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111.
目的:研究敲低P型磷酸果糖激酶(phosphofructokinase,PFKP)联合肉碱棕榈酰基转移酶抑制剂etomoxir对肾透明细胞癌Caki-1细胞的影响,并进一步探究其作用机制。方法:利用Western blot验证对照及PFKP shRNA敲低肾透明细胞癌细胞中PFKP的敲低效率,分别检测对照组(shCtrl)、PFKP敲低组、etomoxir组(shCtrl+etomoxir)、PFKP敲低联合etomoxir组的增殖曲线。使用Annexin-V/PI染色并用流式细胞检测对照组、PFKP敲低组、etomoxir组、PFKP敲低联合etomoxir组的细胞死亡,研究PFKP敲低联合etomoxir对细胞存活的影响。分别检测对照组、PFKP敲低组、etomoxir组、PFKP敲低联合etomoxir组的ATP水平与脂肪酸变化。结果:Western blot结果验证了PFKP的敲低效率。流式细胞检测显示,对照组、PFKP敲低组、etomoxir组、PFKP敲低联合etomoxir组的平均细胞死亡率分别为1.1、1.9、13.9、31.3%。PFKP敲低联合etomoxir组Caki-1细胞的死亡率显著高于单纯PFKP敲低与etomoxir组(P0.05)。PFKP敲低联合etomoxir组Caki-1细胞的ATP水平显著低于单纯PFKP敲低与etomoxir组(P0.05)。Etomoxir的加入抑制了PFKP敲低引起的游离脂肪酸下降(P0.05)。结论:PFKP敲低联合etomoxir对Caki-1细胞呈现协同的细胞毒抗肿瘤作用。  相似文献   
112.
为了探索金柑花发育的分子机制并研究与金柑花发育相关重要基因编码的蛋白质之间的相互作用,本研究以融安金柑不同生长时期的花蕾为材料,采用SMART技术构建了cDNA文库,对该文库进行了鉴定评价。经检测,所构建的cDNA文库滴度为2.83×10^8cfu/mL,文库库容为1.42×10^10cfu,重组率为97.91%,插入的双链cDNA片段长度主要分布在250~2 000 bp之间。结果表明,该文库达到了建库标准,理论上涵盖了全部与融安金柑花蕾发育相关的基因,为后续利用酵母双杂交技术筛选互作蛋白提供了物质基础。  相似文献   
113.
Yang  Gang  Wang  Huanyu  Feng  Mengyu  You  Lei  Zheng  Lianfang  Zhang  Taiping  Cong  Lin  Zhao  Yupei 《中国科学:生命科学英文版》2019,62(6):791-806
Pancreatic cancer is one of the most lethal human malignancies, partly because of its propensity for metastasis. However, highly metastatic human pancreatic cancer cell lines suitable for studies of metastasis are currently lacking. Here we established two highly metastatic human pancreatic cancer cell lines, MIA PaCa-2 In8 and Panc-1 In8, by Matrigel induction assay. The cell lines were further characterized both in vitro and in vivo. MIA PaCa-2 In8 and Panc-1 In8 cells demonstrated increased migration and invasion compared with their respective parental cells. Following injection into nude mice, MIA PaCa-2 In8 and Panc-1 In8 cells resulted in more pulmonary metastases compared with the parental cells. Furthermore, analyses of m RNA, long non-coding RNA, micro RNA, and methylation profiling revealed that these factors were aberrantly regulated in the highly metastatic cells,indicating that they probably affected metastasis. We thus established and characterized two highly metastatic human pancreatic cell lines that could be used as valuable tools for future investigations into the pathogenesis, metastasis, and potential treatment of human pancreatic cancer.  相似文献   
114.
Li  Guangwei  Jin  Jiye  Zhou  Yan  Bai  Xufeng  Mao  Donghai  Tan  Cong  Wang  Gongwei  Ouyang  Yidan 《中国科学:生命科学英文版》2019,62(4):507-516
Mendelian inheritance can ensure equal segregation of alleles from parents to offspring, which provides fundamental basis for genetics and molecular biology. Segregation distortion(SD) leads to preferential transmission of certain alleles from generation to generation. Such violation of Mendelian genetic principle is often accompanied by reproductive isolation and eventually speciation. Although SD is observed in a wide range of species from plants to animals, genome-wide dissection of such biased transmission of gametes is rare. Using nine inter-subspecific rice crosses, a genome-wide screen for SD loci is performed, which reveals 61 single-locus quantitative trait loci and 194 digenic interactions showing distorted transmission ratio, among which 24 new SD loci are identified. Biased transmission of alleles is observed in all nine crosses, suggesting that SD exists extensively in rice populations. 72.13% distorted regions are repeatedly detected in multiple populations, and the most prevalent SD hotspot that observed in eight populations is mapped to chromosome 3. Xian alleles are transmitted at higher frequencies than geng alleles in inter-subspecific crosses, which change the genetic composition of the rice populations. Epistatic interaction contributes significantly to the deviation of Mendelian segregation at the whole-genome level in rice, which is distinct from that in animals. These results provide an extensive archive for investigating the genetic basis of SD in rice, which have significant implications in understanding the reproductive isolation and formation of inter-subspecific barriers during the evolution.  相似文献   
115.
细胞自噬是真核生物在进化过程中高度保守、基于溶酶体的一种胞内降解途径,对维持细胞和生物体的稳态平衡有重要作用。研究表明,自噬参与生物体发育、免疫反应、代谢调节、细胞凋亡和衰老等多种过程。自噬功能异常与神经退行性疾病、肿瘤等的发生发展密切相关。近30年,我们对细胞自噬的认识无论是在分子机制上还是生理功能方面都有了长足的发展。为进一步加深对细胞自噬的认识,该文主要对细胞自噬的概念、自噬核心机器的组成及调控机制、自噬类型、生理功能及与疾病的关系作一简单综述。  相似文献   
116.
Initial functional studies have demonstrated that RNA‐binding motif protein 10 (RBM10) can promote apoptosis and suppress cell proliferation; however, the results of several studies suggest a tumour‐promoting role for RBM10. Herein, we assessed the involvement of RBM10 in lung adenocarcinoma cell proliferation and explored the potential molecular mechanism. We found that, both in vitro and in vivo, RBM10 overexpression suppresses lung adenocarcinoma cell proliferation, while its knockdown enhances cell proliferation. Using complementary DNA microarray analysis, we previously found that RBM10 overexpression induces significant down‐regulation of RAP1A expression. In this study, we have confirmed that RBM10 decreases the activation of RAP1 and found that EPAC stimulation and inhibition can abolish the effects of RBM10 knockdown and overexpression, respectively, and regulate cell growth. This effect of RBM10 on proliferation was independent of the MAPK/ERK and P38/MAPK signalling pathways. We found that RBM10 reduces the phosphorylation of CREB via the AKT signalling pathway, suggesting that RBM10 exhibits its effect on lung adenocarcinoma cell proliferation via the RAP1/AKT/CREB signalling pathway.  相似文献   
117.
118.
Conversion of CO2 to energy‐rich chemicals using renewable energy is of much interest to close the anthropogenic carbon cycle. However, the current photoelectrochemical systems are still far from being practically feasible. Here the successful demonstration of a continuous, energy efficient, and scalable solar‐driven CO2 reduction process based on earth‐abundant molybdenum disulfide (MoS2) catalyst, which works in synergy with an inexpensive hybrid electrolyte of choline chloride (a common food additive for livestock) and potassium hydroxide (KOH) is reported. The CO2 saturated hybrid electrolyte utilized in this study also acts as a buffer solution (pH ≈ 7.6) to adjust pH during the reactions. This study reveals that this system can efficiently convert CO2 to CO with solar‐to‐fuel and catalytic conversion efficiencies of 23% and 83%, respectively. Using density functional theory calculations, a new reaction mechanism in which the water molecules near the MoS2 cathode act as proton donors to facilitate the CO2 reduction process by MoS2 catalyst is proposed. This demonstration of a continuous, cost‐effective, and energy efficient solar driven CO2 conversion process is a key step toward the industrialization of this technology.  相似文献   
119.
Multi‐functional microRNAs (miRNAs) are emerging as key modulators of plant–pathogen interactions. Although the involvement of some miRNAs in plant–insect interactions has been revealed, the underlying mechanisms are still elusive. The brown planthopper (BPH) is the most notorious rice (Oryza sativa)‐specific insect that causes severe yield losses each year and requires urgent biological control. To reveal the miRNAs involved in rice–BPH interactions, we performed miRNA sequencing and identified BPH‐responsive OsmiR396. Sequestering OsmiR396 by overexpressing target mimicry (MIM396) in three genetic backgrounds indicated that OsmiR396 negatively regulated BPH resistance. Overexpression of one BPH‐responsive target gene of OsmiR396, growth regulating factor 8 (OsGRF8), showed resistance to BPH. Furthermore, the flavonoid contents increased in both the OsmiR396‐sequestered and the OsGRF8 overexpressing plants. By analysing 39 natural rice varieties, the elevated flavonoid contents were found to correlate with enhanced BPH resistance. Artificial applications of flavonoids to wild type (WT) plants also increased resistance to BPH. A BPH‐responsive flavanone 3‐hydroxylase (OsF3H) gene in the flavonoid biosynthetic pathway was proved to be directly regulated by OsGRF8. A genetic functional analysis of OsF3H revealed its positive role in mediating both the flavonoid contents and BPH resistance. And analysis of the genetic correlation between OsmiR396 and OsF3H showed that down‐regulation of OsF3H complemented the BPH resistance characteristic and simultaneously decreased the flavonoid contents of the MIM396 plants. Thus, we revealed a new BPH resistance mechanism mediated by the OsmiR396–OsGRF8–OsF3H–flavonoid pathway. Our study suggests potential applications of miRNAs in BPH resistance breeding.  相似文献   
120.
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