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31.
32.
Hjerpe R Thomas Y Chen J Zemla A Curran S Shpiro N Dick LR Kurz T 《The Biochemical journal》2012,441(3):927-936
Ubiquitin and UBL (ubiquitin-like) modifiers are small proteins that covalently modify other proteins to alter their properties or behaviours. Ubiquitin modification (ubiquitylation) targets many substrates, often leading to their proteasomal degradation. NEDD8 (neural-precursor-cell-expressed developmentally down-regulated 8) is the UBL most closely related to ubiquitin, and its best-studied role is the activation of CRLs (cullin-RING ubiquitin ligases) by its conjugation to a conserved C-terminal lysine residue on cullin proteins. The attachment of UBLs requires three UBL-specific enzymes, termed E1, E2 and E3, which are usually well insulated from parallel UBL pathways. In the present study, we report a new mode of NEDD8 conjugation (NEDDylation) whereby the UBL NEDD8 is linked to proteins by ubiquitin enzymes in vivo. We found that this atypical NEDDylation is independent of classical NEDD8 enzymes, conserved from yeast to mammals, and triggered by an increase in the NEDD8 to ubiquitin ratio. In cells, NEDD8 overexpression leads to this type of NEDDylation by increasing the concentration of NEDD8, whereas proteasome inhibition has the same effect by depleting free ubiquitin. We show that bortezomib, a proteasome inhibitor used in cancer therapy, triggers atypical NEDDylation in tissue culture, which suggests that a similar process may occur in patients receiving this treatment. 相似文献
33.
Gloushankova NA Wakatsuki T Troyanovsky RB Elson E Troyanovsky SM 《Cell and tissue research》2003,314(3):399-410
Subclones of human carcinoma-derived A-431 cell line stably producing fusion proteins consisting of the enhanced green fluorescent protein and either human desmoglein 2 (Dsg-GFP) or human plakoglobin (GFP-Pg) were used to examine the behavior of desmosomes in living cells. Immunofluorescence microscopy of the fixed cells showed that both fusion proteins, which were expressed in significantly lower levels relative to their endogenous counterparts, were efficiently recruited into desmosomes. Time-lapse confocal imaging of these cells reveals that such GFP-labeled desmosomes (GFP desmosomes) are stable structures which exhibit various dynamic and motile activities. The most notable are independent lateral mobility and fusion. Furthermore, the continual assembly of new nascent desmosomes is observed within stable contacts located at the middle of the epithelial sheet. A new GFP desmosome appears as a closely apposed group of fine patches which after a few minutes aggregate into a single structure. These three dynamic processes resulted in constant changes of desmosome distribution, numbers, and sizes. In addition, fluorescence recovery after photobleaching experiments showed that fine patches of desmosomal proteins may participate in desmosome maintenance. Such a diverse range of dynamic activities of desmosomes apparently produces flexible but tight cell-cell adhesion required for different morphogenetic events in epithelial structures.This work was supported by grant AR44016-04 from the National Institutes of Health 相似文献
34.
Zhiqiang?GaoEmail author Hong?Xie Yuan?Hong?Yu Natalia?C.?Tansil 《NanoBioTechnology》2005,1(3):283-285
We have developed ultrasensitive nucleic acid detection systems involving an amplification step where the analytical signal
correlates directly to the amount of nucleic acid in the solution So far, we have performed nucleic acid quantification on
several breast cancer susceptibility genes and were able to detect nucleic acid amounts that ranged from 0.1–1.0 fg of nucleic
acid, which is at least 1000 times more sensitive than conventional fluorescent detection methods. The biosensors are so sensitive
that they can be used for direct detection of breast cancer susceptibility genes in mRNA without involving a PCR step. 相似文献
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36.
Natalia Buitron 《The journal of the Royal Anthropological Institute》2020,26(1):48-66
In Amazonian societies, autonomy is said to be a core value motivating egalitarian politics. This article shows how the quest for autonomy and productiveness presently sets in motion processes that encroach upon these very values. Among the Shuar of Amazonian Ecuador, the realization of autonomy and productiveness increasingly depends on the capture of state resources. Shuar interact with the local state as members of relatively recent sedentary communities and through the mediation of elected leaders. In these processes, ‘community’ itself is transformed: being a channel to regenerate domestic livelihoods, it also becomes an end in itself, giving rise to new economistic attitudes while legitimizing inequalities between commoners and leaders. The article suggests that the pursuit of autonomy and productiveness within a process of village formation is central to the transformation of egalitarianism that occurs when small-scale Amazonian polities engage with nation-state politics. 相似文献
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Parental care involves elaborate behavioural interactions between parents and their offspring, with offspring stimulating their parents via begging to provision resources. Thus, begging has direct fitness benefits as it enhances offspring growth and survival. It is nevertheless subject to a complex evolutionary trajectory, because begging may serve as a means for the offspring to manipulate parents in the context of evolutionary conflicts of interest. Furthermore, it has been hypothesized that begging is coadapted and potentially genetically correlated with parental care traits as a result of social selection. Further experiments on the causal processes that shape the evolution of begging are therefore essential. We applied bidirectional artificial selection on begging behaviour, using canaries (Serinus canaria) as a model species. We measured the response to selection, the consequences for offspring development, changes in parental care traits, here the rate of parental provisioning, as well as the effects on reproductive success. After three generations of selection, offspring differed in begging behaviour according to our artificial selection regime: nestlings of the high begging line begged significantly more than nestlings of the low begging line. Intriguingly, begging less benefitted the nestlings, as reflected by on average significantly higher growth rates, and increased reproductive success in terms of a higher number of fledglings in the low selected line. Begging could thus represent an exaggerated trait, possibly because parent–offspring conflict enhanced the selection on begging. We did not find evidence that we co‐selected on parental provisioning, which may be due to the lack of power, but may also suggest that the evolution of begging is probably not constrained by a genetic correlation between parental provisioning and offspring begging. 相似文献
39.
Natalia Barbieri Susana Salva Matas Herrera Julio Villena Susana Alvarez 《Probiotics and antimicrobial proteins》2020,12(2):494-504
The effect of Lactobacillus rhamnosus CRL1505 (Lr) on macrophages (Ma) and dendritic cells (DC) in the orchestration of anti-pneumococcal immunity was stud 相似文献
40.
Ailec Ho‐Plagaro Concepcin Santiago‐Fernandez Cristina Rodríguez‐Díaz Carlos Lopez‐Gmez Sara Garcia‐Serrano Francisca Rodríguez‐Pacheco Sergio Valdes Alberto Rodríguez‐Caete Guillermo Alcaín‐Martínez Natalia Ruiz‐Santana Luis Vzquez‐Pedreo Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2020,28(9):1708-1717