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1.
Rice eating and cooking quality (ECQ) is a major concern of breeders and consumers, determining market competitiveness worldwide. Rice grain protein content (GPC) is negatively related to ECQ, making it possible to improve ECQ by manipulating GPC. However, GPC is genetically complex and sensitive to environmental conditions; therefore, little progress has been made in traditional breeding for ECQ. Here, we report that CRISPR/Cas9-mediated knockout of genes encoding the grain storage protein glutelin rapidly produced lines with downregulated GPC and improved ECQ. Our finding provides a new strategy for improving rice ECQ.  相似文献   
2.
改进了一种分析磷酸酶活性的终止酶反应方法.该方法通过在酶反应进行到一定程度时,在反应混合物中加入酶反应终止液(1mol/L NaOH-0.2mol/L EDTA),从而使测定更简捷、精确.  相似文献   
3.
刘志荣  覃营  刘晟源  刘演 《西北植物学报》2021,41(11):1971-1974
报道了中国兰科(Orchidaceae)鹿角兰属(Pomatocalpa)一新记录种——纹瓣鹿角兰[P. tonkinense (Gagnep.) Seidenf.],凭证标本保存于广西植物研究所标本馆(IBK)。纹瓣鹿角兰的花序疏生多数花,萼片、花瓣均具2条紫色条纹,中萼片及花瓣远长于侧萼片,与中国原记录的2种鹿角属植物容易区分。该研究提供了新记录种的形态描述、中国鹿角兰属植物图版及分种检索表。  相似文献   
4.
Muskmelon (Cucumis melo L.) wilt caused by Fusarium oxysporum f. sp. melonis leads to severe economic losses. A bio-organic fertilizer (BIO) fortified with an antagonistic strain of Bacillus subtilis Y-IVI was used to control this disease. Pot experiments were carried out to investigate the efficacy and to elucidate biocontrol mechanisms for the disease. BIO significantly reduced the disease incidence. Population of F. oxysporum in plant shoots of the BIO treatment were about 1000-fold lower than the control. Population of Y-IVI remained high in muskmelon rhizosphere of the BIO treatment during the experiment. Concentration of antifungal lipopeptides, iturin A, in the BIO treatment was significantly higher than other treatments. Ten days after transplantation, the salicylic acid content in BIO-treated plant leaves was significantly higher than control. In conclusion, BIO effectively controlled muskmelon wilt, possibly because the antagonistic microbes effectively colonize the plant rhizosphere and shoots to preclude pathogen invasion. Furthermore, Y-IVI produces antifungal lipopeptides in the rhizosphere.  相似文献   
5.
CRISPR/Cas技术在抗除草剂作物育种中的研究与应用进展   总被引:1,自引:0,他引:1  
CRISPR/Cas系统是一种简单、低成本、高效、精准的基因编辑技术,该技术能够进行基因的定向改造,加速新品种培育进程,在种质资源创制中的应用潜力较高。概述了CRISPR/Cas系统的技术原理及其在作物抗除草剂育种中的应用,简要指出了目前CRISPR/Cas技术在抗除草剂种质创制及应用过程中存在的问题及发展方向,以期为今后利用CRISPR/Cas技术创制抗除草剂新种质提供理论依据。  相似文献   
6.
从12株细菌菌株中筛选到一株产3-脱氧葡糖松还原酶的高产菌Bacillussp.2,并研究了该菌株的产酶条件。在所试验的细菌中,3-脱氧葡糖松氧化酶活性较低甚至检测不出,而还原酶活性普遍较高。该菌株最佳产酶条件为:培养基组成(%):牛肉膏0.3,牛肉蛋白陈1.0,氯化钠0.5,0.5mmol/L3-脱氧葡糖松。培养基起始pH6.6,30℃振荡培养48h,产酶量最高,酶活力可达36.4u/g。3-脱氧葡糖松对产酶有诱导作用,而甲基乙二醛对产酶有抑制作用。  相似文献   
7.

Background and Objective

Conflicting data have been reported on the association between tumor necrosis factor (TNF) –308G>A and nitric oxide synthase 3 (NOS3) +894G>T polymorphisms and migraine. We performed a meta-analysis of case-control studies to evaluate whether the TNF –308G>A and NOS3 +894G>T polymorphisms confer genetic susceptibility to migraine.

Method

We performed an updated meta-analysis for TNF –308G>A and a meta-analysis for NOS3 +894G>T based on studies published up to July 2014. We calculated study specific odds ratios (OR) and 95% confidence intervals (95% CI) assuming allele contrast, dominant model, recessive model, and co-dominant model as pooled effect estimates.

Results

Eleven studies in 6682 migraineurs and 22591 controls for TNF –308G>A and six studies in 1055 migraineurs and 877 controls for NOS3 +894G>T were included in the analysis. Neither indicated overall associations between gene polymorphisms and migraine risk. Subgroup analyses suggested that the “A” allele of the TNF –308G>A variant increases the risk of migraine among non-Caucasians (dominant model: pooled OR = 1.82; 95% CI 1.15 – 2.87). The risk of migraine with aura (MA) was increased among both Caucasians and non-Caucasians. Subgroup analyses suggested that the “T” allele of the NOS3 +894G>T variant increases the risk of migraine among non-Caucasians (co-dominant model: pooled OR = 2.10; 95% CI 1.14 – 3.88).

Conclusions

Our findings appear to support the hypothesis that the TNF –308G>A polymorphism may act as a genetic susceptibility factor for migraine among non-Caucasians and that the NOS3 +894G>T polymorphism may modulate the risk of migraine among non-Caucasians.  相似文献   
8.
Xu  Zhenzhen  Jiang  Jianxiang  Xu  Shengyuan  Xie  Zunchun  He  Pei  Jiang  Shishi  Xu  Renshi 《Cellular and molecular neurobiology》2022,42(4):1035-1046

Nerve growth factor (NGF) is a protective factor of neural cells; the possible relationship between the NGF and the pathogenesis of amyotrophic lateral sclerosis (ALS) hasn’t been completely known. In this study, we observed and analyzed the expression and distribution of NGF, as well as the possible relationship between the NGF expression and distribution and the neural cell death in both SOD1 wild-type (WT) and Tg(SOD1*G93A)1Gur (TG) mice applying the fluorescence immunohistochemistry method. The results showed that the expression and distribution of NGF in the anterior horn (AH), the lateral horn (LH), and the surrounding central canal (CC) significantly increased at the supper early stage of ALS (Pre-onset stage) and the early stage (Onset stage), but the NGF expression and distribution in the AH, the LH, and the surrounding CC significantly reduced at the progression stage. The astrocyte, neuron, and oligodendrocyte produced the NGF and the neural precursor cells (NPCs) produced the NGF. The neural cell death gradually increased accompanying with the reduction of NGF expression and distribution. Our data suggested that the NGF was a protective factor of neural cells, because the neural cells in the AH, the LH, and the surrounding CC produced more NGF at the supper early and early stage of ALS; moreover, the NPCs produced the NGF. It implied that the NGF exerted the protective effect of neural cells, prevented from the neural cell death and aroused the potential of self-repair in the development of ALS.

  相似文献   
9.
A signal amplification system for electrochemiluminescence (ECL) of quantum dots (QDs) was developed by using electrochemically reduced graphene oxide (ERGO) to construct a nanobiosensing platform. Due to the structural defects of GO, the ECL emission of QDs coated on GO modified electrode was significantly quenched. After the electrochemical reduction of GO, the restoration of structural conjugation was observed with spectroscopic, morphologic and impedance techniques. Thus in the presence of dissolved O? as coreactant, the QDs/ERGO modified electrode showed ECL intensity increase by 4.2 and 178.9 times as compared with intrinsic QDs and QDs/GO modified electrodes due to the adsorption of dissolved O? on ERGO and the facilitated electron transfer. After choline oxidase (ChO) or ChO-acetylcholinesterase was further covalently cross-linked on the QDs/ERGO modified electrode, two ECL biosensors for choline and acetylcholine were fabricated, which showed the linear response ranges and detection limits of 10-210 μM and 8.8 μM for choline, and 10-250 μM and 4.7 μM for acetylcholine, respectively. This green and facile approach to prepare graphene-QDs system could be of potential applications in electronic device and bioanalysis.  相似文献   
10.
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