The double-stranded break-forming activity of plant SPO11s and a novel rice SPO11 revealed by a Drosophila bioassay

<p>Abstract</p> <p>Background</p> <p>SPO11 is a key protein for promoting meiotic recombination, by generating chromatin locus- and timing-specific DNA double-strand breaks (DSBs). The DSB activity of SPO11 was shown by genetic analyses, but whether SPO11 exerts DSB-forming activity by itself is still an unanswered question. DSB formation by SPO11 has not been detected by biochemical means, probably because of a lack of proper protein-folding, posttranslational modifications, and/or specific SPO11-interacting proteins required for this activity. In addition, plants have multiple SPO11-homologues.</p> <p>Results</p> <p>To determine whether SPO11 can cleave DNA by itself, and to identify which plant SPO11 homologue cleaves DNA, we developed a <it>Drosophila </it>bioassay system that detects the DSB signals generated by a plant SPO11 homologue expressed ectopically. We cytologically and genetically demonstrated the DSB activities of <it>Arabidopsis </it>AtSPO11-1 and AtSPO11-2, which are required for meiosis, in the absence of other plant proteins. Using this bioassay, we further found that a novel SPO11-homologue, OsSPO11D, which has no counterpart in <it>Arabidopsis</it>, displays prominent DSB-forming activity. Quantitative analyses of the rice SPO11 transcripts revealed the specific increase in OsSPO11D mRNA in the anthers containing meiotic pollen mother cells.</p> <p>Conclusions</p> <p>The <it>Drosophila </it>bioassay system successfully demonstrated that some plant SPO11 orthologues have intrinsic DSB activities. Furthermore, we identified a novel SPO11 homologue, OsSPO11D, with robust DSB activity and a possible meiotic function.</p

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

C3ガタ ホスホエノールピルビンサン カルボキシラーゼ イデンシ ノ ハツゲン チョウセツ キコウ ノ カイセキ

京都大学0048新制・課程博士博士(農学)甲第9781号農博第1293号新制||農||852(附属図書館)学位論文||H14||N3712(農学部図書室)UT51-2002-M159京都大学大学院農学研究科応用生命科学専攻(主査)教授 佐藤 文彦, 教授 關谷 次郎, 教授 泉井 桂学位規則第4条第1項該当Doctor of Agricultural ScienceKyoto UniversityDA

Evolution of Proliferative Model Protocells Highly Responsive to the Environment

In this review, we discuss various methods of reproducing life dynamics using a constructive approach. An increase in the structural complexity of a model protocell is accompanied by an increase in the stage of reproduction of a compartment (giant vesicle; GV) from simple reproduction to linked reproduction with the replication of information molecules (DNA), and eventually to recursive proliferation of a model protocell. An encounter between a plural protic catalyst (C) and DNA within a GV membrane containing a plural cationic lipid (V) spontaneously forms a supramolecular catalyst (C@DNA) that catalyzes the production of cationic membrane lipid V. The local formation of V causes budding deformation of the GV and equivolume divisions. The length of the DNA strand influences the frequency of proliferation, associated with the emergence of a primitive information flow that induces phenotypic plasticity in response to environmental conditions. A predominant protocell appears from the competitive proliferation of protocells containing DNA with different strand lengths, leading to an evolvable model protocell. Recently, peptides of amino acid thioesters have been used to construct peptide droplets through liquid–liquid phase separation. These droplets grew, owing to the supply of nutrients, and were divided repeatedly under a physical stimulus. This proposed chemical system demonstrates a new perspective of the origins of membraneless protocells, i.e., the “droplet world” hypothesis. Proliferative model protocells can be regarded as autonomous supramolecular machines. This concept of this review may open new horizons of “evolution” for intelligent supramolecular machines and robotics

Physicochemical Cause and Effect Observed in DNA Length-Dependent Division of Protocell as the Primitive Flow of Information

In the prebiotic era, physicochemical cause and effect served as the primitive flow of information for protocells. Our recent study claimed that the manners and frequencies of self-reproduction of giant vesicle (GV) -based model protocells were regulated by the incorporated DNA-length, and not the base-pair sequence due to the presence of a supramolecular catalyst (lipo-deoxyribozyme) composed of DNA and lipophilic catalysts. The DNA-length dependent dynamics of the self-reproducing GVs containing different length of DNA were examined by three independent experiments; Population analysis by flow cytometric measurements, counting of　increased numbers of protocells and direct morphological observation of a single GV by confocal microscopy. These results may shed light on the information system in the prebiotic stage, when the central dogma was not established. Notably, recent reports have revealed the possible influence of DNA length on the activation of living cells through the complexation of DNA to an enzyme in non-sequential aggregation manner.This work was supported by JSPS KAKENHI (Grant Numbers JP25103009, JP16K05759 and JP17H04876), ‘Platform for Dynamic Approaches to Living System’ at the University of Tokyo, Kanagawa University Grant for Joint Research, and the Yoshida Scholarship Foundation

Computed tomography findings of paranasal sinuses in patients with eosinophilic granulomatosis with polyangiitis: Comparison with other eosinophilic sinus diseases and clinical relevance of their severity

Background: Although paranasal sinuses are one of the most representative organs affected by eosinophilic granulomatosis with polyangiitis (EGPA), they have not been studied sufficiently. The aim of this study was to compare computed tomography (CT) findings in paranasal sinuses of EGPA with those of other eosinophilic sinus diseases and elucidate the clinical relevance of their severity. Methods: CT findings of paranasal sinuses in EGPA patients prior to therapeutic intervention (n = 30) were evaluated using the Lund–Mackay staging (LMS) system and compared with those of three control diseases [(NSAID-exacerbated respiratory disease (N-ERD), aspirin-tolerant asthma, and eosinophilic chronic rhinosinusitis without asthma (ECRS)]. We divided EGPA patients into three groups based on their LMS scores and examined their association with disease manifestation. Results: Total scores of the LMS system in EGPA were significantly lower than those of N-ERD and ECRS without asthma. There was a large variation in total LMS scores in EGPA, suggesting considerable heterogeneity of their sinus lesions. Although EGPA with low LMS system scores showed only minor findings in maxillary and anterior ethmoid regions, those with high LMS system scores were characterized by high scores in the ostiomeatal complex. However, the frequencies of patients with a Five-Factor Score ≥2 and with cardiac involvement were significantly higher for EGPA with low LMS system scores. Conclusions: Although paranasal sinus lesions in EGPA were less severe than those of other eosinophilic sinus diseases, their milder CT findings may be associated with a higher frequency of extra-respiratory organ involvement