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1.
为了进一步研究甜菜谷胱甘肽转移酶BvGSTU9 (LOC104894060)在重金属胁迫过程中的功能。本研究以‘780016B/12优’为实验材料,对该基因序列特征、结构、功能进行预测分析,并利用qPCR检测该基因在不同浓度镉胁迫下的表达量变化。结果显示甜菜BvGSTU9基因全长925 bp,开放阅读框675 bp,编码了由224个氨基酸组成的不稳定膜外蛋白。BvGSTU9与菠菜、藜麦的氨基酸序列相似性较高,与系统发育进化树分析结果基本相符。二级和三级结构预测表明该基因主要由α-螺旋、β-折叠、延伸链及无规则卷曲组成。qPCR显示BvGSTU9基因在不同浓度的镉胁迫下均受到不同程度的诱导,因此可以推断甜菜BvGSTU9基因无论从结构还是功能上,与镉逆境胁迫存在着一定的应答关系。研究结果也为甜菜耐重金属镉机制研究提供参考依据。 相似文献
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CRISPR/cas是一种获得性免疫防御系统,广泛存在于细菌和古细菌中。Strep tococcus pyogenes cas9(Spcas9)作为目前研究最多、最清楚的效应蛋白,因其酶活性高和靶点广而被应用于生命科学各个领域,但Spcas9分子量大、脱靶率高等缺点在一定程度上限制了其应用。随着CRISPR系统技术被深入开发,一些新效应蛋白被发现,本文就CRISPR/cas系统分类、原理、新效应蛋白发现及cas9(S.Pyogenes)多种变构体技术开发在及家禽上的应用进行综述,为相关领域的研究提供参考。 相似文献
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ZHANG En-guang ZHANG Huai-qin LIN Jie HUANG Wei-jian LI Shang-gong XU Li-xin 《园艺学报》2003,19(5):653-656
AIM:To examine the relationship between the activity of matrix metallproteinases(MMPs) and ventricular remodeling following myocardial ischemia in the rat.METHODS:The model of myocardial ischemia(MI) in the rat was established by isoprenaline(ISP). The activity of MMPs was measured by zymography and collagen concentration was assessed by the method of chloramine T, so did I/III collagen ratio by immunohistochemical staining. The microstructure of myocardium was also observed by electron microscope.RESULTS:The activity of MMP-2 in myocardial ischemia group (group M) increased by 5.8 folds at 1 st week(P<0.01), 2.3 folds at 2 nd week(P<0.01) and 1.7 flods at 4 th week(P<0.05) compared with control group (group C) and MMP-9's activity in group M increased by 4.9 folds (P<0.01), 1.9 flods(P<0.01) and 1.4 folds(P<0.05), respectively. Collagen amount and I/III collagen ratio in group M increased compared with that in group C at 2 nd week and 4 th week. It showed that cardiac myocytes in group M were necrosed and collagen grew abundantly in interstitium under electron microscope.CONCLUSION:The activity of MMPs in the myocardial interstitium increased following myocardial ischemia, then collagen amount and I/III collagen ratio increased, which may be the major causes of ventricular remodeling. 相似文献
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Nitric oxide (NO) and matrix metalloproteinases (MMPs) are important in vascular remolding, especially in abdominal aortic aneurysm. NO may be associated with aneurysms by modulating MMPs expression and activity. 相似文献
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Chronic exposure to ultraviolet (UV) light promotes the breakdown of collagen in the skin and disrupts the extracellular matrix (ECM) structure, leading to skin wrinkling. Pacific whiting (Merluccius productus) is a fish abundant on the Pacific coast. In the current study, we investigated the anti-wrinkle effect of hydrolysate from Pacific whiting skin gelatin (PWG) in UVB-irradiated human dermal fibroblasts and the molecular mechanisms involved. PWG effectively restored type 1 procollagen synthesis reduced by UVB-irradiation. Also, we found that PWG inhibited collagen degradation by inhibiting MMP1 expression. Furthermore, PWG decreased cytokines TNF-α, IL-6, and IL-1β associated with inflammatory responses and increased antioxidant enzymes, HO-1, SOD, GPx, CAT, and GSH content, a defense system against oxidative stress. In terms of molecular mechanisms, PWG increased collagen synthesis through activating the transforming growth factor β (TGF-β)/Smad pathway and decreased collagen degradation through inhibiting the mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1) pathway. It also suppressed the inflammatory response through suppressing the nuclear factor-κB (NF-κB) pathway and increased antioxidant enzyme activity through activating the nuclear factor erythroid 2/heme oxygenase 1 (Nrf-2/HO-1) pathway. These multi-target mechanisms suggest that PWG may serve as an effective anti-photoaging material. 相似文献
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AIM To evaluate the effect of swimming on experimental endometriosis in rats. METHODS 80 female SD rats were divided into 8 groups, including control group, model group and animals performed light exercise (swimming once a week), moderate exercise (swimming 3 times a week), and intense exercise (swimming 5 times a week) before or after endometriosis induction,10 rats in each group. The mRNA and protein expressions of fatty acid synthase (FAS), matrix metalloproteinase 9 (MMP9) and proliferating cell nuclear antigen (PCNA) in endometrium of rats were detected. RESULTS The swimming before the induction of the edometriosis lesions did not prove to have aprophylactic role against endometriosis, whereas the swimming after induction of the lesions had a beneficial effect regardless of frequency, with a greater reduction in the groups practicing moderate and intense activity (P< 0. 05), an increase in FAS levels and a decrease in MMP9 and PCNA levels were also observed (P< 0. 05). CONCLUSION Swimming after induction of the edometriosis is beneficial for the treatment of endometriosis, the mechanism may be related to the expression of FAS, MMP9 and PCNA protein. 相似文献
10.
转基因小麦抗旱性鉴定及相关指标灰色关联度分析 总被引:1,自引:0,他引:1
以9份转ABP9基因春小麦株系UC4-1~UC4-9及其受体亲本宁春4号为材料,在雨养和灌溉条件下,对这些材料的主要农艺性状和部分生化指标进行了测定,采用隶属函数值法和抗旱性度量(D)值法对其抗旱性进行了综合评价,并利用灰色关联度法对相关抗旱性状与抗旱指数之间的关联度进行了分析评价。结果表明:6份转基因小麦的抗旱性较受体亲本宁春4号增强,3份材料的抗旱性较非转基因春小麦品种定西35增强;各农艺性状和生化指标与抗旱指数的关联度从高到低依次分别为株高、单穗粒重、穗长、SOD活性、穗粒数、结实小穗数、有效分蘖数、POD活性、千粒重、脯氨酸含量、MDA含量。 相似文献