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991.
本研究旨在揭示肌抑素(MSTN)与基质金属蛋白酶(MMPs)的调控关系,探明MSTN对PK15细胞MMP-2/7/9表达的影响。对MSTN单等位基因敲除猪背膘组织进行转录组测序分析,复苏前期制备的MSTN基因敲除PK15细胞系:单等位基因敲除的PK3108细胞系和双等位基因敲除的L18细胞系,通过实时荧光定量PCR和Wesrern blotting分别检测PK15、PK3108和L18细胞系中MSTN、MMP-2/7/9基因的mRNA和蛋白表达水平。结果发现,与野生型猪相比,MSTN单等位基因敲除猪背膘组织转录因子C/EBPδ、MMP-2/7基因mRNA表达量均极显著下调(P < 0.01);细胞外基质中纤连蛋白(FN)和层连接蛋白(LN)含量均极显著增加(P < 0.01)。复苏的PK3108和L18细胞呈现绿色荧光。实时荧光定量PCR结果显示,PK3108和L18细胞中MSTN、MMP-2/7/9的mRNA表达量均极显著低于PK15细胞(P < 0.01);Western blotting结果显示,PK3108和L18细胞中MSTN、MMP-2/7/9的蛋白表达量均明显低于PK15细胞。本研究结果表明,在MSTN基因敲除的PK15细胞中,MSTN功能缺失能显著降低MMP-2/7/9的表达,且MMP-2/7/9蛋白表达降低的趋势与MSTN蛋白表达的趋势相一致。 相似文献
992.
We collected data on habitat use and locomotion of the François' langur (Trachypithecus francoisi) between August 2003 and July 2004 at Nonggang Nature Reserve, China. A total of 739 h of behavioral data were collected during this study. We tested 2 predictions: (1) that the langurs may have special patterns of habitat use and locomotion adaptive to the limestone habitat, and (2) the langurs may exhibit different patterns of habitat use and locomotion among different zones of limestone hill. Our results indicated that François– langurs spent more time in the low‐risk, relatively food‐poor cliff–hilltop areas. When young leaves and fruit were scarce in the dry season, the langurs increased their time in the high‐risk, food‐rich valley basin. François– langurs were semi‐terrestrial, and leaping and climbing were their main locomotor modes. These behavioral patterns are considered to be related to characteristics of topography and vegetation in limestone habitat, such as large areas of cliff and discontinuous canopy. Our results also supported Prediction 2. The langurs confined locomotion to the main canopy and frequently adopted leaping while traveling in the hillside and valley basin. While traveling in cliff–hilltop areas, they tended to stay in the lower stratus (≤5 m) or move on the ground, and walking and climbing were their dominant traveling modes. 相似文献
993.
采用RT-PCR扩增了国内H7N2禽流感病毒(AIV)CK/HB/1/02分离株的完整神经氨酸酶(NA)基因节段,测定了其核苷酸序列,并与GenBank中AIV NA基因序列进行了同源性比较和氨基酸编码分析,绘制了NA基因的系统发育进化树。结果表明,AIVCK/HB/1/02分离株NA基因的完整序列长度为1467bp,包括5′-末端和3′-末端的非编码区,其最大阅读框(ORF)编码469个氨基酸,第61~65位氨基酸序列为-NITGI-,不同于国内H9N2AIV的特殊遗传标记。该病毒NA基因的核苷酸序列与GenBank中人类流感病毒A/Leningrad/134/57(H2N2)的NA基因同源性最高,为93.3%;其次为香港的鸭源、人源、猪源H3N2病毒(89%~93%);而与我国北京、广东、香港和韩国的H9N2AIV以及美国的H7N2AIV的同源性较低(85%~88%)。在N2基因系统发育进化树中,CK/HB/1/02分离株处于欧亚分支内,与H2N2人流感病毒的亲缘关系较近;与北美H7N2AIV处在不同分支,遗传距离较远。 相似文献
994.
为实现家兔BMP7基因原核表达及探索适宜的表达条件,采用PCR技术从pMD18-T-BMP7重组质粒中扩增获得BMP7基因成熟肽片段(mBMP7),构建原核表达工程菌pET32a-mBMP7/BL21(DE3)和pET32a-mBMP7/BL21(DE3)pLysS,并比较温度、IPTG浓度、诱导时间等因素对目的蛋白表达的影响。结果表明,mBMP7原核表达载体构建正确;工程菌pET32a-mBMP7/BL21(DE3)和pET32a-mBMP7/BL21(DE3)pLysS经IPTG诱导均可表达含有家兔BMP7成熟肽的34KDa的融合蛋白,表达产物约占菌体总蛋白的30%。在37℃、0.75 mM IPTG以及诱导150 min时,能取得较高的目的蛋白表达量;在20℃低温条件下,IPTG浓度和诱导表达时间应分别以0.20 mM和7 h为宜;另外,目的蛋白表达对工程菌生长无明显的不利影响。因此,成功地构建了家兔BMP7基因工程菌,并确定了适宜的表达条件,为进一步研究该蛋白的结构和功能奠定基础。 相似文献
995.
996.
CHEN Yu LI Zhen-ye ZHANG Xiang-heng XIANG Jin SAI Ke KE Chao YANG Qun-ying GUO Jian-gui CHEN Zhong-ping MOU Yong-gao 《园艺学报》2013,29(5):810-814
AIM: To investigate the expression of B7-H4 in human glioma tissues and its clinical significance. METHODS: The histological staging of 150 cases of human glioma tissues was determined by HE staining. Immunohistochemistry was performed to study the protein level of B7-H4 in 150 human glioma specimens. Furthermore, the relationships between the expression level of B7-H4 and clinicopathological parameters, as well as patients survival rate, were analyzed. RESULTS: HE staining result indicated that there were 12 cases staged as stage I, 50 cases stage II, 39 cases stage III and 49 cases stage IV in 150 glioma specimens. Ninety-seven cases highly expressed B7-H4 in total 150 glioma samples with a 64.7% high expression rate. The histological grade of the tissues with high B7-H4 expression was mostly III~IV. There were 53 cases with low B7-H4 expression in the total 150 glioma patients with a 35.3% low expression rate. The histological grade of the tissues with low B7-H4 expression was mostly I~II. The B7-H4 expression was related to the age of the patients (P<0.01) and the pathological grade of glioma (P<0.01), but not related to the location of glioma (P>0.05). Kaplan-Meier survival curves demonstrated that increased B7-H4 expression was associated with shorter overall survival time (P<0.01). Multivariate Cox regression analysis revealed that B7-H4, age, sex and pathological grade were independent prognostic factors in glioma patients. CONCLUSION: B7-H4 is expressed in most of glioma tissues. B7-H4 may be a novel prognostic biomarker and a new target of molecular therapy for gliomas. 相似文献
997.
采用台盼蓝法研究了桔黄裸伞的乙醚提取物、乙醇提取物和液体培养的菌丝及培养液的混合物对人乳腺癌细胞(MCF-7)的存活率和对其DNA合成的影响。结果表明:乙醇提取物对MCF-7细胞存活的抑制率达到100%。乙醇提取物和液体培养的菌丝及培养液的混合物对MCF-7细胞的DNA合成有较强的抑制作用,抑制率均达到96%以上。 相似文献
998.
从T7噬菌体培养液中粗提噬菌体颗粒,经热裂解后用苯酚、氯仿抽提进而获得纯净的T7噬菌体DNA。用PCR、酶切法鉴定T7噬菌体DNA的完整性。通过对不同感受态细菌浓度、T7噬菌体DNA用量、电转化电压条件的优化,建立了T7噬菌体反向遗传拯救方法。结果显示,提取的DNA结构完整,能够被特异性酶切割,多克隆位点序列正确。T7噬菌体的反向遗传拯救方法最优化条件为200 ng T7噬菌体DNA、1 ml 5×109感受态细菌、1.5 kV电转化电压,在此条件下获得的拯救效率为3.5×105 PFU/ng(DNA)。 相似文献
999.
Yoshihiro WAKAYAMA Satoshi HIRAKO Hirokazu OHTAKI Satoru ARATA Takahiro JIMI Kazuho HONDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1155
The aim of this study is to examine 1) muscle fiber type composition, 2) myofiber diameter, and 3) aquaporin (AQP) 7 and AQP 9 mRNA expressions by quantitative PCR in muscles of obese db/db mice. The myofiber type composition of skeletal muscle was not statistically significantly different between db/db mice and control mice; while the average myofiber diameter ratio showed a decrease in db/db mice. The expression of AQP7 but not AQP9 mRNA in the skeletal and cardiac muscles was significantly upregulated in db/db mice. Thus this study revealed quantitatively that type 2 myofiber atrophy was shown in the skeletal muscles of db/db mice. AQP7 mRNA expression was upregulated in the skeletal and cardiac muscles of db/db mice. 相似文献
1000.
Exploring novel candidate genes from the Mouse Genome Informatics database: Potential implications for avian migration research 下载免费PDF全文
To search for genes associated with migratory phenotypes in songbirds, we selected candidate genes through annotations from the Mouse Genome Informatics database and assembled an extensive candidate‐gene library. Then, we implemented a next‐generation sequencing approach to obtain DNA sequences from the Painted Bunting genome. We focused on those sequences that were conserved across avian species and that aligned with candidate genes in our mouse library. We genotyped short sequence repeats from the following candidate genes: ADRA1d, ANKRD17, CISH and MYH7. We studied the possible correlations between allelic variations occurring in these novel candidate migration genes and avian migratory phenotypes available from the published literature. We found that allele variation at MYH7 correlated with a calculated index of speed of migration (km/day) across 11 species of songbirds. We highlight the potential of the Mouse Genome Informatics database in providing new candidate genes that might play a crucial role in regulating migration in birds and possibly in other taxa. Our research effort shows the benefits and limitations of working with extensive genomic datasets and offers a snapshot of the challenges related to cross‐species validation in behavioral and molecular ecology studies. 相似文献