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101.

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated endonuclease 9 (Cas9) system is being rapidly developed for mutagenesis in higher plants. Ideally, foreign DNA introduced by this system is removed in the breeding of edible crops and vegetables. Here, we report an efficient generation of Cas9-free mutants lacking an allergenic gene, Gly m Bd 30K, using biolistic transformation and the CRISPR/Cas9 system. Five transgenic embryo lines were selected on the basis of hygromycin resistance. Cleaved amplified polymorphic sequence analysis detected only two different mutations in e all of the lines. These results indicate that mutations were induced in the target gene immediately after the delivery of the exogenous gene into the embryo cells. Soybean plantlets (T0 plants) were regenerated from two of the transgenic embryo lines. The segregation pattern of the Cas9 gene in the T1 generation, which included Cas9-free plants, revealed that a single copy number of transgene was integrated in both lines. Immunoblot analysis demonstrated that no Gly m Bd 30K protein accumulated in the Cas9-free plants. Gene expression analysis indicated that nonsense mRNA decay might have occurred in mature mutant seeds. Due to the efficient induction of inheritable mutations and the low integrated transgene copy number in the T0 plants, we could remove foreign DNA easily by genetic segregation in the T1 generation. Our results demonstrate that biolistic transformation of soybean embryos is useful for CRISPR/Cas9-mediated site-directed mutagenesis of soybean for human consumption.

  相似文献   
102.
Miliin is a serine protease purified from the latex of Euphorbia milii. This work reports the effect of pH and temperature on the catalytic activity of miliin, using fluorescence resonance energy transfer (FRET) substrates. Miliin displayed the highest activity at pH 9 and 35 °C. Subsite mapping shows that subsites S2 to S2′ prefer uncharged residues. The S2 subsite prefers hydrophobic aliphatic amino acids (Val, Pro and Ile) and defines the cleavage site. This work is the first one that reports subsite mapping of Euphorbiacea proteases. The N-terminal sequence showed higher similarity (40%) with the serine protease LIM9 isolated from Lilium. The presence of Tyr, Pro and Lys at positions 2, 5 and 10 respectively, were observed for most of the serine proteases used for comparison. The N-terminal sequence has striking differences with those reported previously for milin and eumiliin, other serine proteases isolated from the latex of E. milii.  相似文献   
103.
Behavioural lateralisation is an effective way for animals to manage daily tasks by specialising behaviour to either side of the body. Many types of lateralisation are linked to the function of each brain hemisphere. Lateralisation of monitoring behaviour in mother–infant relationships occurs in a wide range of mammals, where infants frequently use their left eye to monitor their mother. However, few studies have focused on this type of spatial relationships among adults in daily life, such as during foraging. The present study focused on monitoring adult feral horse behaviour using quantitative analysis of spatial relationships, using drone technology. We found that horses form a localised spatial relationship with their nearest neighbour. Specifically, the nearest neighbour was located to the left rear of a target individual significantly more frequently than to the right rear. Furthermore, the nearest neighbour was less frequently located behind a target individual. We propose that this relationship is caused by a left-eye preference, because information via the left eye predominantly proceeds to the right hemisphere, which is dominant for social processing.  相似文献   
104.
The binary structure II hydrogen–tetrahydrofuran (THF) hydrate was studied with molecular dynamics simulation. The simulations were carried out at 300, 310 K and 10.1 MPa, and with various contents of hydrogen and THF. The migrations of hydrogen molecules from cage to cage were observed. The migration process of hydrogen was also analysed, and the diffusion coefficients of hydrogen in the hydrate were calculated. The calculated diffusion coefficients qualitatively agreed with the experimental data. Double and quintet occupancies of hydrogen molecules were observed in the small and large cages, respectively, without changing the hydrate structure.  相似文献   
105.
Medical students are at higher risk for depression, affecting not only their lives but also patient care. This article studied a population of medical students engaged in lecture‐based learning regarding the presence of depressive symptoms and its relation to morningness‐eveningness. Depressive symptoms were assessed by the Beck Depressive Inventory scale (BDI>10), and diurnal preference was assessed by the Horne & Östberg Morningness/Eveningness Questionnaire (MEQ). Family history of depression and involvement in regular physical activity were also investigated. A total of 161 students, 77 (47.8%) males, aged 19 to 30 yrs (22.1±2.1) living in a city close to the equator were evaluated. Fifty‐three individuals (32.9%) had depressive symptoms. Depressive individuals showed a trend to be female (p=0.07). Also, female gender showed a non‐significant shift toward morningness. Fifty‐eight (36.0%) subjects participated in regular physical activity. In 57 cases (35.4%), there was a history of depression in the family. Fifteen individuals (9.3%) were definitely evening type, 42 (26.1%) were moderately evening type, 44 (27.3%) were indifferent, 42 (26.1%) were moderately morning type, and 18 (11.2%) were definitely morning type. Family history of depression (OR=0.29, 95% CI=1.37–6.12) and sedentary life (OR=0.28, 95% CI=0.12–0.65) were associated with depressive symptoms. Eveningness was associated with depressive symptoms (OR=0.66, 95% CI=0.50–0.88), and this association remained significant after adjusting for the presence of familial depression and physical activity (OR=0.71, 95% CI=0.52–0.95). In conclusion, depressive symptoms are independently associated with “eveningness” in medical students. These results should be confirmed by future studies involving a larger number of subjects.  相似文献   
106.
p24 family proteins are evolutionarily conserved transmembrane proteins involved in the early secretory pathway. Saccharomyces cerevisiae has 8 known p24 proteins that are classified into four subfamilies (p24α, -β, -γ, and -δ). Emp24 and Erv25 are the sole members of p24β and -δ, respectively, and deletion of either destabilizes the remaining p24 proteins, resulting in p24 null phenotype (p24Δ). We studied genetic and physical interactions of p24α (Erp1, -5, and -6) and γ (Erp2, -3, and -4). Deletion of the major p24α (Erp1) partially inhibited p24 activity as reported previously. A second mutation in either Erp5 or Erp6 aggravated the erp1Δ phenotype, and the triple mutation gave a full p24Δ phenotype. Similar genetic interactions were observed among the major p24γ (Erp2) and the other two γ members. All the p24α/γ isoforms interacted with both p24β and -δ. Interaction between p24β and -δ was isoform-selective, and five major α/γ pairs were detected. These results suggest that the yeast p24 proteins form functionally redundant αβγδ complexes. We also identified Rrt6 as a novel p24δ isoform. Rrt6 shows only limited sequence identity (∼15%) to known p24 proteins but was found to have structural properties characteristic of p24. Rrt6 was induced when cells were grown on glycerol and form an additional αβγδ complex with Erp3, Erp5, and Emp24. This complex was mainly localized to the Golgi, whereas the p24 complex containing Erv25, instead of Rrt6 but otherwise with the same isoform composition, was found mostly in the ER.  相似文献   
107.
A thermotolerant fungus identified as Aspergillus niveus was isolated from decomposing materials and it has produced excellent levels of hydrolytic enzymes that degrade plant cell walls. A. niveus germinated faster at 40 °C, presenting protein levels almost twofold higher than at 25 °C. The crude extract of the A. niveus culture was purified by diethylaminoethyl (DEAE)-cellulose, followed by Biogel P-100 column. Polygalacturonase (PG) is a glycoprotein with 37.7 % carbohydrate, molecular mass of 102.6 kDa, and isoelectric point of 5.4. The optimum temperature and pH were 50 °C and 4.0–6.5, respectively. The enzyme was stable at pH 3.0 to 9.0 for 24 h. The DEAE-cellulose derivative was about sixfold more stable at 60 °C than the free enzyme. Moreover, the monoaminoethyl-N-aminoethyl-agarose derivative was tenfold more stable than the free enzyme. PG was 232 % activated by Mn2+. The hydrolysis product of sodium polypectate corresponded at monogalacturonic acid, which classifies the enzyme as an exo-PG. The K m, V max, K cat, and K cat/K m values were 6.7 mg/ml, 230 U/mg, 393.3/s, and 58.7 mg/ml/s, respectively. The N-terminal amino acid sequence presented 80 % identity with PglB1, PglA2, and PglA3 putative exo-PG of Aspergillus fumigatus and an exo-PG Neosartorya fischeri.  相似文献   
108.

Objective

The objective was to investigate how postural control in knee osteoarthritis (KOA) patients, with different structural severities and pain levels, is reorganized under different sensory conditions.

Methods

Forty-two obese patients (BMI range from 30.1 to 48.7 kg*m−2, age range from 50 to 74 years) with KOA were evaluated. One minute of quiet standing was assessed on a force platform during 4 different sensory conditions, applied 3 times at random: Eyes open (EO) and eyes closed (EC) standing on firm and soft (foam) surfaces (EO-soft and EC-soft). Centre of pressure (Cop) standard deviation, speed, range and Cop mean position in both directions (anterior-posterior and medial-lateral) were extracted from the force platform data. Structural disease severity was assessed from semiflexed standing radiographs and graded by the Kellgren and Lawrence (KL) score. Pain intensity immediately before the measurements was assessed by numeric rating scale (range: 0–10).

Results

The patients were divided into “less severe” (KL 1 and 2, n = 24) and “severe” (KL>2, n = 18) group. The CoP range in the medial-lateral direction was larger in the severe group when compared with the less severe group during EC-soft condition (P<0.01). Positive correlation between pain intensity and postural sway (range in medial-lateral direction) was found during EC condition, indicating that the higher the pain intensity, the less effective is the postural control applied to restore an equilibrium position while standing without visual information.

Conclusion

The results support that: (i) the postural reorganization under manipulation of the different sensory information is worse in obese KOA patients with severe degeneration and/or high pain intensity when compared with less impaired patients, and (ii) higher pain intensity is related to worse body balance in obese KOA patients.  相似文献   
109.
110.
miR-146a plays important roles in cancer as it directly targets NUMB, an inhibitor of Notch signaling. miR-146a is reportedly regulated by a G>C polymorphism (SNP; rs2910164). This polymorphism affects various cancers, including colorectal cancer (CRC). However, the clinical significance of miR-146a polymorphism in CRC remains unclear. A total of 59 patients with CRC were divided into 2 groups: a CC/CG genotype (n = 32) and a GG genotype (n = 27), based on the miR-146a polymorphism. cDNA microarray analysis was performed using 59 clinical samples. Significantly enriched gene sets in each genotype were extracted using GSEA. We also investigated the association between miR-146a polymorphism and miR-146a, NUMB expression or migratory response in CRC cell lines. The CC/CG genotype was associated with significantly more synchronous liver metastasis (p = 0.007). A heat map of the two genotypes showed that the expression profiles were clearly stratified. GSEA indicated that Notch signaling and JAK/STAT3 signaling were significantly associated with the CC/CG genotype (p = 0.004 and p = 0.023, respectively). CRC cell lines with the pre-miR-146a/C revealed significantly higher miR-146a expression (p = 0.034) and higher NUMB expression and chemotactic activity. In CRC, miR-146a polymorphism is involved in liver metastasis. Identification of this polymorphism could be useful to identify patients with a high risk of liver metastasis in CRC.  相似文献   
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