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61.
Fruit crops, including apple, orange, grape,banana, strawberry, watermelon, kiwifruit and tomato, not only provide essential nutrients for human life but also contribute to the major agricultural output and economic growth of many countries and regions in the world. Recent advancements in genome editing provides an unprecedented opportunity for the genetic improvement of these agronomically important fruit crops. Here, we summarize recent reports of applying CRISPR/Cas9 to fruit crops,including efforts to reduce disease susceptibility, change plant architecture or flower morphology, improve fruit quality traits, and increase fruit yield. We discuss challenges facing fruit crops as well as new improvements and platforms that could be used to facilitate genome editing in fruit crops, including d Cas9-base-editing to introduce desirable alleles and heat treatment to increase editing efficiency. In addition, we highlight what we see as potentially revolutionary development ranging from transgene-free genome editing to de novo domestication of wild relatives. Without doubt, we now see only the beginning of what will eventually be possible with the use of the CRISPR/Cas9 toolkit. Efforts to communicate with the public and an emphasis on the manipulation of consumerfriendly traits will be critical to facilitate public acceptance of genetically engineered fruits with this new technology.  相似文献   
62.
Li CY  Chu JY  Yu JK  Huang XQ  Liu XJ  Shi L  Che YC  Xie JY 《Cell research》2004,14(6):473-479
The splicing of many alternative exons in the precursor messenger RNA (pre-mRNA) is regulated by extracellular factors but the underlying molecular bases remain unclear. Here we report the differential regulation of Bcl-x pre-mRNA splicing by extracellular factors and their distinct requirements for pre-mRNA elements. In K562 leukemia cells, treatment with interleukin-6 (IL-6) or granulocyte-macrophage colony stimulating factor (GM-CSF) reduced the proportion of the Bcl-xL variant mRNA while treatment with 12-O-tetradecanoylphorbol 13-acetate (TPA) had no effect. In U251 glioma cells, however, TPA efficiently increased the Bcl-xL level. These regulations were also seen for a transfected splicing reporter mini-gene. Further analyses of deletion mutants indicate that nucleotides 1-176 of the downstream intron are required for the IL-6 effect, whereas additional nucleotides 177-284 are essential for the GM-CSF effect. As for the TPA effect, only nucleotides 1-76 are required in the downstream intron. Thus, IL-6, GM-CSF and TPA differentially regulate Bcl-x splicing and require specific intronic pre-mRNA sequences for their respective effects.  相似文献   
63.
ABSTRACT: OBJECTIVE: To study the clinico-pathological characteristics of Langerhans cell sarcoma (LCS) which involving epidermis. METHODS: A case of primary multifocal LCS was analyzed in histopathology and immunophenotype. RESULTS: A 41-year-old man with multifocal cutaneous LCS involving the inguina and waist was reported. Clinical and pathology data were available. Neoplastic cells with markedly malignant cytological features were observed. Tumor cells exhibited irregular shape with abundant and eosinophilic red staining cytoplasm; large, irregular-shaped, showing lobulated or dented nucleus and some cells with a longitudinal nuclear groove and prominent nucleoli. The tumor cells expressed CD1a, Langerin (CD207), S-100 protein, CD68 and vimentin, and did not express pan-T or B cell markers and epithelial markers. The patient died less than 1 year after diagnosis due to local recurrence and metastasis to the lung, despite the administration of local radiation and chemotherapy. CONCLUSIONS: LCS is a tumor with markedly malignant cytological features that originates from Langerhans cells. Primary multifocal neoplasms involving epidermis is even rare. Accurate diagnosis is based on the histopathological and immunohistochemical of the tumor cells.Virtual slideThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1182345104754765.  相似文献   
64.
Oridonin is a diterpenoid with anti-cancer activity that occurs in the Chinese medicinal plant Isodon rubescens and some related species. While the bioactivity of oridonin has been well studied, the extent of natural variation in the production of this compound is poorly known. This study characterizes natural variation in oridonin production in order to guide selection of populations of Isodon with highest oridonin yield. Different populations of I. rubescens and related species were collected in China, and their offspring were grown in a greenhouse. Samples were examined for oridonin content, genotyped using 11 microsatellites, and representatives were sequenced for three phylogenetic markers (ITS, rps16, trnL-trnF). Oridonin production was mapped on a molecular phylogeny of the genus Isodon using samples from each population as well as previously published Genbank sequences. Oridonin has been reported in 12 out of 74 species of Isodon examined for diterpenoids, and the phylogeny indicates that oridonin production has arisen at least three times in the genus. Oridonin production was surprisingly consistent between wild-collected parents and greenhouse-grown offspring, despite evidence of gene flow between oridonin-producing and non-producing populations of Isodon. Additionally, microsatellite genetic distance between individuals was significantly correlated with chemical distance in both parents and offspring. Neither heritability nor correlation with genetic distance were significant when the comparison was restricted to only populations of I. rubescens, but this result should be corroborated using additional samples. Based on these results, future screening of Isodon populations for oridonin yield should initially prioritize a broad survey of all species known to produce oridonin, rather than focusing on multiple populations of one species, such as I. rubescens. Of the samples examined here, I. rubescens or I. japonicus from Henan province would provide the best source of oridonin.  相似文献   
65.
王燕  李玉玲  刘燕  弓剑 《人类学学报》2017,36(3):395-404
为探讨遗传和环境因素对学龄双生子儿童身体围度及宽度等体格指标的影响,对351对6~12岁双生子儿童身高、胸围、腰围、臀围、肩宽、骨盆宽指标进行测量,计算各指标的相关指数。应用Mx软件拟合最佳结构方程模型计算各指标遗传度,分析年龄与性别的作用。结果发现,各指标拟合的最佳模型均为ACES,各测量指标的年龄方差较大(0.21~0.76),衍生指数中除腰臀比(女0.15,男0.05)外几乎均不存在年龄方差;各指标的共同环境方差变异较大(0.00~0.53);衍生指数的特殊环境因素方差(0.09~0.25)总体上高于测量指标(0.01~0.09)。校正年龄后,各指标遗传度为身高(女63%,男59%)、胸围(女84%,男88%)、身高胸围指数(女87%,男55%)、腰围(女46%,男64%)、臀围(女61%,男61%)、腰臀比(女44%,男44%)、肩宽(女78%,男78%)、骨盆宽(女62%,男62%)、身高肩宽指数(女40%,男40%)、身高骨盆宽指数(女35%,男48%)、肩宽骨盆宽指数(女24%,男24%)。结果表明学龄双生子儿童身高、胸围、身高胸围指数、臀围、肩宽、骨盆宽主要受遗传因素影响;腰臀比、身高肩宽指数、身高骨盆宽指数及肩宽骨盆宽指数受环境因素影响更大;遗传与环境因素对身高胸围指数、腰围指标的影响可能存在一定性别差异;年龄对学龄双生子儿童身体围度及宽度相关指数的影响较小。  相似文献   
66.
In this study, we aimed to study the role of growth factor receptor-bound protein 2 (Grb2) in palmitic acid-induced steatosis and other “fatty liver” symptoms in vitro. HepG2 cells, with or without stably suppressed Grb2 expression, were incubated with palmitic acid for 24 h to induce typical clinical “fatty liver” features, including steatosis, impaired glucose metabolism, oxidative stress, and apoptosis. MTT and Oil Red O assays were applied to test cell viability and fat deposition, respectively. Glucose uptake assay was used to evaluate the glucose utilization of cells. Quantitative polymerase chain reaction and Western blot were used to measure expressional changes of key markers of insulin signaling, lipid/glucose metabolism, oxidative stress, and apoptosis. After 24-h palmitic acid induction, increased fat accumulation, reduced glucose uptake, impaired insulin signaling, enhanced oxidative stress, and increased apoptosis were observed in HepG2 cells. Suppression of Grb2 in HepG2 significantly reduced fat accumulation, improved glucose metabolism, ameliorated oxidative stress, and restored the activity of insulin receptor substrate-1/Akt and MEK/ERK pathways. In addition, Grb2 deficiency attenuated hepatic apoptosis shown by reduced activation of caspase-3 and fluorescent staining. Modulation of Bcl-2 and Bak1 also contributed to reduced apoptosis. In conclusion, suppression of Grb2 expression in HepG2 cells improved hepatic steatosis, glucose metabolism, oxidative stress, and apoptosis induced by palmitic acid incubation partly though modulating the insulin signaling pathway.  相似文献   
67.
N Qin  W Ding  J Yao  K Su  L Wu  L Li 《Journal of bacteriology》2012,194(16):4469-4470
Staphylococcus capitis is a subtype of coagulase-negative staphylococci (CoNS) which could emerge as a significant pathogen causing infective endocarditis, prosthetic valve endocarditis, and late-onset sepsis. We isolated S. capitis strain QN1 from the skin swab sample of a female. Here we prepared a genome sequence for this strain consisting of 30 contigs totaling 2,430,101 bases and a GC content of 32.76%.  相似文献   
68.
入侵植物与重金属胁迫的相互作用研究进展 全球变化改变了植物群落的分布格局,包括入侵植物,而人为污染可能降低本地植物对入侵植物的抗性。因此,本文总结了近几十年本地植物、入侵植物和植物-土壤生态系统中重金属生物地球化学行为的研究,以加深我们对入侵植物与环境胁迫因子相互作用的认识。我们的研究结合已有文献报道表明:(i)入侵物种对环境胁迫的影响具有异质性, (ii)影响的大小是多变的, (iii)即使在同一影响类型内,影响类型也具有多向性。然而,入侵植物暴露在重金属环境中表现出更强的自我保护机制,对重金属的生物可利用性和毒性有正向或负向的影响。另一方面,由于入侵植物普遍具有较高的耐受性,加之本地植物暴露于有毒重金属污染时具有“逃逸行为”,重金属胁迫环境更有利于植物的成功入侵。但是,对于入侵植物的重金属等元素组成是否与污染地区的本地植物不同,目前尚无共识。因此,在全球范围内对外来入侵植物与本土植物的植物体内、凋落物和土壤污染物含量进行定量比较是今后研究的一个重要方向。  相似文献   
69.
黄土高原半干旱偏旱区草粮轮作田土壤水分恢复效应模拟   总被引:1,自引:0,他引:1  
采用实地调查和EPIC模型相结合的方法,模拟研究了黄土高原半干旱偏旱区不同草粮轮作模式的土壤水分恢复效应.结果表明:多年生苜蓿地和苜蓿翻耕后种植粮食作物农田0~10 m土层土壤湿度调查值与模拟值间的相关系数均超过0.9(P<0.01),相对均方根误差在0.05~0.16,相对误差均低于10%;模拟与实测的土壤湿度剖面分布变化趋势一致.在黄土高原半干旱偏旱区,苜蓿地深层土壤干层恢复难度较大,在种植苜蓿期间应避免8~10 m土层土壤湿度降到5.7%以下.苜蓿地适宜种植年限为4~6 a,最长不应超过8 a.苜蓿翻耕后适宜采用马铃薯→马铃薯→春小麦轮作模式进行土壤水分恢复,32~33 a后可以再次种植苜蓿.  相似文献   
70.
microRNAs (miRNAs) have been revealed to participate in the pathological process of atherosclerosis (AS). However, the exact role of miR-338-3p, a target miRNA of BMP and activin membrane-bound inhibitor (BAMBI), and its possible molecular mechanism in AS remain unidentified. In this study, we found that BAMBI was significantly decreased, whereas miR-338-3p increased in patients with AS and oxidized low-density lipoprotein (ox-LDL)-induced HUVEC cells. Furthermore, overexpression of miR-338-3p significantly decreased cell viability and elevated cell apoptosis, whereas its inhibition significantly promoted cell viability and inhibited cell apoptosis in ox-LDL-induced HUVEC cells. Moreover, miR-338-3p overexpression increased TGF-β/Smad pathway activation in ox-LDL-induced HUVEC cells. A dual-luciferase reporter assay confirmed the direct interaction between miR-338-3p and the 3′-untranslated region of BAMBI messenger RNA. Furthermore, the suppression of BAMBI ameliorated the effect of miR-338-3p inhibition against ox-LDL-induced HUVEC cell injury. In conclusion, our study thus suggests that miR-338-3p promoted ox-LDL-induced HUVEC cell injury by targeting BAMBI and activating the TGF-β/Smad pathway, which may provide a novel and promising therapeutic target for AS.  相似文献   
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