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Matsui, H.

Publications and source records attributed to Matsui, H..

At least 37 records · Page 2Linked to original sources

Genetic and phosphoproteomic basis of LysM-mediated immune signaling in Marchantia polymorpha highlights conserved elements and new aspect of pattern-triggered immunity in land plants

Pattern-recognition receptor (PRR)-triggered immunity (PTI) wards off a wide range of pathogenic microbes, playing a pivotal role in plant immunity. The model liverwort Marchantia polymorpha is emerging as a popular model for investigating the evolution of plant-microbe interactions. M. polymorpha triggers defense-related gene expression upon sensing components of bacterial and fungal extracts, suggesting the existence of PTI in this plant model. However, the molecular components of the putative PTI in M. polymorpha have not yet been described. We show that, in M. polymorpha, which has four LysM receptor homologs, lysin motif (LysM) receptor-like kinase (LYK) MpLYK1 and LYK-related (LYR) MpLYR are required for sensing chitin and peptidoglycan fragments, triggering a series of characteristic immune responses. Comprehensive phosphoproteomic analysis of M. polymorpha in response to chitin treatment identified regulatory proteins that potentially shape LysM-mediated PTI. The identified proteins included homologs of well-described PTI components in angiosperms as well as proteins whose roles in PTI are not yet determined, including the blue-light receptor phototropin MpPHOT. We revealed that MpPHOT is required for a negative feedback of defense-related gene expression during PTI. Taken together, this study outlines the basic framework of LysM-mediated PTI in M. polymorpha and demonstrates the utility of M. polymorpha as a plant model for discovering novel or fundamental molecular mechanisms underlying PRR-triggered immune signaling in plants.

plant biology↗

Cleavage of the Jaw1 C-terminal region enhances its augmentative effect on the Ca2+ release via inositol 1,4,5-trisphosphate receptors

Jaw1, a tail-anchored protein with 39 carboxyl (C)-terminal amino acids, is oriented to the lumen of the endoplasmic reticulum and outer nuclear membrane. We previously reported that Jaw1, as a member of the KASH protein family, plays a role in maintaining nuclear shape via its C-terminal region. Furthermore, we recently reported that Jaw1 functions as an augmentative effector of Ca2+ release from the endoplasmic reticulum by interacting with the inositol 1,4,5-trisphosphate receptors (IP3Rs). Intriguingly, the C-terminal region is partially cleaved, meaning that Jaw1 exists in the cell in at least two forms: uncleaved and cleaved. However, the mechanism of the cleavage event and its physiological significance remain to be determined. In this study, we demonstrate that the C-terminal region of Jaw1 is cleaved after its insertion by the signal peptidase complex (SPC). Particularly, our results indicate that the SPC with the catalytic subunit SEC11A, but not SEC11C, specifically cleaves Jaw1. Furthermore, using a mutant with a deficit in the cleavage event, we demonstrate that the cleavage event enhances the augmentative effect of Jaw1 on the Ca2+ release ability of IP3Rs. Summary statementThe C-terminal region of Jaw1, a tail-anchored protein, is cleaved by signal peptidase complex and this cleavage event enhances the augmentative effect of Jaw1 on the Ca2+ release activity of inositol 1,4,5-trisphosphate receptors

cell biology↗

Characterization of HcaA, a novel autotransporter protein in Helicobacter cinaedi, and its role in host cell adhesion

Helicobacter cinaedi infects the human gut and causes invasive infections such as bacteremia and cellulitis through bacterial translocation. However, the mechanism by which H. cinaedi attaches to host cells and establishes infection remains unclear. This study aimed to investigate the relationship between a novel putative autotransporter protein, H. cinaedi autotransporter protein A (HcaA), and its role in pathogenicity. The cytotoxicity of H. cinaedi infection in colon epithelial cell lines (Caco-2 and HT-29) was assessed using a lactate dehydrogenase assay, and it was found that cytotoxicity significantly decreased upon HcaA knockout. Adhesion assays further revealed that the HcaA-knockout strain showed significantly reduced attachment to the human epithelial colorectal adenocarcinoma cell line (Caco-2) compared to that of the wild-type strain. Moreover, the recombinant HcaA protein demonstrated strong adhesion properties to the human monocytic cell line (U937). The adhesive activity was diminished when the RGD motif in HcaA was replaced with RAD, indicating that the RGD motif in HcaA is crucial for host cell adhesion. To determine the role of HcaA in H. cinaedi infection in vivo, C57BL/6 mice were orally infected with wild-type and HcaA-knockout H. cinaedi strains. Bacterial colonization was assessed 7, 14, and 28 days post-infection. At 7 days post-infection, colonization was significantly lower in mice infected with the HcaA-knockout strain compared to those infected with the wild-type strain. In conclusion, our findings suggest that HcaA, a novel putative autotransporter protein in H. cinaedi, plays a significant role as an adhesin in establishing colonization. IMPORTANCEHelicobacter species are classified as gastric or enterohepatic according to their habitat. Among enterohepatic Helicobacter species, which inhabit the intestine, colon and liver, H. cinaedi has been most frequently isolated from humans. H. cinaedi often causes bacteremia and cellulitis in immunocompromised hosts. Here, we focused on the H. cinaedi autotransporter protein A (HcaA), a novel virulence factor in H. cinaedi. We discovered that HcaA contributes to cell adhesion via its RGD motif. Furthermore, in animal experiments, bacterial colonization was reduced in mice infected with HcaA-knockout strains, supporting the hypothesis that HcaA contributes to H. cinaedi adhesion to host cells. Our study provides a novel mechanism for the establishment of H. cinaedi infections and provides new insights into the role of autotransporter proteins in the establishment of Helicobacter infection.

microbiology↗

Robust capability of renal tubule fatty acid uptake from apical and basolateral membranes in physiology and disease

Excess lipid accumulation is associated with obesity-related chronic kidney disease, but the mechanisms of fatty acid (FA) uptake have been poorly understood. To this end, we investigated how FAs are taken up by tubular epithelial cells (TECs) in mice by using in vivo FA tracing and histological methods. Immunohistochemistry showed that CD36, which is a well-known FA transporter, was abundantly expressed on the basolateral side of proximal TECs (PTECs). The uptake of 125I-BMIPP (a radiolabeled FA tracer) was significantly reduced in CD36-knockout kidneys at 1 min after injection. In vivo imaging with multiphoton microscopy revealed that BODIPY-C12 (a fluorescence-labeled FA tracer) accumulated on both the basolateral and apical sides of PTECs. Numerous lipid droplets accumulated in PTECs after accelerated lipolysis. Furthermore, PTEC-specific injury via diphtheria toxin (DT) injection in transgenic mice expressing the DT receptor resulted in a compensatory increase in lipid accumulation in downstream TECs. Importantly, urinary FAs were undetectable, even in mice and humans with remarkable albuminuria. Our data demonstrate that renal TECs take up FAs from blood (CD36-dependent) and primary urine (CD36-independent) and can store excess FAs as neutral lipids. The results further show that renal tubules have hitherto largely unappreciated mechanisms by which the excretion of FAs into the urine is avoided.

biochemistry↗

Regulatory variants active in iPSC-derived pancreatic progenitor cells are associated with Type 2 Diabetes in adults

Pancreatic progenitor cells (PPC) are an early developmental multipotent cell type that give rise to mature endocrine, exocrine, and ductal cells. To investigate the extent to which regulatory variants active in PPC contribute to pancreatic complex traits and disease in the adult, we derived PPC from induced pluripotent stem cells (iPSCs) of nine unrelated individuals and generated single cell profiles of chromatin accessibility (snATAC- seq) and transcriptome (scRNA-seq). While iPSC-PPC differentiation was asynchronous and included cell types from early to late developmental stages, we found that the predominant cell type consisted of NKX6-1+ progenitors. Genetic characterization using snATAC-seq identified 86,261 regulatory variants that either displayed chromatin allelic bias and/or were predicted to affect active transcription factor (TF) binding sites. Integration of these regulatory variants with 380 fine-mapped type 2 diabetes (T2D) risk loci identified regulatory variants in 209 of these loci that are functional in iPSC-PPC, either by affecting transcription factor binding or through association with allelic effects on chromatin accessibility. The PPC active regulatory variants in 65 of these loci showed strong evidence of causally underlying the association with T2D. Our study shows that studying the functional associations of regulatory variation in iPSC-PPC enables the identification and characterization of causal SNPs for adult Type 2 Diabetes.

genetics↗

Fine mapping spatiotemporal mechanisms of genetic variants underlying cardiac traits and disease

The causal variants and genes underlying thousands of cardiac GWAS signals have yet to be identified. Here, we leveraged spatiotemporal information on 966 RNA-seq cardiac samples and performed an expression quantitative trait locus (eQTL) analysis detecting eQTLs considering both eGenes and eIsoforms. We identified 2,578 eQTLs associated with a specific developmental stage-, tissue- and/or cell type. Colocalization between eQTL and GWAS signals of five cardiac traits identified variants with high posterior probabilities for being causal in 210 GWAS loci. Pulse pressure GWAS loci were enriched for colocalization with fetal- and smooth muscle- eQTLs; pulse rate with adult- and cardiac muscle- eQTLs; and atrial fibrillation with cardiac muscle- eQTLs. Fine mapping identified 79 credible sets with five or fewer SNPs, of which 15 were associated with spatiotemporal eQTLs. Our study shows that many cardiac GWAS variants impact traits and disease in a developmental stage-, tissue- and/or cell type-specific fashion.

genetics↗

In heart failure reactivation of RNA-binding proteins drives the transcriptome into a fetal state

Transcriptome-wide expression changes occur during heart failure, including reactivation of fetal-specific isoforms. However, the underlying molecular mechanisms and the extent to which a fetal gene program switch occurs remains unclear. Limitations hindering transcriptome-wide analyses of alternative splicing differences (i.e. isoform switching) in cardiovascular system (CVS) tissues between fetal and adult (healthy and diseased) stages have included both cellular heterogeneity across bulk RNA-seq samples and limited availability of fetal tissue for research. To overcome these limitations, we have deconvoluted the cellular compositions of 996 RNA-seq samples representing heart failure, healthy adult (heart and arteria), and fetal-like (iPSC-derived cardiovascular progenitor cells) CVS tissues. Comparison of the expression profiles revealed that RNA-binding proteins (RBPs) are highly overexpressed in fetal-like compared with healthy adult and are reactivated in heart failure, which results in expression of thousands fetal-specific isoforms. Of note, isoforms for 20 different RBPs were among those that reverted in heart failure to the fetal-like expression pattern. We determined that, compared with adult-specific isoforms, fetal-specific isoforms are more likely to bind RBPs, have canonical sequences at their splice sites and encode proteins with more functions. Our findings suggest targeting RBP fetal-specific isoforms could result in novel therapeutics for heart failure.

genomics↗

iPSC-derived pancreatic progenitors are an optimal model system to study T2D regulatory variants active during fetal development of the pancreas

The impact of genetic regulatory variation active in early pancreatic development on adult pancreatic disease and traits is not well understood. Here, we generate a panel of 107 fetal-like iPSC-derived pancreatic progenitor cells (iPSC-PPCs) from whole genome-sequenced individuals and identify 4,065 genes and 4,016 isoforms whose expression and/or alternative splicing are affected by regulatory variation. We integrate eQTLs identified in adult islets and whole pancreas samples, which reveal 1,805 eQTL associations that are unique to the fetal-like iPSC-PPCs and 1,043 eQTLs that exhibit regulatory plasticity across the fetal-like and adult pancreas tissues. Colocalization with GWAS risk loci for pancreatic diseases and traits show that some putative causal regulatory variants are active only in the fetal-like iPSC-PPCs and likely influence disease by modulating expression of disease-associated genes in early development, while others with regulatory plasticity likely exert their effects in both the fetal and adult pancreas by modulating expression of different disease genes in the two developmental stages.

genomics↗

Transport engineering for improving production and secretion of valuable alkaloids in Escherichia coli

Metabolic engineering of microorganisms to produce specialized plant metabolites has been established. However, these methods are limited by low productivity and the intracellular accumulation of metabolites. Here, we aimed to use transport engineering for producing reticuline, an important intermediate in the alkaloid biosynthetic pathway. We established a reticuline-producing Escherichia coli strain and introduced a multidrug and toxic compound extrusion transporter, Arabidopsis AtDTX1, into it. AtDTX1 was selected due to its suitable expression in E. coli and its reticuline-transport activity. Expression of AtDTX1 significantly enhanced reticuline production by 11-fold; produced reticuline was secreted into the medium. AtDTX1 expression conferred high plasmid stability, and up- or downregulated genes associated with biological processes including metabolic pathways for reticuline biosynthesis, leading to a high production and secretion of reticuline. The successful application of a transporter for alkaloid production suggests that the transport engineering approach may improve the biosynthesis of specialized metabolites via metabolic engineering.

synthetic biology↗

HBO1-MLL interaction promotes AF4/ENL/P-TEFb-mediated leukemogenesis

Leukemic oncoproteins cause uncontrolled self-renewal of hematopoietic progenitors by aberrant gene activation, eventually causing leukemia. However, the molecular mechanism of aberrant gene activation remains elusive. Here, we showed that leukemic MLL fusion proteins associate with the HBO1 histone acetyltransferase (HAT) complex through their TRX2 domain. Among many MLL fusions, MLL-ELL particularly depended on its association with the HBO1 complex for leukemic transformation. The C-terminal portion of ELL provided a binding platform for multiple factors including AF4, EAF1 and p53. MLL-ELL activated gene expression by loading an AF4 /ENL/P-TEFb complex (AEP) onto the target promoters. The HBO1 complex promoted the use of AEP over EAF1 and p53. Moreover, the NUP98-HBO1 fusion protein exerted its oncogenic properties via interaction with MLL but not its intrinsic HAT activity. Thus, the interaction between HBO1 and MLL is an important nexus in leukemic transformation, which may serve as a therapeutic target for drug development.

cancer biology↗

HOXA9 promotes MYC-mediated leukemogenesis by maintaining gene expression for multiple anti-apoptotic pathways

HOXA9 is often highly expressed in leukemias. However, its precise roles in leukemogenesis remain elusive. Here, we show that HOXA9 maintains gene expression for multiple anti-apoptotic pathways to promote leukemogenesis. In MLL-rearranged leukemia, MLL fusion directly activates the expression of MYC and HOXA9. Combined expression of MYC and HOXA9 induced leukemia, whereas single gene transduction of either did not, indicating a synergy between MYC and HOXA9. HOXA9 sustained expression of the genes implicated to the hematopoietic precursor identity when expressed in hematopoietic precursors, but did not reactivate it once silenced. Among the HOXA9 target genes, BCL2 and SOX4 synergistically induced leukemia with MYC. Not only BCL2, but also SOX4 suppressed apoptosis, indicating that multiple anti-apoptotic pathways underlie cooperative leukemogenesis by HOXA9 and MYC. These results demonstrate that HOXA9 is a key transcriptional maintenance factor which promotes MYC-mediated leukemogenesis, potentially explaining why HOXA9 is highly expressed in many leukemias.

cancer biology↗

Interceptive capturing in large-billed crows: Velocity-dependent weighing of prediction of future target location and visual feedback of current target location.

Interception of a moving target is a fundamental behaviour of predators and requires tight coupling between the sensory and motor systems. In the literature of foraging studies, feedback mechanisms based on current target position are frequently reported. However, there have also been recent reports of animals employing feedforward mechanisms, in which prediction of future target location plays an important role. In nature, coordination of these two mechanisms may contribute to intercepting evasive prey. However, how animals weigh these two mechanisms remain poorly understood. Here, we conducted a behavioural experiment involving crows (which show flexible sensorimotor coordination in various domains) capturing a moving target. We changed the velocity of the target to examine how the crows utilised prediction of the target location. The analysis of moment-to-moment head movements and computational simulations revealed that the crows used prediction of future target location when the target velocity was high. In contrast, their interception depended on the current momentary position of the target when the target velocity was slow. These results suggest that crows successfully intercept targets by weighing predictive and visual feedback mechanisms, depending on the target velocity.

animal behavior and cognition↗

APOBEC3B reporter myeloma cell lines identify DNA damage response pathways leading to APOBEC3B expression

Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) DNA cytosine deaminase 3B (A3B) is a DNA editing enzyme which induces genomic DNA mutations in multiple myeloma and various other cancers. APOBEC family proteins are highly homologous so it is especially difficult to investigate the biology of A3B alone in cancer cells. To investigate A3B function in myeloma cells easily and comprehensively, we used CRISPR/Cas9 to generate A3B reporter cells that contain 3xFLAG tag and IRES-EGFP sequences integrated at the end of the A3B gene. These reporter cells stably express 3xFLAG tagged A3B and the reporter EGFP and this expression is enhanced under known stimuli, such as PMA. Conversely, shRNA knockdown of A3B decreased EGFP fluorescence and 3xFLAG tagged A3B protein levels. We screened a series of anticancer treatments using these cell lines and identified that most conventional therapies, such as antimetabolites or radiation, exacerbated endogenous A3B expression, but recent molecular targeting drugs, including bortezomib, lenalidomide and elotuzumab, did not. Furthermore, chemical inhibition of ATM, ATR and DNA-PK suppressed the EGFP expression upon treatment with antimetabolites. These results suggest that DNA damage response triggers A3B expression through ATM, ATR and DNA-PK signaling.

cancer biology↗

Structural variant classes and short tandem repeats differentially impact gene expression and complex traits

Structural variants (SVs) and short tandem repeats (STRs) comprise a broad group of diverse DNA variants which vastly differ in their sizes and distributions across the genome. Here, we show that different SV classes and STRs differentially impact gene expression and complex traits. Functional differences between SV classes and STRs include their genomic locations relative to eGenes, likelihood of being associated with multiple eGenes, associated eGene types (e.g., coding, noncoding, level of evolutionary constraint), effect sizes, linkage disequilibrium with tagging single nucleotide variants used in GWAS, and likelihood of being associated with GWAS traits. We also identified a set of high-impact SVs/STRs associated with the expression of three or more eGenes via chromatin loops and showed they are highly enriched for being associated with GWAS traits. Our study provides insights into the genomic properties of structural variant classes and short tandem repeats that impact gene expression and human traits.

genomics↗

Discovery and Quality Analysis of a Comprehensive Set of Structural Variants and Short Tandem Repeats using Deep Whole Genome Sequencing Data

Structural variants (SVs) and short tandem repeats (STRs) are important sources of genetic diversity but are not routinely analyzed in genetic studies because they are difficult to accurately identify and genotype. Because SVs and STRs range in size and type, it is necessary to apply multiple algorithms that incorporate different types of evidence from sequencing data and employ complex filtering strategies to discover a comprehensive set of high-quality and reproducible variants. Here we assembled a set of 719 deep whole genome sequencing (WGS) samples (mean 42x) from 477 distinct individuals which we used to discover and genotype a wide spectrum of SV and STR variants using five algorithms. We used 177 unique pairs of genetic replicates to identify factors that affect variant call reproducibility and developed a systematic filtering strategy to create of one of the most complete and well characterized maps of SVs and STRs to date.

genomics↗

Estimation of the Hemoglobin Glycation Rate Constant

AimIn a previous study, a method of obtaining mean erythrocyte age (MRBC) from HbA1c and average plasma glucose (AG) was proposed. However, the true value of the hemoglobin glycation constant (kg dL/mg/day), required for this model has yet to be well characterized. Another study also proposed a method of deriving MRBC from erythrocyte creatine (EC). Utilizing these formulae, this study aimed to determine a more accurate estimate of kg.\n\nMethods107 subjects including 31 patients with hemolytic anemia and 76 subjects without anemia were included in this study. EC and HbA1c data were analyzed, and MRBC using HbA1c, AG and the newly-derived constant, kg were compared to MRBC using traditional 51Cr in three patients whose data were taken from previous case studies.\n\nResultA value of 7.0 x 10-6 dL/mg/day was determined for kg. MRBC using HbA1c, AG and kg were found to no be significantly different (paired t-test, p = 0.45) to MRBC using traditional 51Cr.\n\nConclusionskg enables the estimation of MRBC from HbA1c and AG.

physiology↗

Human iPSC gene signatures and X chromosome dosage impact response to WNT inhibition and cardiac differentiation fate

Non-genetic variability in human induced pluripotent stem cell (iPSC) lines impacts their differentiation outcome, limiting their utility for genetic studies and clinical applications. Despite the importance of understanding how non-genetic molecular variability influences iPSC differentiation outcome, large-scale studies capable of addressing this question have not yet been conducted. Here, we performed 258 directed differentiations of 191 iPSC lines using established protocols to generate iPSC-derived cardiovascular progenitor cells (iPSC-CVPCs). We observed cellular heterogeneity across the iPSC-CVPC samples due to varying fractions of two cell types: cardiomyocytes (CMs) and epicardium-derived cells (EPDCs). Analyzing the transcriptomes of CM-fated and EPDC-fated iPSCs discovered that 91 signature genes and X chromosome dosage differences influence WNT inhibition response during differentiation and are associated with cardiac fate. Analysis of an independent set of 39 iPSCs differentiated to the cardiac lineage confirmed shared sex and transcriptional differences that impact cardiac fate outcome. The scale and systematic approach of our study enabled novel insights into how iPSC transcriptional and X chromosome gene dosage differences influence WNT signaling during differentiation and hence cardiac cell fate.

genomics↗

Chromatin co-accessibility is highly structured, spans entire chromosomes, and mediates long range regulatory genetic effects

Chromatin accessibility identifies active regions of the genome, often at transcription factor (TF) binding sites, enhancers, and promoters, and contains regulatory genetic variation. Functionally related accessible sites have been reported to be co-accessible; however, the prevalence and range of co-accessibility is unknown. We perform ATAC-seq in induced pluripotent stem cells from 134 individuals and integrate it with RNA-seq, WGS, and ChIP-seq, providing the first long-range chromosome-length analysis of co-accessibility. We show that co-accessibility is highly connected, with sites having a median of 24 co-accessible partners up to 250Mb away. We also show that co-accessibility can de novo identify known and novel co-expressed genes, and co-regulatory TFs and chromatin states. We perform a cis and trans-caQTL, a trans-eQTL, and examine allelic effects of co-accessibility, identifying tens of thousands of trans-caQTLs, and showing that trans genetic effects can be propagated through co-accessibility to gene expression for cell-type and disease relevant genes.

genomics↗