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1.
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings.  相似文献   
2.
Extremely miniaturized longipedes insects (body length c. 0.3 mm) embedded in two pieces of Cretaceous amber from Myanmar are described and interpreted. Using inverted fluorescence and light microscopy for detailed analysis of microstructures, the inclusions were identified as primary larvae of the beetle family Ripiphoridae, subfamily Ripidiinae. While the structure of thoracic and abdominal segments including appendages corresponds well with the groundplan known in recent members of Ripidiinae, a curved prosternal ridge with prominent spines (each c. 5 μm), the reduced condition of stemmata and antennae and the lack of sharp mandibles are unique features within the entire family, apparently apomorphies of the longipedes larvae. A sinuate prosternal edge with a dense row of spines (prosternoctenidium) might be homologous with ‘head ctenidia’ in some previously described miniaturized conicocephalate larvae, but further investigation is needed. The morphological differences between the head of longipedes larvae and extant Ripidiinae are interpreted as adaptations to different groups of hosts and life strategies. Palaeoethology of the longipedes larvae is briefly discussed. In addition, the systematic placement of conicocephalate larvae from Canadian, Myanmar and Russian Cretaceous ambers, already interpreted by various authors as primary instars within Coleopterida (assigned to either Strepsiptera or to the coleopteran Tenebrionoidea: Ripiphoridae), is discussed.  相似文献   
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4.
Stbd1 is a protein of previously unknown function that is most prevalent in liver and muscle, the major sites for storage of the energy reserve glycogen. The protein is predicted to contain a hydrophobic N terminus and a C-terminal CBM20 glycan binding domain. Here, we show that Stbd1 binds to glycogen in vitro and that endogenous Stbd1 locates to perinuclear compartments in cultured mouse FL83B or Rat1 cells. When overexpressed in COSM9 cells, Stbd1 concentrated at enlarged perinuclear structures, co-localized with glycogen, the late endosomal/lysosomal marker LAMP1 and the autophagy protein GABARAPL1. Mutant Stbd1 lacking the N-terminal hydrophobic segment had a diffuse distribution throughout the cell. Point mutations in the CBM20 domain did not change the perinuclear localization of Stbd1, but glycogen was no longer concentrated in this compartment. Stable overexpression of glycogen synthase in Rat1WT4 cells resulted in accumulation of glycogen as massive perinuclear deposits, where a large fraction of the detectable Stbd1 co-localized. Starvation of Rat1WT4 cells for glucose resulted in dissipation of the massive glycogen stores into numerous and much smaller glycogen deposits that retained Stbd1. In vitro, in cells, and in animal models, Stbd1 consistently tracked with glycogen. We conclude that Stbd1 is involved in glycogen metabolism by binding to glycogen and anchoring it to membranes, thereby affecting its cellular localization and its intracellular trafficking to lysosomes.  相似文献   
5.
1983年,Lohka和Masui首先报道,用精子染色质与卵提取物一起温育,可以组装成具有典型结构的细胞核。这种核不仅具有合成DNA的能力,而且还能进入M期。同年,  相似文献   
6.
农业生态系统中新物种引进的初步探讨   总被引:5,自引:0,他引:5  
在现有的农业生态系统中,引进某些新物种,往往可以使整个系统的功能发生变化。如果新物种引进得当,则可产生良好的效果,系统功能得以改善,效益提高;反之,则会造成人力、物力、财力的损失,削弱系统的功能,甚至可能遗患无穷。因此,对农业生态系统中  相似文献   
7.
翟虎渠 《遗传学报》1990,17(1):6-12
在黄花烟草Nicotiana russica中,开花期这一性状用V_5作亲本可能产生较大变异,无论是选择早开花的还是选择迟开花的,都有较大机会得到理想目标株系;对于株高这一性状,含有V(?)的组合可望有较大机会产生高于标准品种的株系。通过组合间育种潜势的比较,能了解各亲本中基因分布的基本情况,进而进行客观评价并对杂交组合做出取舍。试验证明,用一个组合的早期世代的参数m和D来预测高世代或纯系的育种潜势是可行的。  相似文献   
8.
A tandemly repeated DNA sequence (RRS7) was isolated from Oryza alta (CCDD). RRS7-related sequences were also found tandemly arrayed in genomes AA, BB, BBCC, CC, and EE, and a small amount of RRS7-related sequences were detected in genome FF and the Oryza species with unknown genomes. DNA sequence analysis of the 1844-bp insert of RRS7 revealed that it contained six tandemly repeated units, of which five were 155 bp in length and one was 194 bp in length and contained an imperfect internal 39-bp duplication. Southern blot analysis showed that the boundary sequence contained in RRS7 is a single-copy sequence. A 155-bp consensus sequence derived from the six monomeric repeats contained no internal repeat and showed no significant homology to other currently known sequences. The results of Southern blot and sequence analysis revealed that there are at least two subfamilies present in the RRS7 family; these are represented by the DraI site and the MspI site, respectively. Restriction digestion with two pairs of isoschizomers MboI/Sau3A and MspI/HpaII demonstrated that most of the C residues in the GATC sites and the internal C in the CCGG sites of the RRS7 family in O. Alta were methylated. The usefulness of the RRS7 family in determining the evolutionary relationship of the genome DD and other Oryza genomes is discussed.  相似文献   
9.
长白山劲松林场植物群落的分类和排序   总被引:7,自引:2,他引:5  
将长白山白河林业局劲松林场的54块样地用聚类分析法划分成6个植被类群,再用PC-VTAB程序中经过改进的Braun-Blanquet学派的植被排表分析法进行综合,产生了鉴别概要表,为各个等级的植被类群筛选出诊断种。此外,还用鉴别种地样地记录进行主成分分析,以验证诊断种的有效性,结果表明,PC-VTAB中的植被排表分析法是筛选鉴别种的有效方法,而鉴别种以显著地提高植被分析和排序的质量。  相似文献   
10.
衣藻(Chlamydomonas sp)是属于绿藻门的最低等单细胞植物,为典型的真核生物。迄今以衣藻为材料所作的有关细胞骨架方面的研究多集中在微管蛋白(tubulin)。C.J.Miller等曾以衣藻(Chlamydomonas reinhardtii)全蛋白与几种中间纤维抗体进行免疫印迹实验有阳性反应,但是衣藻中是否存在中间纤维与核纤层是不清楚的问题。衣藻中间纤维与核纤层的形态研究更未见报道。目前认为中间纤维-核纤  相似文献   
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