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11.
N-Acetylgalactosaminyltransferase-14 (GALNT14) is a member of acetylgalactosaminyltransferases family. We have shown that GALNT14 could promote breast cancer cell invasion. However, the underlying molecular mechanism is unclear. Here, using yeast two hybrid, we find that EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2) interacts with GALNT14. Both in vitro and in vivo binding assays show that EFEMP2 is associated with GALNT14. Moreover, we find that GALNT14 mediates glycosylation of EFEMP2. EFEMP2 significantly increased the invasion ability of breast cancer cells including MCF-7 and MBA-MD-231 cells, and this phenomenon is suppressed by knockdown expression of GALNT14. In addition, the GALNT14-dependent O-glycosylation of EFEMP-2 regulates the stability of EFEMP-2 protein in breast cancer cells. Taken together, our results demonstrate a novel molecular mechanism underlying breast cancer invasion.  相似文献   
12.
Previous studies proved that long noncoding RNAs (lncRNAs) play important role in human cancer. However, the knowledge of genome scale expression of lncRNAs and their potential biological function in gastric cancer is still lacking. Next generation RNA sequencing (RNA-seq) was performed on tumor tissues and matched adjacent normal tissues of six diffuse gastric cancer (DGC) patients. Then we performed a comprehensive analysis on lncRNAs and mRNA. Fifty-eight lncRNAs were upregulated and 54 lncRNAs were downregulated in diffuse gastric cancer tissue compared with adjacent tissue. The numbers of up- and downregulated mRNAs were 306 and 161, respectively. In addition, we inferred the function of lncRNAs by construction of a co-expression network for deregulated mRNAs and lncRNAs. Co-expressed genes of MEF2C-AS1 and FENDRR were enriched to RAS and TGF-beta signaling pathway. MEF2C-AS1 and FENDRR expression were re-evaluated by Real-time Quantitative PCR in 42 DGC patients' tumor and normal tissues, and other 46 DGC patents' and 21 healthy controls' plasma. Validation data showed MEF2C-AS1 and FENDRR were significantly downregulated in tumor tissues compared with normal tissues. And decreased FENDRR are associated with aggressive tumor characteristics including more advanced stage (P = .030), poor differentiation (P = .043) and lymphatic metastasis (P = .001). The expression level MEF2C-AS1 was significantly lower in DGC patients' plasma than that in healthy controls' plasma. In gastric cancer cell lines, knock-down of MEF2C-AS1 or FENDRR reduced the protein levels of FAT3, NTN1 and LYVE1 (the co-expressed genes), which were related with gastric cancer cell proliferation and invasion by previous studies. In addition, knock-down of MEF2C-AS1 or FENDRR promoted aggressive tumor behaviors in in-vitro assays. In this study, we provide a valuable resource of lncRNAs which might play important roles in the function of oncogenes or tumor suppressors affecting the development and progression of diffuse gastric cancer.  相似文献   
13.
镰形棘豆的一个新变型——白花镰形棘豆   总被引:2,自引:2,他引:0  
描述了豆科棘豆属镰形棘豆(Oxytropis falcata Bunge)的一个新变型:白花镰形棘豆(Oxytropis falcataBunge form.atbiflora Y.H.Wu).原变型的花冠为蓝紫色或紫红色,而新变型花冠为白色.  相似文献   
14.
杏属(蔷薇科)一新种   总被引:2,自引:0,他引:2  
发表了蔷薇科杏属的一个新种,即仙居杏(Armeniaca Xianjuxing J.Y.Zhang et Z.X.Wu),其与普通杏(Armeniaca vulgaris Lam.)的区别在于叶片两面具有短柔毛,花梗或果梗长1~1.2 cm,花瓣边缘钝锯齿或小裂片状,萼片边缘有小钝锯齿。  相似文献   
15.
标本采自湖南省永顺县万民乡志留系下部Llandovery统Telychian阶秀山组上部,几乎全部为Coronocephalus gaoluoensis Wu,其中有20多块头、胸、尾相连的完整标本。研究发现,Coronocephalus gaoluoensis Wu具有十分特殊的头部构造,其面线前支横切头鞍前叶中前部...  相似文献   
16.
1. Pan traps or water traps have been used widely to sample agricultural insect pests, but no formal studies have assessed the utility of these traps as sampling devices for bees. 2. Coloured pan traps, used as flower models, can efficiently and selectively sample an oligolectic bee, Andrena (Hesperandrena) limnanthis, and other bees associated with white-flowered Limnanthes douglasii rosea. 3. Females and males of A. limnanthis unexpectedly exhibit different colour preferences. Females are strongly attracted to white and blue traps, but discriminate against yellow traps. Males prefer white traps over blue and yellow traps. Consequently, blue traps are selective for females only, while white traps are selective for both sexes. 4. Non-A. limnanthis bees were caught in significantly greater numbers in yellow than in blue or white traps. These bees included generalists, as well as specialists that are oligolectic on mostly yellow-flowered species. 5. Colour of traps had a significant effect on the numbers of A. limnanthis females and males, and non-A. limnanthis bees caught in traps. These results indicate that quantitative sampling of bees by pan trap methods can be highly sensitive to trap colour.  相似文献   
17.
吴伟生  罗运祥 《植物研究》1992,12(1):123-124
本文发表了冬青属一新变种, 即短柄香冬青Ilex.suaveolens(Levl.)Loes.var.drevipetiola W.S.Wu et Y.X.Luo, var.nov.。  相似文献   
18.
酮(Xanthone)又称苯骈色原酮,是一类黄色或无色的酚性化合物,具有与黄酮类(Flavonoids)相似的颜色反应及色谱特性,因此曾被归入黄酮类讨论,但从其光谱特征看酮与黄酮是有区别的。 酮类主要分布于龙胆科(Gentianaceae)、藤黄科(Guttiferae)、桑科(Moraceae)和远志科(Polygalaceae)。但有一特殊例外:芒果甙(mangiferin-2-C-β-D-毗哺葡萄糖基-1,3,6,7-四羟基酮)不仅广布于被子植物的漆树科、藤黄科、豆科、山榄科、大风子科、百合科、鸢尾科、禾本科等,而且在蕨类植物的水龙骨科(Polypodiaceae)中也有发现。  相似文献   
19.
Currently, the habitat of many species is fragmented, resulting in small local populations with individuals occasionally dispersing between the remaining habitat patches. In a solitary bee metapopulation, extinction probability was related to both local bee population sizes and pollen resources measured as host plant population size. Patch size, on the other hand, had no additional predictive power. The turnover rate of local bee populations in 63 habitat patches over 4 years was high, with 72 extinction events and 31 colonization events, but the pollen plant population was stable with no extinctions or colonizations. Both pollen resources and bee populations had strong and independent effects on extinction probability, but connectivity was not of importance. Colonizations occurred more frequently within larger host plant populations. For metapopulation survival of the bee, large pollen plant populations are essential, independent of current bee population size.  相似文献   
20.
几种金花茶花粉的扫描电镜观察   总被引:8,自引:0,他引:8  
在扫描电镜下观察了我国广西原产的10种和3变种金花茶的花粉形态。其花粉外壁纹饰可分为三个类型。一、拟网纹饰:东兴金花茶、武鸣金花茶、(坛洛)金花茶、小果金花茶和陇瑞(玫瑰)金花茶。二、穴状纹饰:毛籽金花荼、(防城)金花茶和毛瓣金花茶。三、突起纹饰:小花金花茶、显脉金花茶,大样(?)岗金花茶、平果金花茶和山墟金花茶。在各个种及变种之间,花粉形态也存在一定的差异。  相似文献   
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