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61.
葡萄糖-甲醇-胆碱氧化还原酶(glucose-methanol-choline oxidoreductases,GMC)家族是昆虫体内一大类以黄素腺嘌呤二核苷酸(FAD)为辅酶的氧化还原酶类,家蚕基因组中含有43个GMC家族基因。以家蚕5龄幼虫cDNA为模板克隆到一个家蚕GMC家族基因,命名为BmGMCβ2(GenBank登录号:JQ965926)。该基因cDNA全长1 875 bp,编码624个氨基酸,预测蛋白质分子质量为69.3 kD,pI为6.21,定位于家蚕16号染色体的nscaf3058上,编码蛋白质含GMC家族共有的ADP-bindingβ-α-β折叠结构域。系统发育分析表明该基因是家蚕GMC家族β亚家族基因成员。RT-PCR检测家蚕不同发育时期和5龄第3天幼虫不同组织中BmGMCβ2基因mRNA转录水平,以5龄盛食期最高,并且主要在表皮、脂肪体和气管中转录表达;Westernblotting分析BmGMCβ2蛋白主要在5龄第3天幼虫的脂肪体中表达。将BmGMCβ2克隆到原核表达载体pET-28a(+)中,转化E.coli BL21表达菌株,IPTG诱导表达BmGMCβ2融合蛋白,通过His-亲和层析得到纯化的融合蛋白并制备多克隆抗体,为后续研究该蛋白在家蚕生长发育过程中的功能奠定了基础。 相似文献
62.
为探究两广地区H9N2亚型禽流感病毒(avianinfluenzavirus,AIV)的变异情况及分子流行规律,于2011-2012年从该地区发病鸡群中共分离到16株H9N2亚型A1V,并对分离株HA基因进行测序与进化分析。结果表明,分离株HA基因开放阅读框全长均为1683bp,编码560个氨基酸;HA基因核苷酸同源性为88.7%~99.6%,编码氨基酸同源性为91.8%~99.5%。本试验分离毒株与国内疫苗株(GD-SS、SH—F和SD-6)的核苷酸同源性在90.1%~92.6%之间,推导的氨基酸序列同源性在91.6%~94.8%之间。进化分析显示分离株可分为Group1和Group2两个亚分支,与疫苗株均属于欧亚谱系的Y280分支,但亲缘关系较远。分离株HA蛋白裂解位点附近序列有3种形式:PARSSR+GLF、PSRSSR+GLF和PARLSR0GLF,均无连续碱性氨基酸的插A,符合低致病性AIv的特征。本试验发现分离株GD4、GX2在HA1的127、295位分别增加一个潜在的糖基化位点;除分离株GD5和GD6外,其余分离株在HAl的216位发生Q216L氨基酸突变,表明其存在感染人的可能性。 相似文献
63.
胰岛素样生长因子Ⅰ(IGF-Ⅰ)是胰岛素类激素家族中的成员之一,是一种在分子结构上与胰岛素类似的多肽蛋白物质.IGF-I在人体及动物体内具有极其重要并且丰富的生物学功能,如促生长、促分化、参与糖代谢、蛋白质代谢和脂肪代谢等,并对消化系统、泌乳及生殖有一定的影响.文章就IGF-I的来源,分子结构及生物学功能作一简单概述. 相似文献
64.
ASR蛋白与植物的抗逆性研究进展 总被引:1,自引:0,他引:1
ASR蛋白(the abscisic acid,stress,ripening protein)是生物体中广泛存在的一类与渗透调节有关的家族蛋白,植物受到逆境胁迫(如干旱、低温、盐胁迫、ABA等)后,ASR蛋白大量表达,可以减轻逆境引起的伤害。ASR蛋白在细胞中可以稳定细胞膜结构,作为分子伴侣,具有结合离子和防止氧化等作用,被认为是在胁迫过程中对植物起保护作用的物质之一。针对这些重要特性,综述了ASR蛋白分类、结构和编码基因及其表达调控方式及ASR基因表达、ASR蛋白积累与植物抗逆性的关系等方面的研究进展。 相似文献
65.
本研究克隆了二化螟(Chilo suppressalis)、台湾稻螟(Cauricilius)、芦苞螟(C.luteellus)、甘蔗条螟(C.sac-chariphagus)、三化螟(Tryporyza incertulas)、亚洲玉米螟(Ostrinia furnacalis)、甘蔗红尾白螟(Scirpophaga ex-cerptalis)、黄纹髓草螟(Calamotrophapaludella)、桃蛀螟(Conogethes puncti eralis)、棘禾草螟(Chilo hyrax)和稻蛀茎夜蛾(Sesamia in.erens)11种常见蛀茎害虫102个个体的线粒体DNA细胞色素氧化酶亚基Ⅰ(COⅠ)基因片段.序列分析显示:该COⅠ基因片段长为709 bp,序列都未发生缺失或插入现象,碱基颠换率(55.42%)高于转换率(44.58%);种间遗传距离平均值为0.140(0.088~0.179),种内遗传距离平均值为0.004(0~0.015),两者之间没有重叠区域;聚类分析表明,不同种蛀茎害虫分别形成独立的进化分支,分支自展值均为100%.研究结果表明该COⅠ基因序列具有适宜的变异信息,种内相对保守,种间变异显著,适用于蛀茎害虫的物种识别,并为开发蛀茎害虫DNA条形码技术奠定了基础. 相似文献
66.
YANG Yang XU Hou-qiang CHEN Wei ZHOU Di XU Min ZHANG Qing-qing ZHAO Huan-ping SUN Cheng-juan WANG Yuan-yuan ZHANG Ming YANG Tao 《中国畜牧兽医》2017,44(12):3401-3409
The objective of this study was to clone PDK4 and FGF10 genes, and investigate the expression level of PDK4 and FGF10 genes mRNA in different tissues of Large White pig and Congjiang Xiang pig. The PDK4 and FGF10 genes were cloned by RT-PCR and analyzed by bioinformatics, the relative expression of PDK4 and FGF10 genes were detected by Real-time PCR. The results showed that the coding region of PDK4 gene was 1 224 bp, encoding 407 amino acids; The coding region of FGF10 gene was 636 bp and encoded 211 amino acids. The homologies of nucleotide sequences of PDK4 gene with sheep, horse and human were 93%, 92% and 91%,respectively. The homologies of nucleotide sequences of FGF10 gene with sheep, cattle, human and mouse were 94%,93%, 93% and 90%, respectively. The phylogenetic tree of PDK4 gene showed that the genetic relationship of Congjiang Xiang pig, cattle and sheep were very close, the phylogenetic tree of FGF10 gene indicated that the genetic relationship of Congjiang Xiang pig, cattle, sheep, human and macaque were very close, but the genetic relationship of Congjiang Xiang pig, rat and chicken were far away. Real-time PCR results showed that, in different tissues of Congjiang Xiang pig,PDK4 gene expression in kidney tissue was higher than other tissues, with a higher expression in stomach and adipose as well,FGF10 gene expression in stomach tissue was higher than other tissues, with a higher expression in kidney and adipose as well, but both of PDK4 and FGF10 genes expression were the lowest in longissimus dorsi. In different tissues of Large White pig, both of PDK4 and FGF10 genes were expressed the highest in adipose than other tissues, PDK4 gene expression in longissimus dorsi was the lowest, while the FGF10 gene expression the lowest in heart. This study successfully cloned the PDK4 and FGF10 genes of Large White pig and Congjiang Xiang pig,and detected the relative expression of PDK4 and FGF10 genes in different tissues of Large White pig and Congjiang Xiang pig, and also provided scientific basis for further study on regulation of PDK4 and FGF10 genes on lipid metabolism and deposition. 相似文献
67.
为了解秦皇岛昌黎县狐和貉源致病性大肠埃希菌耐药性及耐药基因的情况,以昌黎县分离的15株狐和貉源致病性大肠埃希菌为试验菌株,采用药敏纸片法对抗菌药物进行药敏试验,并对四环素类耐药基因tetA、tetB、tetC、tetD,氨基糖苷类耐药基因strA-strB、aadA1,磺胺类耐药基因sul1、sul2、sul3进行PCR检测。结果显示,15株大肠埃希菌分离菌株对土霉素、多西环素、头孢拉定、新霉素、青霉素、磺胺间甲氧嘧啶、磺胺二甲氧嘧啶的耐药率均为100%;对阿莫西林、庆大霉素、头孢曲松、阿米卡星、大观霉素、链霉素、复方新诺明、氨苄西林、环丙沙星耐药率分别为93.33%、53.33%、33.33%、73.33%、86.66%、86.66%、86.66%、66.67%和66.67%。9种耐药基因tetA、tetB、tetC、tetD、strA-strB、aadA1、sul1、sul2、sul3的检出率分别为0、46.67%、26.67%、13.33%、40%、100%、53.33%、46.67%和53.33%,其中四环素类耐药基因以tetB的检出率最高,氨基糖苷类耐药基因以aadA1的检出率最高,磺胺类耐药基因的检出率相差不大。说明15株狐和貉源大肠埃希菌耐药谱广,耐药性高,耐药基因流行普遍。 相似文献
68.
LIU Cui-cui GUO Xiao-hong CAO Guo-qing GAO Peng-fei PU Zhong-de NIU Jiao-yan ZHANG Qi LI Meng JIN Yu-shu LI Bu-gao 《中国畜牧兽医》2015,42(10):2726-2731
The aim of this study was to investigate the developmental patterns of ApoCⅡ gene mRNA in liver in Mashen and Large White pigs, and study the relationship between the expression level of ApoCⅡ and the lipid metabolism in pigs.The mRNA relative expressions of ApoCⅡ gene in liver at seven stages of 1,30,60,90,120,150,and 180-day old in Mashen and Large White pigs were determined by quantitative Real-time PCR.The results showed that the developmental trend of ApoCⅡ mRNA expression in liver between Mashen and Large White pigs was different.The ApoCⅡ mRNA abundance was decreased from birth to 60-day old,then increased at 90-day old,and decreased again after that in Mashen pig.However,the relative expression amount in Large White pig was gradually decreased from birth to 150-day old and increased again at 180-day old.Except for the ApoCⅡ mRNA expression amount at 1-day old,the differences of the expression amount at other stages in Mashen and Large White pigs were significant or extremely significant (P<0.05 or P<0.01).The ApoCⅡ mRNA expression in liver was affected by age and breed,and could play an important role in lipid metabolism in pigs. 相似文献
69.
Identification of Neofabraea species causing bull's eye rot of apple in Poland and their direct detection in apple fruit using multiplex PCR 下载免费PDF全文
Based on partial sequence analysis of the β‐tubulin gene, 19 isolates of fungi causing bull's eye rot on apple in Poland were classified into species: Neofabraea alba, N. perennans and N. kienholzii. To the authors’ knowledge, the detection of N. kienholzii is the second in Europe and the first in Poland. Species affiliation of these fungi was confirmed by a new species‐specific multiplex PCR assay developed on the basis of previously published methods. The new protocol allowed for the specific identification of bull's eye rot‐causing species, both from pure cultures and directly from the skin of diseased or apparently healthy apples. In 550 samples of diseased fruits collected from nine cold storage rooms located in three regions of Poland, in 2011 and 2012, N. alba was detected as the predominant species causing bull's eye rot, occurring on average in 94% of the tested samples. Neofabraea perennans was found in a minority of apple samples, N. kienholzii was found only in two apple samples, while N. malicorticis was not detected in any sample tested. In tests on 120 apparently healthy fruits, only N. perennans was detected in a single sample. The results of genetic diversity analyses of bull's eye rot‐causing fungi based on the β‐tubulin gene sequence and an ISSR (inter‐simple sequence repeat) PCR assay with two primers were consistent, showing the expected segregation of tested isolates with respect to their species boundaries. However, the genetic distance between N. perennans and N. malicorticis was very low, as reported previously. 相似文献
70.