Arabidopsis ECHIDNA protein is involved in seed coloration, protein trafficking to vacuoles, and vacuolar biogenesis

Flavonoids are a major group of plant-specific metabolites that determine flower and seed coloration. In plant cells, flavonoids are synthesized at the cytosolic surface of the endoplasmic reticulum and are sequestered in the vacuole. It is possible that membrane trafficking, including vesicle trafficking and organelle dynamics, contributes to flavonoid transport and accumulation. However, the underlying mechanism has yet to be fully elucidated. Here we show that the Arabidopsis ECHIDNA protein plays a role in flavonoid accumulation in the vacuole and protein trafficking to the vacuole. We found defective pigmentation patterns in echidna seed, possibly caused by reduced levels of proanthocyanidins, which determine seed coloration. The echidna mutant has defects in protein sorting to the protein storage vacuole as well as vacuole morphology. These findings indicate that ECHIDNA is involved in the vacuolar trafficking pathway as well as the previously described secretory pathway. In addition, we found a genetic interaction between echidna and green fluorescent seed 9 (gfs9), a membrane trafficking factor involved in flavonoid accumulation. Our findings suggest that vacuolar trafficking and/or vacuolar development, both of which are collectively regulated by ECHIDNA and GFS9, are required for flavonoid accumulation, resulting in seed coat pigmentation

Super responder of critical COVID-19 case

This report presents a case of a 74-year-old man who showed dramatic therapeutic response to treatment of coronavirus infectious disease-19 (COVID-19) pneumonia. He reported four-day history of sustained fever and acute progressive dyspnea. He developed severe respiratory failure, underwent urgent endotracheal intubation and showed marked elevation of inflammatory and coagulation markers such as c-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH) and D-dimer. Chest computed tomography (CT) demonstrated diffuse consolidation and ground glass opacity (GGO). We diagnosed critical COVID-19 pneumonia with detailed sick contact history and naso-pharyngeal swab of a reverse-transcriptase-polymerase-chain reaction (RT-PCR) assay testing. He received anti-viral drug, anti-interleukin (IL-6) receptor antagonist and intravenous methylprednisolone. After commencing combined intensive therapy, he showed dramatic improvement of clinical condition, serum biomarkers and radiological findings. Early diagnosis and rapid critical care management may provide meaningful clinical benefit even if severe case

Formation and Cycloreversion of 2-Silacyclobuta[2.3]cyclophanes via Photoinduced Electron Transfer

Irradiation of an acetonitrile solution containing dimethylbis(4-vinylphenylmethyl)silane 1a in the presence of 9,10-dicyanoanthracene leads to formation of the intramolecular photocycloadduct, 2-sila-cyclobuta[2.3]cyclophane (2a). In contrast, prolonged irradiation gave insoluble polymeric material. The photocycloreversion of 2a occurs efficiently (quantum yields exceeds unity) by use of redox-type photosensitization in the presence of magnesium perchlorate. The transient absorption spectra generated by pulse radiolysis and gamma-radiolysis show that the radical cation species generated from 1a is different from that arising from 2a

The Effect of Interim FDG-PET-guided Response-Adapted Therapy in Pediatric Patients with Hodgkin’s Lymphoma (HL-14) : Protocol for a Phase II Study

This trial enrolls patients with untreated Hodgkin’s lymphoma aged<20 years at diagnosis and examines the effects of omitting radiation therapy if the FDG-positron emission tomography (PET) findings after two completed cycles of combination chemotherapy are negative. It thereby aims to determine whether patients who truly require radiation therapy can be identified by FDG-PET. If so, this modality could be used to omit radiation therapy for all other patients, decreasing the risk of serious long-term complications without affecting survival rates. The outcomes of patients for whom FDG-PET is used to assess early treatment response will also be determined

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection