaging provides information on diffusion dynamics, oligomerization, and protein-protein interactions in living cells. To simultaneously monitor different types of proteins at the single-molecule level, orthogonal fluorescent labeling methods with different photostable dyes are required. G-protein-coupled receptors (GPCRs), a major class of drug targets, are prototypical membrane receptors that have been studied using single-molecule imaging techniques. Here we developed a method for labeling cell-surface GPCRs inspired by the HiBiT system, which utilizes the high affinity complementation between LgBiT and HiBiT fragments of the NanoLuc luciferase. We synthesized four fluorescence-labeled HiBiT peptides (F-FiBiTs) with a different color dye (Setau-488, TMR, SaraFluor 650 and SaraFluor 720). We constructed a multicolor total internal reflection fluorescence microscopy system that allows us to track four color dyes simultaneously. As a proof-of-concept experiment, we labeled an N-terminally LgBiT-fused GPCR (Lg-GPCR) with a mixture of the four F-FiBiTs and successfully tracked each dye within a cell at the single molecule level. The F-FiBiT-labeled Lg-GPCRs showed agonist-dependent changes in the diffusion dynamics and accumulation into the clathrin-coated pits as observed with a conventional method using a C-terminally HaloTag-fused GPCR. Taking advantage of luciferase complementation by the F-FiBiT and Lg-GPCRs, the F-FiBiT was also applicable to bioluminescence plate-reader-based assays. By combining existing labeling methods such as HaloTag, SNAP-tag, and fluorescent proteins, the F-FiBiT method will be useful for multicolor single-molecule imaging and will enhance our understanding of GPCR signaling at the single-molecule level.

biophysics↗

Uncovering novel endolysins against methicillin-resistant Staphylococcus aureus using microbial single-cell genome sequencing

Endolysins, peptidoglycan hydrolases derived from bacteriophages (phages), are being developed as a promising alternative to conventional antibiotics. To obtain highly active endolysins, a diverse library of endolysins is vital. We here propose microbial single-cell genome sequencing as an efficient tool to discover dozens of previously unknown endolysins, owing to its culture-independent sequencing method. As a proof-of-concept, we analyzed and recovered endolysin genes within prophage regions of Staphylococcus single-amplified genomes (SAGs) in human skin microbiome samples. We constructed a library of chimeric endolysins by shuffling domains of the natural endolysins and performed high-throughput screening against Staphylococcus aureus. One of the lead endolysins, bbst1027, exhibited desirable antimicrobial properties such as rapid bactericidal activity, no detectable resistance development, and in vivo efficacy. We foresee that this endolysin discovery pipeline is in principle applicable to any bacterial target, and boost the development of novel antimicrobial agents.

microbiology↗

Revealing within-species diversity in uncultured human gut bacteria with single-cell long-read sequencing

Bacterial genome structure changes dynamically, and structural variants can change bacterial phenotype; However, obtaining the complete genome and analyzing genome structure of uncultured bacteria has been challenging. We aimed to develop a single-cell amplified genome long-read assembly (scALA) workflow to construct circular single-cell amplified genomes (cSAGs) from long-read single-cell sequencing data of targeted uncultured bacteria. In particular, scALA generated cSAGs from nanopore long-read sequencing data of SAGs by producing contiguous sequences with repeated bias reduction and assembly processes. From 12 human fecal samples, scALA generated 16 cSAGs of three specifically targeted bacterial species, Anaerostipes hadrus, Agathobacter rectalis, and Ruminococcus gnavus. A. hadrus cSAGs exhibited large, ten kbp-long, phage insertions, saccharide metabolic capacity, and frequent genomic recombination with related strains from cohabitant hosts. Noteworthy, cSAGs constructed using this method could expand bacterial genome databases and our understanding of within-species diversities in uncultured bacteria.

microbiology↗

Spatial transcriptomics reveals the two cancer stem cell-like populations in triple-negative breast cancer

Gene expression analysis at the single-cell level by next generation sequencing has revealed the existence of clonal dissemination and microheterogeneity in cancer metastasis. The current spatial analysis technologies can elucidate the heterogeneity of cell-cell interactions in situ. To reveal the regional and expressional heterogeneity in primary tumors and metastases, we performed transcriptomic analysis of microtissues dissected from a triple-negative breast cancer (TNBC) cell line MDA-MB-231 xenograft model with our automated tissue microdissection punching technology. This multiple-microtissue transcriptome analysis revealed three cancer cell-type clusters in the primary tumor and axillary lymph node metastasis, two of which were cancer stem cell (CSC)-like clusters (CD44/MYC-high, HMGA1-high). Reanalysis of public single-cell RNA-seq (scRNA-seq) datasets confirmed that the two CSC-like populations existed both in TNBC xenograft models and TNBC patients. In addition, the gene signature of the HMGA1-high CSC-like cluster has the potential to serve as a novel biomarker for diagnosis. The diversity of these multiple CSC-like populations may cause differential anticancer drug resistance, increasing the difficulty of curing this cancer.

cancer biology↗

Recovery of high-quality assembled genomes via single-cell genome-guided binning of metagenome assembly

BackgroundObtaining high-quality (HQ) reference genomes from microbial communities is crucial for understanding the phylogeny and function of uncultured microbes in complex microbial ecosystems. Despite the improved bioinformatic approaches to generate curated metagenome-assembled genomes (MAGs), existing metagenomic binners often fail to obtain reliable MAGs, and thus, they are nowhere comparable to genomes sequenced from isolates in terms of strain level resolution. Here, we present a single-cell genome-guided metagenome binning (MetaSAG) to reconstruct the strain-resolved genomes from microbial communities at once. ResultsMetaSAG employs single-cell amplified genomes (SAGs) generated with microfluidic technology as binning guides to recover improved draft genomes with the metagenomic data. To assess the performance of reconstructing genomes from various microbial communities, we compared MetaSAG with four conventional metagenomic binners using a cell mock community, human gut microbiota, and skin microbiota samples. MetaSAG showed precise contig binning and higher recovery rates (>97%) of rRNA and plasmids compared to conventional binners in genome reconstruction from the cell mock community. In human microbiota samples, MetaSAG recovered the largest number of genomes with a total of 103 gut microbial genomes (21 HQ and 65 showed >90% completeness) and 45 skin microbial genomes (10 HQ and 40 showed >90% completeness), respectively. Conventional binners recovered one Staphylococcus hominis genome, whereas MetaSAG recovered two S. hominis genomes from the identical skin microbiota sample. Single-cell sequencing indicated that these S. hominis genomes clearly derived from two distinct strains harboring specifically different plasmids. We found that all conventional S. hominis MAGs had substantial lack or excess of the genome sequences and contamination of other Staphylococcus bacteria (S. epidermidis). ConclusionsMetaSAG enabled us to obtain the strain-resolved genomes in the mock community and human microbiota samples by assigning metagenomic sequences correctly and covering both highly conserved genes such as rRNA genes and unique extrachromosomal elements, including plasmids. MetaSAG will provide HQ genomes that are difficult to obtain with metagenomic analyses alone and will facilitate the understanding of microbial ecosystems by elucidating detailed metabolic pathways and horizontal gene transfer networks through microbial genomes. MetaSAG is available at https://github.com/kojiari/metasag.

microbiology↗

Time-lapse single-cell transcriptomics reveals modulation of histone H3 for dormancy breaking

How quiescent cells break dormancy is a key issue in eukaryotic cells including cancer. Fungal spores, for example, remain quiescent for long periods until nourished, although the mechanisms by which dormancy is broken remain enigmatic. Transcriptome analysis could provide a clue, but methods to synchronously germinate large numbers of spores are lacking, and thus it remains a challenge to analyse gene expression upon germination. Hence, we developed methods to assemble transcriptomes from individual, asynchronous spore cells of fission yeast undergoing germination to assess transcriptomic changes over time. The virtual time-lapse analyses highlighted one of three copies of histone H3 genes for which transcription fluctuates during the initial stage of germination. Disruption of this temporal fluctuation caused defects in spore germination despite no visible defects in other stages of the life cycle. We conclude that modulation of histone H3 expression is a crucial wake-up trigger at dormancy breaking.

cell biology↗