Symmetrically dimethylated histone H3R2 promotes global transcription during minor zygotic genome activation in mouse pronuclei

受精卵の発生に重要な因子を発見 --ヒストンのアルギニンジメチル化が重要--. 京都大学プレスリリース. 2021-05-13.Paternal genome reprogramming, such as protamine–histone exchange and global DNA demethylation, is crucial for the development of fertilised embryos. Previously, our study showed that one of histone arginine methylation, asymmetrically dimethylated histone H3R17 (H3R17me2a), is necessary for epigenetic reprogramming in the mouse paternal genome. However, roles of histone arginine methylation in reprogramming after fertilisation are still poorly understood. Here, we report that H3R2me2s promotes global transcription at the 1-cell stage, referred to as minor zygotic genome activation (ZGA). The inhibition of H3R2me2s by expressing a histone H3.3 mutant H3.3R2A prevented embryonic development from the 2-cell to 4-cell stages and significantly reduced global RNA synthesis and RNA polymerase II (Pol II) activity. Consistent with this result, the expression levels of MuERV-L as minor ZGA transcripts were decreased by forced expression of H3.3R2A. Furthermore, treatment with an inhibitor and co-injection of siRNA to PRMT5 and PRMT7 also resulted in the attenuation of transcriptional activities with reduction of H3R2me2s in the pronuclei of zygotes. Interestingly, impairment of H3K4 methylation by expression of H3.3K4M resulted in a decrease of H3R2me2s in male pronuclei. Our findings suggest that H3R2me2s together with H3K4 methylation is involved in global transcription during minor ZGA in mice

Altered Metabolism in Lactose-negative Mutants of Lactobacillus casei by Conjugation

ラクトース非発酵性Lactobacillus caseiはラクトース発酵能を欠くために,牛乳培地では酸生成がみられず,乳業用乳酸菌として応用する場合,ラタトース発酵性をこの菌株に付与する必要がある.そこで,Lactobacillus casei subsp. caseiのラクトース非発酵性(Lac-株である.34143S(ストレプトマイシン耐性,Strr)および34143P(ペニシリン耐性,Penr)株を分離し,それらを受容菌として液体培地中や寒天培地上での接合法によって,Lac+交配菌の作出を検討した.その結果,受容菌と供与菌Lactobacillus delbrueckii subsp. bulgaricus7235との交配で得られたLac+StrrやLac+Penrの交配菌,Lactobacillus rhamnosus IFO3245とのLac+StrrやLac+Penr株およびStreptococcus salivarius subsp. Thermophilus 18235とのLac+Penr株を3回の繰り返し試験で再現性高く得ることができた.それらの接合頻度は,供与菌当たり,1.1×10-5から1.6×10-2の範囲であり,比較的高い頻度でLac+交配菌の得られる組合せもあった. 得られた交配菌はほとんどが脱脂乳を凝固し,ラクトース発酵性は安定であった.また交配菌の糖類発酵性やその他の性状試験から,受容菌と供与菌にない性質を発現した交配菌や受容菌のもつ性質の一部を欠落した交配菌もあった.しかし形態はいずれも受容菌と同一であった.これらのラクトース発酵性交配菌の出現は,自然突然変異,形質導入および形質転換によるものではなく,受容菌と供与菌の細胞接合によりラクトース発酵性が発現したものと考えられた.またこのラクトース発酵性の発現は,プラスミドの伝達によるものではないと思われた.しかし詳細については今後さらに検討する必要がある

Evidence of mature adipocyte proliferation regulated by proliferin

Despite much research, whether mature adipocytes proliferate remains controversial. Here, we examined 5-bromo-2′-deoxyuridine (BrdU)-labelling of mature adipocytes. Although BrdU incorporation into subcutaneous adipocytes was less than that in visceral adipocytes, pioglitazone (Pio) treatment increased BrdU incorporation in subcutaneous, but not visceral, adipocytes in rats. Fully differentiated 3T3-L1 adipocytes exhibited an increase in cell number and BrdU incorporation with time, with this increase enhanced by Pio treatment. We therefore screened for genes that encode growth factors regulated by Pio, and selected proliferin (PLF). Both gene silencing of PLF by small interfering RNA and treatment with anti-PLF antibody suppressed proliferation in 3T3-L1 adipocytes. In adipocytes isolated from Pio-treated rats, the tissue-specific pattern of PLF expression was similar to that of BrdU incorporation. Administration of an anti-PLF antibody to mice reduced BrdU incorporation into adipocytes. Mature adipocytes thus have the ability to replicate, and this proliferation is positively regulated by PLF

Separation of Lanthanoids by SiO 2 -P Adsorbent Impregnated with Extractants -13103

ABSTRACT The adsorption and separation properties of lanthanoids (Ln) were investigated for the mutual separation of trivalent minor actinoids (MA) by using different adsorbents of hydrophobic extractant/SiO 2 -P in solutions of hydrophilic extractant/HNO 3 . The synergistic effect by use of the hydrophobic and hydrophilic extractants was evaluated by batch and column experiments. The results of batch expariments showed the synergistic effect which lowered the K d values of Ln. In column experiments, effective mutual separation between Nd and Sm was demonstrated. These results suggest that the mutual separation between Am and Cm is possible because the K d values of Am and Cm are probably similar to those of Nd and Sm

Novel COL11A1 mutation in familial Stickler syndrome

Stickler syndrome (STL) is an autosomal, dominantly inherited, clinically variable and genetically heterogeneous connective tissue disorder characterized by ocular, auditory, orofacial and skeletal abnormalities. We conducted targeted resequencing using a next-generation sequencer for molecular diagnosis of a 2-year-old girl who was clinically suspected of having STL with Pierre Robin sequence. We detected a novel heterozygous missense mutation, NM_001854.3:n.4838G>A [NM_001854.3 (COL11A1_v001):c.4520G>A], in COL11A1, resulting in a Gly to Asp substitution at position 1507 [NM_001854.3(COL11A1_i001)] within one of the collagen-like domains of the triple helical region. The same mutation was detected in her 4-year-old brother with cleft palate and high-frequency sensorineural hearing loss

Genetic Alterations in Gorlin Syndrome

Gorlin syndrome (GS) is an autosomal dominant disorder that predisposes affected individuals to developmental defects and tumorigenesis, and caused mainly by heterozygous germline PTCH1 mutations. Despite exhaustive analysis, PTCH1 mutations are often unidentifiable in some patients; the failure to detect mutations is presumably because of mutations occurred in other causative genes or outside of analyzed regions of PTCH1, or copy number alterations (CNAs). In this study, we subjected a cohort of GS-affected individuals from six unrelated families to next-generation sequencing (NGS) analysis for the combined screening of causative alterations in Hedgehog signaling pathway-related genes. Specific single nucleotide variations (SNVs) of PTCH1 causing inferred amino acid changes were identified in four families (seven affected individuals), whereas CNAs within or around PTCH1 were found in two families in whom possible causative SNVs were not detected. Through a targeted resequencing of all coding exons, as well as simultaneous evaluation of copy number status using the alignment map files obtained via NGS, we found that GS phenotypes could be explained by PTCH1 mutations or deletions in all affected patients. Because it is advisable to evaluate CNAs of candidate causative genes in point mutation-negative cases, NGS methodology appears to be useful for improving molecular diagnosis through the simultaneous detection of both SNVs and CNAs in the targeted genes/regions

Anti-tachycardia pacing degenerated fast ventricular tachycardia into undetectable life-threatening tachyarrhythmia in a patient with non-ischemic dilated cardiomyopathy

SummaryA 45-year-old man with dilated cardiomyopathy was admitted to our hospital due to congestive heart failure (CHF). Despite the optimal medical treatment, his condition had not improved because of severe left ventricular dysfunction. Because he experienced non-sustained ventricular tachycardia (VT), a biventricular implantable cardioverter-defibrillator (Bi-V ICD) was implanted for reduction of dyssynchrony and primary prevention of lethal tachyarrhythmia. After discharge, he developed CHF and was transported to our hospital by ambulance. In the ambulance, monomorphic sustained VT with 200bpm suddenly occurred. The ICD detected it as fast VT and anti-tachycardia pacing (ATP) was delivered. After the ATP therapy, RR intervals of VT became irregular and prolonged. Ventricular fibrillation-like electrical activity was recorded by a far-field electrogram from the defibrillator, but the tachycardia cycle length exceeded 400ms which is under the tachycardia detection rate. The device failed to deliver a shock and the patient had to be rescued with an external shock. This is a rare case of fast VT that degenerated into undetectable life-threatening tachyarrhythmia by ATP

Association between shelter crowding and incidence of sleep disturbance among disaster evacuees: a retrospective medical chart review study

Objectives: We determined whether crowding at emergency shelters is associated with a higher incidence of sleep disturbance among disaster evacuees and identified the minimum required personal space at shelters. Design: Retrospective review of medical charts. Setting: 30 shelter-based medical clinics in Ishinomaki, Japan, during the 46 days following the Great Eastern Japan Earthquake and Tsunami in 2011. Participants: Shelter residents who visited eligible clinics. Outcome measures Based on the result of a locally weighted scatter-plot smoothing technique assessing the relationship between the mean space per evacuee and cumulative incidence of sleep disturbance at the shelter, eligible shelters were classified into crowded and non-crowded shelters. The cumulative incidence per 1000 evacuees was compared between groups, using a Mann-Whitney U test. To assess the association between shelter crowding and the daily incidence of sleep disturbance per 1000 evacuees, quasi–least squares method adjusting for potential confounders was used. Results: The 30 shelters were categorised as crowded (mean space per evacuee <5.0 m2, 9 shelters) or non-crowded (≥5.0 m2, 21 shelters). The study included 9031 patients. Among the eligible patients, 1079 patients (11.9%) were diagnosed with sleep disturbance. Mean space per evacuee during the study period was 3.3 m2 (SD, 0.8 m2) at crowded shelters and 8.6 m2 (SD, 4.3 m2) at non-crowded shelters. The median cumulative incidence of sleep disturbance did not differ between the crowded shelters (2.3/1000 person-days (IQR, 1.6–5.4)) and non-crowded shelters (1.9/1000 person-days (IQR, 1.0–2.8); p=0.20). In contrast, after adjusting for potential confounders, crowded shelters had an increased daily incidence of sleep disturbance (2.6 per 1000 person-days; 95% CI 0.2 to 5.0/1000 person-days, p=0.03) compared to that at non-crowded shelters. Conclusions: Crowding at shelters may exacerbate sleep disruptions in disaster evacuees; therefore, appropriate evacuation space requirements should be considered