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Hosoya, T.

Publications and source records attributed to Hosoya, T..

3 recordsLinked to original sources

BAP1 deubiquitinase is a potent repressor of fetal hemoglobin biosynthesis

Human globin gene production transcriptionally \"switches\" from fetal to adult synthesis shortly after birth, and is controlled by macromolecular complexes that enhance or suppress transcription by cis-elements scattered throughout the locus. The DRED repressor is recruited to the {varepsilon}- and {gamma}-globin promoters by the orphan nuclear receptors TR2 (NR2C1) and TR4 (NR2C2) to engender their silencing in adult erythroid cells. Here we found that nuclear receptor corepressor-1 (NCoR1) is a critical component of DRED that acts as a scaffold to unite the DNA binding and epigenetic enzyme components (e.g. DNMT1 and LSD1) that elicit DRED function. We also describe a potent new regulator of {gamma}-globin repression: the deubiquitinase BAP1 is a component of the repressor complex whose activity maintains NCoR1 at sites in the {beta}-globin locus, and BAP1 inhibition in erythroid cells massively induces {gamma}-globin synthesis. These data provide new mechanistic insights through the discovery of novel epigenetic enzymes that mediate {gamma}-globin gene repression.

developmental biology

High throughput single cell sequencing of both T-cell-receptor-beta alleles

Allelic exclusion is a vital mechanism for the generation of monospecificity to foreign antigens in B- and T-lymphocytes. Here we developed a high-throughput barcoded method to simultaneously analyze the VDJ recombination status of both mouse T cell receptor beta alleles in hundreds of single cells using Next Generation Sequencing.

immunology

The ash dieback invasion of Europe was founded by two individuals from a native population with huge adaptive potential

Accelerating international trade and climate change make pathogen spread an increasing concern. Hymenoscyphus fraxineus, the causal agent of ash dieback is one such pathogen, moving across continents and hosts from Asian to European ash. Most European common ash (Fraxinus excelsior) trees are highly susceptible to H. fraxineus although a small minority (~5%) evidently have partial resistance to dieback. We have assembled and annotated a draft of the H. fraxineus genome which approaches chromosome scale. Pathogen genetic diversity across Europe, and in Japan, reveals a tight bottleneck into Europe, though a signal of adaptive diversity remains in key host interaction genes (effectors). We find that the European population was founded by two divergent haploid individuals. Divergence between these haplotypes represents the 'shadow' of a large source population and subsequent introduction would greatly increase adaptive potential and the pathogen's threat. Thus, EU wide biological security measures remain an important part of the strategy to manage this disease.

genomics