Nitrogen Fixation and Translocation in Sugarcane

World sugarcane production is increasing rapidly as a biofuel. In some areas in Brazil, sugarcane has been grown continually over very long periods without N fertiliser inputs. Therefore, the occurrence of N fixation has been suspected. However, quantitative studies seeking to identify the N~2~ fixation sites in the plant and to record the translocation of fixed N around the plant have not yet established. A ^15^N~2~ gas tracer experiment was conducted using young sugarcane plants to investigate the sites of N~2~ fixation and also to explore the possibility of translocation of the fixed N among the plant's major organs. Young sugarcane plants (_Saccharum officinarum_ L.) about 40 cm high and some 14 days after sprouting from a stem cutting were exposed to ^15^N~2~ labeled air in a 500 mL plastic cylinder for 7 days. Following the 7-day ^15^N~2~ feeding, some plants were potted and grown on in normal air for a further chase period. The incorporation of ^15^N into the shoot, roots, and stem cutting was analysed at day-3, and day-7 of the labeling period and at day-14, and day-21 during the chase period. After 3 days of ^15^N~2~ feeding, the % of N derived from the ^15^N labeled air in the shoot, roots and stem cutting were 0.027%, 2.22% and 0.271%, respectively. The roots showed the highest N fixing activity followed by the stem cutting, while the incorporation of ^15^N into the shoot was very low. After 21 days about a half of the N originating in the stem cutting had been transported to the shoot and the roots. However, the ^15^N fixed either in the roots or in the stem cutting remained in the original parts and was not appreciably transported to the shoot

THE EFFECTS OF LIFTING THE ROTATIONAL AXIS ON SWING SPEED OF THE INSTEP

This study was conducted to investigate the hypothesis that expert soccer players lifted the trochanter major rotational axis of the swing leg faster before impact to increase the speed of the swing leg. This movement pattern is referred to as "lifting the rotational axis of the swing leg". To examine this hypothesis, an experiment and computer simulation was carried out. The results were as follows: (1) Experts were found to lift the rotational axis of the swing leg to a greater degree than novices. (2) Computer simulations of the swing leg, developed by combining data of torque patterns data of the thigh and the leg from the novices with kinematic data of the trochanter major from the expert group, resulted in a slight increase in swing speed. When the kinematic data from the most accomplished expert alone was used, a remarkable increase in swing speed was seen. These results suggest the movement pattern such as lifting the rotational axis of the swing leg was useful in increasing the swing speed

An Active C-Terminally Truncated Form of Ca2+/Calmodulin-Dependent Protein Kinase Phosphatase-N (CaMKP-N/PPM1E)

Ca2+/calmodulin-dependent protein kinase phosphatase (CaMKP/PPM1F) and its nuclear homolog CaMKP-N (PPM1E) are Ser/Thr protein phosphatases that belong to the PPM family. CaMKP-N is expressed in the brain and undergoes proteolytic processing to yield a C-terminally truncated form. The physiological significance of this processing, however, is not fully understood. Using a wheat-embryo cell-free protein expression system, we prepared human CaMKP-N (hCaMKP-N(WT)) and the truncated form, hCaMKP-N(1–559), to compare their enzymatic properties using a phosphopeptide substrate. The hCaMKP-N(1–559) exhibited a much higher value than the hCaMKP-N(WT) did, suggesting that the processing may be a regulatory mechanism to generate a more active species. The active form, hCaMKP-N(1–559), showed Mn2+ or Mg2+-dependent phosphatase activity with a strong preference for phospho-Thr residues and was severely inhibited by NaF, but not by okadaic acid, calyculin A, or 1-amino-8-naphthol-2,4-disulfonic acid, a specific inhibitor of CaMKP. It could bind to postsynaptic density and dephosphorylate the autophosphorylated Ca2+/calmodulin-dependent protein kinase II. Furthermore, it was inactivated by H2O2 treatment, and the inactivation was completely reversed by treatment with DTT, implying that this process is reversibly regulated by oxidation/reduction. The truncated CaMKP-N may play an important physiological role in neuronal cells.This work was supported, in part, by Grants-in-Aid for Scientific Research (21590334) from the Ministry of Education, Science, Sports, and Culture of Japan and by a grant from the Japan Foundation for Applied Enzymology

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

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