Fighting the Learning Crisis in Developing Countries: A Randomized Experiment of Self-Learning at the Right Level

This study investigates the effectiveness of a globally popular method of self-learning at the right level in improving learning outcomes—the cognitive and noncognitive abilities of disadvantaged students—in a developing country, Bangladesh. Using a randomized controlled trial design, we find substantial improvements in cognitive abilities measured by math test scores and catch-up effects in terms of noncognitive abilities or personality traits measured through a self-esteem scale. Moreover, our study is the first to use alternative cognitive ability measures, that is, time reduction as well as time-adjusted test score, which are critical dimensions of cognitive development. Subsequently, we investigate the long-term effects using students’ math results of the national-level exam. We find a reasonable longer-term impact on cognitive abilities 20 months after the intervention for younger students. Our estimates indicate that the program’s benefits exceed its costs

Haste Makes No Waste: Positive Peer Effects of Classroom Speed Competition on Learning

This study investigates the effects of speed competition in classrooms on young pupils' learning outcomes. To examine how faster peers' speed affects slower pupils' speed and learning, we employ students' daily progress data in a self-learning programme at BRAC primary schools in Bangladesh. The programme's unique setting allows us to address the reflection problem reasonably well. While speed competition could generate negative consequences, our results show overall positive peer effects on problem-solving time and scores. The effects are stronger among peers with similar abilities, without negatively affecting others. Our results show efficiency gains from non-market competition in education and learning

Leukemia autopsies in Japan

For the purpose to know whether the annual increase of leukemia incidence in Japan is due to some leukemogenic factors or due to the increased detection rate, the authors made some statistical survey of autopsy cases in which the diagnosis is reliable and not any type of leukemias escape the detection. The results showed that acute leukemias, which are found mostly in younger age, is actually increasing. In addition, it has been deduced that among the suspected factors the increase in ionizing radiation will be one of the most probable factors for the increase in leukemia incidence</p

Class I and II NADPH-cytochrome P450 reductases exhibit different roles in triterpenoid biosynthesis in Lotus japonicus

Istiandari P., Yasumoto S., Seki H., et al. Class I and II NADPH-cytochrome P450 reductases exhibit different roles in triterpenoid biosynthesis in Lotus japonicus. Frontiers in Plant Science 14, 1214602 (2023); https://doi.org/10.3389/fpls.2023.1214602.Cytochrome P450 monooxygenases (CYPs) are enzymes that play critical roles in the structural diversification of triterpenoids. To perform site-specific oxidations of the triterpene scaffold, CYPs require electrons transferred by NADPH-cytochrome P450 reductase (CPR), which is classified into two main classes, class I and class II, based on their structural difference. Lotus japonicus is a triterpenoids-producing model legume with one CPR class I gene (LjCPR1) and a minimum of two CPR class II genes (LjCPR2-1 and LjCPR2-2). CPR classes I and II from different plants have been reported to be involved in different metabolic pathways. By performing gene expression analyses of L. japonicus hairy root culture treated with methyl jasmonate (MeJA), this study revealed that LjCPR1, CYP716A51, and LUS were down-regulated which resulted in no change in betulinic acid and lupeol content. In contrast, LjCPR2s, bAS, CYP93E1, and CYP72A61 were significantly upregulated by MeJA treatment, followed by a significant increase of the precursors for soyasaponins, i.e. β-amyrin, 24-OH β-amyrin, and sophoradiol content. Triterpenoids profile analysis of LORE1 insertion and hairy root mutants showed that the loss of the Ljcpr2-1 gene significantly reduced soyasaponins precursors but not in Ljcpr1 mutants. However, Ljcpr1 and Ljcpr2-1 mutants showed a significant reduction in lupeol and oleanolic, ursolic, and betulinic acid contents. Furthermore, LjCPR1, but not LjCPR2, was crucial for seed development, supporting the previous notion that CPR class I might support plant basal metabolism. This study suggests that CPR classes I and II play different roles in L. japonicus triterpenoid biosynthesis

Glycyrrhizin Production in Licorice Hairy Roots Based on Metabolic Redirection of Triterpenoid Biosynthetic Pathway by Genome Editing

Chiyo Naoki, Seki Hikaru, Kanamoto Takuya, et al. Glycyrrhizin Production in Licorice Hairy Roots Based on Metabolic Redirection of Triterpenoid Biosynthetic Pathway by Genome Editing. Plant And Cell Physiology 9, 505 (2023); https://doi.org/10.1093/pcp/pcad161.Glycyrrhizin, a type of the triterpenoid saponin, is a major active ingredient contained in the roots of the medicinal plant licorice (Glycyrrhiza uralensis, G. glabra and G. inflata), and is used worldwide in diverse applications, such as herbal medicines and sweeteners. The growing demand for licorice threatens wild resources and therefore a sustainable method of supplying glycyrrhizin is required. With the goal of establishing an alternative glycyrrhizin supply method not dependent on wild plants, we attempted to produce glycyrrhizin using hairy root culture. We tried to promote glycyrrhizin production by blocking competing pathways using CRISPR/Cas9-based gene editing. CYP93E3 CYP72A566 double-knockout (KO) and CYP93E3 CYP72A566 CYP716A179 LUS1 quadruple-KO variants were generated, and a substantial amount of glycyrrhizin accumulation was confirmed in both types of hairy root. Furthermore, we evaluated the potential for promoting further glycyrrhizin production by simultaneous CYP93E3 CYP72A566 double-KO and CYP88D6-overexpression. This strategy resulted in a 3-fold increase (∼1.4 mg/g) in glycyrrhizin accumulation in double-KO/CYP88D6-overexpression hairy roots, on average, compared with that of double-KO hairy roots. These findings demonstrate that the combination of blocking competing pathways and overexpression of the biosynthetic gene is important for enhancing glycyrrhizin production in G. uralensis hairy roots. Our findings provide the foundation for sustainable glycyrrhizin production using hairy root culture. Given the widespread use of genome editing technology in hairy roots, this combined with gene knockout and overexpression could be widely applied to the production of valuable substances contained in various plant roots

Disruption of a licorice cellulose synthase-derived glycosyltransferase gene demonstrates its in planta role in soyasaponin biosynthesis

The version of record of this article, first published in Plant Cell Reports, is available online at Publisher’s website: https://doi.org/10.1007/s00299-023-03095-6Key message: CRISPR–Cas9-mediated disruption of a licorice cellulose synthase-derived glycosyltransferase gene, GuCSyGT, demonstrated the in planta role of GuCSyGT as the enzyme catalyzing 3-O-glucuronosylation of triterpenoid aglycones in soyasaponin biosynthesis. Abstract: Triterpenoid glycosides (saponins) are a large, structurally diverse group of specialized metabolites in plants, including the sweet saponin glycyrrhizin produced by licorice (Glycyrrhiza uralensis) and soyasaponins that occur widely in legumes, with various bioactivities. The triterpenoid saponin biosynthetic pathway involves the glycosylation of triterpenoid sapogenins (the non-sugar part of triterpenoid saponins) by glycosyltransferases (GTs), leading to diverse saponin structures. Previously, we identified a cellulose synthase-derived GT (CSyGT), as a newly discovered class of triterpenoid GT from G. uralensis. GuCSyGT expressed in yeast, which could transfer the sugar glucuronic acid to the C3 position of glycyrrhetinic acid and soyasapogenol B, which are the sapogenins of glycyrrhizin and soyasaponin I, respectively. This suggested that GuCSyGT is involved in the biosynthesis of glycyrrhizin and soyasaponin I. However, the in planta role of GuCSyGT in saponin biosynthesis remains unclear. In this study, we generated GuCSyGT-disrupted licorice hairy roots using CRISPR–Cas9-mediated genome editing and analyzed the saponin content. This revealed that soyasaponin I was completely absent in GuCSyGT-disrupted lines, demonstrating the in planta role of GuCSyGT in saponin biosynthesis

エンドウのエリシター誘導性遺伝子発現におけるAAAGモチーフとPsDof1タンパク質の関与

Recently, we, isolated cDNA clone, PsDof1, from clicitor-treated pea cDNA library. The putative gene product, a PsDof1, encodes DNA binding protein that specifically binds the DNA fragment containing AAAG core sequence. In this paper we report that GST-PsDof1 fusion protein specifically binds to the promoter region containing AAAG core sequence(s) of PsCHS1, one of the elicitor-inducible genes encoding chalcone synthase (CHS). Furthermore the addition of DNA fragment containing AAAG motif to the 35S minimal promoter provided the elicitor-responsibility in transient transfection assay using pea protoplasts. These results suggest that PsDof1 might be involved in defense responses by acitivating the transcription by a binding to AAAG core sequence in the promoter of the defense-related genes in pea.エリシターを処理したエンドウ上胚軸由来のRNAから作成されたcDNAライブラリーからエリシター処理により発現が増高する遺伝子候補のcDNAとしてPsDof1が単離された．大腸菌で生産されたGST-PsDof１融合タンパク質はAAAG配列をコアとするDNAに結合することが明らかにされている．本論文ではGST-PsDof１がエリシター応答性遺伝子の一つ，PsCHS1のプロモーター上のAAAGまたはCTTT配列を有する断片に特異的に結合することを明らかにした．更にAAAG配列のエリシター応答性シスエレメントとしての機能を解析するため，AAAG配列を４回繰り返したユニットをCaMV35Ｓの最小プロモーターとCATレポーター遺伝子に連結したキメラ遺伝子を構築し，エンドウプロトプラストにエレクトロポレーション法により導入した．CAT活性を指にプロモーター活性を調べたところ，AAAG配列を有するプロモーターは，エリシター処理により活性化されることが明らかとなった．これらの結果はPsDof１がエリシター応答性防御遺伝子のプロモーター上のAAAG配列に結合し，転写を活性化させる可能性を示唆している

Comparative functional analysis of CYP71AV1 natural variants reveals an important residue for the successive oxidation of amorpha-4,11-diene

AbstractArtemisinin is an antimalarial sesquiterpenoid isolated from the aerial parts of the plant Artemisia annua. CYP71AV1, a cytochrome P450 monooxygenase was identified in the artemisinin biosynthetic pathway. CYP71AV1 catalyzes three successive oxidation steps at the C12 position of amorpha-4,11-diene to produce artemisinic acid. In this study, we isolated putative CYP71AV1 orthologs in different species of Artemisia. Comparative functional analysis of CYP71AV1 and its putative orthologs, together with homology modeling, enabled us to identify an amino acid residue (Ser479) critical for the second oxidation reaction catalyzed by CYP71AV1. Our results clearly show that a comparative study of natural variants is useful to investigate the structure–function relationships of CYP71AV1

Supersymmetric large-N reduced model with multiple matter

We showed in hep-th/0303210 that the Dijkgraaf-Vafa theory can be regarded as large-N reduction in the case of $\mathcal{N}=1$ supersymmetric U(N) gauge theories, with single adjoint matter. We generalize this to gauge theories with gauge groups being the products of some unitary groups coupled to bifundamental or fundamental matter. We show that some large-N reduced models of these theories are supermatrix models, whose free energy is equivalent to the prepotentials of the original gauge theories. The supermatrix model in our approach should be taken in the Veneziano limit $N_c,N_f \to \infty$ with $N_f/N_c$ fixed.Comment: 24 pages, LaTeX. to appear in Nucl. Phys.

Transgenic Monkey Model of the Polyglutamine Diseases Recapitulating Progressive Neurological Symptoms

Age-associated neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and the polyglutamine (polyQ) diseases, are becoming prevalent as a consequence of elongation of the human lifespan. Although various rodent models have been developed to study and overcome these diseases, they have limitations in their translational research utility owing to differences from humans in brain structure and function and in drug metabolism. Here, we generated a transgenic marmoset model of the polyQ diseases, showing progressive neurological symptoms including motor impairment. Seven transgenic marmosets were produced by lentiviral introduction of the human ataxin 3 gene with 120 CAG repeats encoding an expanded polyQ stretch. Although all offspring showed no neurological symptoms at birth, three marmosets with higher transgene expression developed neurological symptoms of varying degrees at 3–4 months after birth, followed by gradual decreases in body weight gain, spontaneous activity, and grip strength, indicating time-dependent disease progression. Pathological examinations revealed neurodegeneration and intranuclear polyQ protein inclusions accompanied by gliosis, which recapitulate the neuropathological features of polyQ disease patients. Consistent with neuronal loss in the cerebellum, brain MRI analyses in one living symptomatic marmoset detected enlargement of the fourth ventricle, which suggests cerebellar atrophy. Notably, successful germline transgene transmission was confirmed in the second-generation offspring derived from the symptomatic transgenic marmoset gamete. Because the accumulation of abnormal proteins is a shared pathomechanism among various neurodegenerative diseases, we suggest that this new marmoset model will contribute toward elucidating the pathomechanisms of and developing clinically applicable therapies for neurodegenerative diseases.ArticleeNeuro.4(2):e0250(2017)journal articl