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61.
Fatty acyl reductases (FARs) are key enzymes that participate in sex pheromone biosynthesis by reducing fatty acids to fatty alcohols. Lepidoptera typically harbor numerous FAR gene family members. Although FAR genes are involved in the biosynthesis of sex pheromones in moths, the key FAR gene of Spodoptera litura remains unclear. In this work, we predicted 30 FAR genes from the S. litura genome and identified a domain duplication within gene SlitFAR3, which exhibited high and preferential expression in the sexually mature female pheromone glands (PGs) and a rhythmic expression pattern during the scotophase of sex pheromone production. The molecular docking of SlitFAR3, as predicted using a 3D model, revealed a co-factor NADPH binding cavity and 2 substrate binding cavities. Functional expression in yeast cells combined with comprehensive gas chromatography indicated that the SlitFAR3 gene could produce fatty alcohol products. This study is the first to focus on the special phenomenon of FAR domain duplication, which will advance our understanding of biosynthesis-related genes from the perspective of evolutionary biology.  相似文献   
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Zhang G  Wang Y  Zhang Y  Wan X  Li J  Liu K  Wang F  Liu K  Liu Q  Yang C  Yu P  Huang Y  Wang S  Jiang P  Qu Z  Luan J  Duan H  Zhang L  Hou A  Jin S  Hsieh TC  Wu E 《Current molecular medicine》2012,12(2):163-176
The purpose of this study was to test the hypothesis that administration of epigallocatechin-3-gallate (EGCG), a polyphenol present in abundance in widely consumed tea, inhibits cell proliferation, invasion, and angiogenesis in breast cancer patients. EGCG in 400 mg capsules was orally administered three times daily to breast cancer patients undergoing treatment with radiotherapy. Parameters related to cell proliferation, invasion, and angiogenesis were analyzed while blood samples were collected at different time points to determine efficacy of the EGCG treatment. Compared to patients who received radiotherapy alone, those given radiotherapy plus EGCG for an extended time period (two to eight weeks) showed significantly lower serum levels of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and reduced activation of metalloproteinase-9 and metalloproteinase-2 (MMP9/MMP2). Addition of sera obtained from patients treated with combination of radiotherapy and EGCG feeding for 2-8 weeks to in vitro cultures of highly-metastatic human MDA-MB-231 breast cancer cells resulted in the following significant changes: (1) suppression of cell proliferation and invasion; (2) arrest of cell cycles at the G0/G1 phase; (3) reduction of activation of MMP9/MMP2, expressions of Bcl-2/Bax, c-Met receptor, NF-κB, and the phosphorylation of Akt. MDA-MB-231 cells exposed to 5-10 μM EGCG also showed significant augmentation of the apoptosis inducing effects of γ-radiation, concomitant with reduced NF-κB protein level and AKT phosphorylation. These results provide hitherto unreported evidence that EGCG potentiated efficacy of radiotherapy in breast cancer patients, and raise the possibility that this tea polyphenol has potential to be a therapeutic adjuvant against human metastatic breast cancer.  相似文献   
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Ovarian cancer (OC) is ranked the first among the cancers threatening women's health. It attracts tremendous attention of cancer researchers because of its extremely high mortality rate. Recent studies have indicated that traditional herbal medicines (THMs) can play a pivotal role in cancer prevention and treatment. THMs are gaining popularity as a source of anti‐cancer agents. The plant of Balanophora polyandra, which has been used as a traditional herbal medicine, has been known for exhibiting potential haemostatic, analgesic, anti‐inflammatory and anti‐cancer properties. However, few studies on inhibitory effect of B. polyandra on OC have been performed. In the present study, we found that B. polyandra polysaccharides (BPP) induced cell cycle arrest at S phase, triggered apoptosis and inhibited migration and invasion of OC cells. Furthermore, we also found that there was a potential and close relationship between BPP and P53‐mediated pathway. Overall, these findings suggest that BPP can be a potential therapeutic agent for the treatment of OC.  相似文献   
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Dispersal is a key life‐history trait governing the response of individuals, populations and species to changing environmental conditions. In the context of global change, it is therefore essential to better understand the respective role of condition‐, phenotype‐ and genetic‐dependent drivers of dispersal behaviour. Although the importance of immune function and pathogen infestation in determining patterns of dispersal is increasingly recognised, no study to our knowledge has yet investigated the influence of immune gene variability on dispersal behaviour. Here, we filled this knowledge gap by assessing whether individual heterozygosity at five immune gene loci (one from the Major histocompatibility complex and four from encoding Toll‐like receptors) influences roe deer natal dispersal. We found that dispersal propensity was affected by immune gene diversity, suggesting potential pathogen‐mediated selection through over‐dominance. However, the direction of this effect differed between high and low quality individuals, suggesting that dispersal propensity is driven by two different mechanisms. In support of the condition‐dependent dispersal hypothesis, dispersal propensity increased with increasing body mass and, among high quality individuals only (standardized body mass > 18 kg), with increasing immune gene diversity. However, among poor quality individuals, we observed the opposite pattern such that dispersal propensity was higher for individuals with lower immune gene diversity. We suggest that these poor quality individuals expressed an emergency dispersal tactic in an attempt to escape a heavily infested environment associated with poor fitness prospects. Our results have potentially important consequences in terms of population genetics and demography, as well as host–pathogen evolution.  相似文献   
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Fu H  Chen H  Zhang X  Qu Y  Marko JF  Yan J 《Nucleic acids research》2011,39(8):3473-3481
Recent studies have revealed two distinct pathways for the DNA overstretching transition near 65 pN: 'unpeeling' of one strand from the other, and a transition from B-DNA to an elongated double-stranded 'S-DNA' form. However, basic questions concerning the dynamics of these transitions, relative stability of the two competing overstretched states, and effects of nicks and free DNA ends on overstretching, remain open. In this study we report that: (i) stepwise extension changes caused by sequence-defined barriers occur during the strand-unpeeling transition, whereas rapid, sequence-independent extension fluctuations occur during the B to S transition; (ii) the secondary transition that often occurs following the overstretching transition is strand-unpeeling, during which the extension increases by 0.01-0.02 nm per base pair of S-DNA converted to single-stranded DNA at forces between 75 and 110 pN; (iii) even in the presence of nicks or free ends, S-DNA can be stable under physiological solution conditions; (iv) distribution of small GC-rich islands in a large DNA plays a key role in determining the transition pathways; and (v) in the absence of nicks or free ends, torsion-unconstrained DNA undergoes the overstretching transition via creation of S-DNA. Our study provides a new, high-resolution understanding of the competition between unpeeling and formation of S-DNA.  相似文献   
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甘蓝型油菜秦优10号杂交种纯度鉴定的SSR引物筛选   总被引:1,自引:0,他引:1  
为了建立一套快速可靠的油菜杂交种纯度的鉴定方法,本文以秦优10号及其亲本、杂种ZZH2为试验材料,对前人开发的2对SSR引物(7号引物, 9号引物)进行了再次筛选.结果显示,7号引物不但能很好地区别出混入杂交种中的亲本,还能将杂交种子的同母异父组合种子从杂交种中分离出来,能够用于鉴别秦优10号杂交种子的真伪;9号引物能区分出杂交种和母本,但不能区分开杂交种和父本.同时,本试验利用人工制成的秦优10号杂交种标准样(纯度为100%)以及7份大田鉴定不同纯度梯度的杂交种子对7号引物鉴定结果的准确性进行了验证,鉴定结果与大田鉴定结果基本一致.本文结果将为鉴定秦优10号杂交种纯度提供更准确的技术资料.  相似文献   
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