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51.
The article presents a simple expression of the power transferred from the electromagnetic field (EMF) to a biological nanomachine (NM) embedded in a background medium (BM). The expression is useful to analyse the interaction mechanism and test the hypothesis on its nature. Furthermore, it should represent a helpful tool to design remotely controlled NMs for bio-medical applications and the relative electromagnetic control apparatuses. Finally, to show its practical usefulness, we used it to discuss the hypothesis on the energy transfer mechanism proposed in the literature to explain intriguing experimental phenomena referring to the remotely controlled dehybridization of DNA molecules attached to gold nanocrystals. 相似文献
52.
Cardone RA Bagorda A Bellizzi A Busco G Guerra L Paradiso A Casavola V Zaccolo M Reshkin SJ 《Molecular biology of the cell》2005,16(7):3117-3127
Metastasis results from a sequence of selective events often involving interactions with elements of the tumor-specific physiological microenvironment. The low-serum component of this microenvironment confers increased motility and invasion in breast cancer cells by activating the Na+/H+ exchanger isoform 1 (NHE1). The present study was undertaken to characterize the signal transduction mechanisms underlying this serum deprivation-dependent activation of both the NHE1 and the concomitant invasive characteristics such as leading edge pseudopodia development and penetration of matrigel in breast cancer cell lines representing different stages of metastatic progression. Using pharmacological and genetic manipulation together with transport and kinase activity assays, we observe that the activation of the NHE1 and subsequent invasion by serum deprivation in metastatic human breast cells is coordinated by a sequential RhoA/p160ROCK/p38MAPK signaling pathway gated by direct protein kinase A phosphorylation and inhibition of RhoA. Fluorescence resonance energy transfer imaging of RhoA activity and immunofluorescence analysis of phospho-RhoA and NHE1 show that serum deprivation dynamically remodels the cell, forming long, leading edge pseudopodia and that this signal module is preferentially compartmentalized in these leading edge pseudopodia, suggesting a tight topographic relation of the signaling module to an invasion-specific cell structure. 相似文献
53.
Establishing a standard definition for child overweight and obesity worldwide: international survey 总被引:4,自引:0,他引:4
This study aimed to develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, reference population, and age and sex specific cut off points. Data on body mass index (weight/height) were obtained from 6 large nationally representative cross sectional surveys on growth from Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the US. The study included 97,876 males and 94,851 females from birth to 25 years of age. For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cut-off points of 25 and 30 kg/sq. m for adult weight and obesity. The resulting curves were averaged to provide age- and sex-specific cut-off points from 2 to 18 years. The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children. 相似文献
54.
Wang WM Ma XF Zhang Y Luo MC Wang GL Bellizzi M Xiong XY Xiao SY 《Molecular plant》2012,5(5):1125-1137
Many fungal and oomycete pathogens differentiate a feeding structure named the haustorium to extract nutrition from the plant epidermal cell. The atypical resistance (R) protein RPW8.2 activates salicylic acid (SA)-dependent, haustorium-targeted defenses against Golovinomyces spp., the causal agents of powdery mildew diseases on multiple plant species. How RPW8.2 activates defense remains uncharacterized. Here, we report that RPW8.2 interacts with the phytochrome-associated protein phosphatase type 2C (PAPP2C) in yeast and in planta as evidenced by co-immunoprecipitation and bimolecular fluorescence complementation assays. Down-regulation of PAPP2C by RNA interference (RNAi) in Col-0 plants lacking RPW8.2 leads to leaf spontaneous cell death and enhanced disease resistance to powdery mildew via the SA-dependent signaling pathway. Moreover, down-regulation of PAPP2C by RNAi in the RPW8.2 background results in strong HR-like cell death, which correlates with elevated RPW8.2 expression. We further demonstrate that hemagglutinin (HA)-tagged PAPP2C prepared from tobacco leaf cells transiently transformed with HA-PAPP2C possesses phosphatase activity. In addition, silencing a rice gene (Os04g0452000) homologous to PAPP2C also results in spontaneous cell death in rice. Combined, our results suggest that RPW8.2 is functionally connected with PAPP2C and that PAPP2C negatively regulates SA-dependent basal defense against powdery mildew in Arabidopsis. 相似文献
55.
Chan-Ho Park Songbiao Chen Gautam Shirsekar Bo Zhou Chang Hyun Khang Pattavipha Songkumarn Ahmed J. Afzal Yuese Ning Ruyi Wang Maria Bellizzi Barbara Valent Guo-Liang Wang 《The Plant cell》2012,24(11):4748-4762
Although the functions of a few effector proteins produced by bacterial and oomycete plant pathogens have been elucidated in recent years, information for the vast majority of pathogen effectors is still lacking, particularly for those of plant-pathogenic fungi. Here, we show that the avirulence effector AvrPiz-t from the rice blast fungus Magnaporthe oryzae preferentially accumulates in the specialized structure called the biotrophic interfacial complex and is then translocated into rice (Oryza sativa) cells. Ectopic expression of AvrPiz-t in transgenic rice suppresses the flg22- and chitin-induced generation of reactive oxygen species (ROS) and enhances susceptibility to M. oryzae, indicating that AvrPiz-t functions to suppress pathogen-associated molecular pattern (PAMP)-triggered immunity in rice. Interaction assays show that AvrPiz-t suppresses the ubiquitin ligase activity of the rice RING E3 ubiquitin ligase APIP6 and that, in return, APIP6 ubiquitinates AvrPiz-t in vitro. Interestingly, agroinfection assays reveal that AvrPiz-t and AvrPiz-t Interacting Protein 6 (APIP6) are both degraded when coexpressed in Nicotiana benthamiana. Silencing of APIP6 in transgenic rice leads to a significant reduction of flg22-induced ROS generation, suppression of defense-related gene expression, and enhanced susceptibility of rice plants to M. oryzae. Taken together, our results reveal a mechanism in which a fungal effector targets the host ubiquitin proteasome system for the suppression of PAMP-triggered immunity in plants. 相似文献
56.
L Pellegrini B Pucci L Villanova M L Marino G Marfe L Sansone E Vernucci D Bellizzi V Reali M Fini M A Russo M Tafani 《Cell death and differentiation》2012,19(11):1815-1825
Mitochondrial sirtuin 3 (SIRT3) mediates cellular resistance toward various forms of stress. Here, we show that in mammalian cells subjected to hypoxia and staurosporine treatment SIRT3 prevents loss of mitochondrial membrane potential (ΔΨmt), intracellular acidification and reactive oxygen species accumulation. Our results indicate that: (i) SIRT3 inhibits mitochondrial permeability transition and loss of membrane potential by preventing HKII binding to the mitochondria, (ii) SIRT3 increases catalytic activity of the mitochondrial carbonic anhydrase VB, thereby preventing intracellular acidification, Bax activation and apoptotic cell death. In conclusion we propose that, in mammalian cells, SIRT3 has a central role in connecting changes in ΔΨmt, intracellular pH and mitochondrial-regulated apoptotic pathways. 相似文献
57.
Nardis C Anzivino E Bellizzi A Rodio DM De Pità O Chiarini F Pietropaolo V 《Journal of cellular physiology》2012,227(12):3796-3802
Psoriasis vulgaris (PsV) and psoriatic arthritis (PSA) are inter‐related heritable inflammatory skin diseases. Psoriatic lesions develop as a result of abnormal immune responses, hyperproliferation and altered differentiation of keratinocytes, and a notable subset of psoriatic patients develops PsA, characterized by joints inflammation. Recently, biological drugs were introduced to treat these diseases. However, this therapy has already been associated with the development of serious life‐threatening infections, such as the reactivation of human polyomavirus JC (JCV), responsible for the progressive multifocal leukoencephalopathy (PML), a lethal demyelinating disease caused by oligodendrocytes lytic infection. Therefore, the aims of our study were the investigation of the possible JCV reactivation in PsV and PsA patients treated with adalimumab, etanercept, and methotrexate, performing quantitative real‐time PCR in sera and skin biopsies at the time of recruitment (T0) and after 3 (T3) and 6 (T6) months of treatment, and the sequencing analysis of the JCV non‐coding control region (NCCR). We found JCV DNA in 5/15 PsV patients and in 2/15 PsA patients and JCV NCCR sequence analysis always showed a structure similar to non‐pathogenic CY archetype, with random occurrence of a few irrelevant point mutations. Nevertheless the poor number of patients analyzed, our preliminary data can pave the way for taking into account that the follow‐up of JCV DNA detection and the JCV NCCR sequence analysis in psoriatic patients may be important to evaluate the risk of PML onset, considering that patients affected by autoimmune diseases and treated with biologics continue to rise. J. Cell. Physiol. 227: 3796–3802, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
58.
Dina Bellizzi Giuseppina Covello Fausta Di Cianni Qiang Tong Giovanna De Benedictis 《Molecules and cells》2009,28(2):87-92
Human SIRT3 gene contains an intronic VNTR enhancer. A T > C transition occurring in the second repeat of each VNTR allele implies the
presence/absence of a putative GATA binding motif. A partially overlapping AP-1 site, not affected by the transition, was
also identified. Aims of the present study were: 1) to verify if GATA and AP-1 sites could bind GATA2 and c-Jun/c-Fos factors,
respectively; 2) to investigate whether such sites modulate the enhancer activity of the SIRT3-VNTR alleles. DAPA assay proved that GATA2 and c-Jun/c-Fos factors are able to bind the corresponding sites. Moreover, co-transfection
experiments showed that the over-expression of GATA2 and c-Jun/c-Fos factors boosts the VNTR enhancer activity in an allelic-specific
way. Furthermore, we established that GATA2 and c-Jun/c-Fos act additively in modulating the SIRT3-VNTR enhancer function. Therefore, GATA2 and AP-1 are functional sites and the T S> C transition of the second VNTR repeat
affects their activity. 相似文献
59.
60.
Chan Ho Park Gautam Shirsekar Maria Bellizzi Songbiao Chen Pattavipha Songkumarn Xin Xie Xuetao Shi Yuese Ning Bo Zhou Pavinee Suttiviriya Mo Wang Kenji Umemura Guo-Liang Wang 《PLoS pathogens》2016,12(3)
Although nucleotide-binding domain, leucine-rich repeat (NLR) proteins are the major immune receptors in plants, the mechanism that controls their activation and immune signaling remains elusive. Here, we report that the avirulence effector AvrPiz-t from Magnaporthe oryzae targets the rice E3 ligase APIP10 for degradation, but that APIP10, in return, ubiquitinates AvrPiz-t and thereby causes its degradation. Silencing of APIP10 in the non-Piz-t background compromises the basal defense against M. oryzae. Conversely, silencing of APIP10 in the Piz-t background causes cell death, significant accumulation of Piz-t, and enhanced resistance to M. oryzae, suggesting that APIP10 is a negative regulator of Piz-t. We show that APIP10 promotes degradation of Piz-t via the 26S proteasome system. Furthermore, we demonstrate that AvrPiz-t stabilizes Piz-t during M. oryzae infection. Together, our results show that APIP10 is a novel E3 ligase that functionally connects the fungal effector AvrPiz-t to its NLR receptor Piz-t in rice. 相似文献