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991.
Protein serine/threonine kinase casein kinase 2 (CK2) is a key player in cell growth and proliferation but is also a potent suppressor of apoptosis. CK2 has been found to be dysregulated in all the cancers that have been examined, including prostate cancer. Investigations of CK2 signaling in the prostate were originally initiated in this laboratory, and these studies have identified significant functional activities of CK2 in relation to normal prostate growth and to the pathobiology of androgen-dependent and -independent prostate cancer. We present a brief overview of these developments in the context of prostate biology. An important outcome of these studies is the emerging concept that CK2 can be effectively targeted for cancer therapy. 相似文献
992.
Martina Inga Kirsch Birgit Hülseweh Christoph Nacke Torsten Rülker Thomas Schirrmann Hans-Jürgen Marschall Michael Hust Stefan Dübel 《BMC biotechnology》2008,8(1):66
Background
Venezuelan equine encephalitis virus (VEEV) belongs to the Alphavirus group. Several species of this family are also pathogenic to humans and are recognized as potential agents of biological warfare and terrorism. The objective of this work was the generation of recombinant antibodies for the detection of VEEV after a potential bioterrorism assault or an natural outbreak of VEEV. 相似文献993.
Real-time Investigation of SV40 Large T-antigen Helicase Activity Using Surface Plasmon Resonance 总被引:1,自引:0,他引:1
Jason Plyler Karl Jasheway Bodin Tuesuwan Jessica Karr Jarryd S. Brennan Sean M. Kerwin Wendi M. David 《Cell biochemistry and biophysics》2009,53(1):43-52
The simian virus 40 (SV40) genome is a model system frequently employed for investigating eukaryotic replication. Large T-antigen
(T-ag) is a viral protein responsible for unwinding the SV40 genome and recruiting necessary host factors prior to replication.
In addition to duplex unwinding T-ag possesses G-quadruplex DNA helicase activity, the physiological consequence of which
is unclear. However, formation of G-quadruplex DNA structures may be involved in genome maintenance and function, and helicase
activity to resolve these structures may be necessary for efficient replication. We report the first real-time investigation
of SV40 T-ag helicase activity using surface plasmon resonance (SPR). In the presence of ATP, T-ag was observed to bind to
immobilized single-stranded DNA, forked duplex DNA, and the human telomeric foldover quadruplex DNA sequence. Inhibition of
T-ag duplex helicase activity was observable in real-time and the intramolecular quadruplex was unwound.
相似文献
Wendi M. DavidEmail: |
994.
995.
The size hierachies of a perennial grass population, Elymus nutans, which distributes throghout the subalpine meadow has been studied. A two-year experiment was designed to include seven treatments of different densities and measurements of inequality and distributions of individual mass of the population at different harvest time from 1987 to 1989. Individual mass under each of the seven treatments did not reveal a normal or lognormal distribution. No skewness values smaller than 0.5 occurred in our 48 sets of data, which implied that the distribution of the indiciduals of E. nutans population at any density skewed to small individuals. This result emphasized an evidence that there were differences between perennial grasses and annual grasses in responding to intraspecies competition. Size inequality did not increase with increasing population densities. This however, was not in concert with the results of experiments from others. Size inequality, on the other hand, was wore prominent in the period of vegetative growth than in the period of maturity. 相似文献
996.
Gunnar W. Schade Sheena J. Solomon Ebba Dellwik Kim Pilegaard Annette Ladstätter-Weissenmayer 《Biogeochemistry》2011,106(3):337-355
In-canopy mixing ratio gradients and above-canopy fluxes of several volatile organic compounds (VOCs) were measured using
a commercial proton transfer reaction mass spectrometer (PTR-MS) in a European beech (Fagus sylvatica) forest in Denmark. Fluxes of methanol were bidirectional: Emission occurred during both day and night with highest fluxes
(0.2 mg C m−2 h−1) during a warm period; deposition occurred dominantly at daytime. Confirming previous branch-level measurements on beech,
the forest’s monoterpene emissions (0–0.5 mg C m−2 h−1), and in-canopy mixing ratios showed a diurnal cycle consistent with light-dependent emissions; a result contrasting temperature-only
driven emissions of most conifer species. Also emitted was acetone, but only at ambient temperatures exceeding 20°C. Slow
deposition dominated at lower temperatures. Our in-canopy gradient measurements contrast with earlier results from tropical
and pine forest ecosystems in that they did not show this beech ecosystem to be a strong sink for oxygenated VOCs (OVOCs).
Instead, their gradients were flat and only small deposition velocities (<0.2 cm s−1) were observed to the onsite soil. However, as methanol soil uptake was consistent and possibly related to soil moisture,
more measurements are needed to evaluate its soil sink strength. In turn, as canopy scale fluxes are net fluxes with stomatal
emissions from photosynthesizing leaves potentially affecting non-stomatal oxygenated VOC uptake, only independent, controlled
laboratory experiments may be successful in separating gross fluxes. 相似文献
997.
Qixiao Zhai Gang Wang Jianxin Zhao Xiaoming Liu Arjan Narbad Yong Q. Chen Hao Zhang Fengwei Tian Wei Chen 《Applied and environmental microbiology》2014,80(13):4063-4071
Our previous study confirmed the ability of Lactobacillus plantarum CCFM8610 to protect against acute cadmium (Cd) toxicity in mice. This study was designed to evaluate the protective effects of CCFM8610 against chronic Cd toxicity in mice and to gain insights into the protection mode of this strain. Experimental mice were divided into two groups and exposed to Cd for 8 weeks via drinking water or intraperitoneal injection. Both groups were further divided into four subgroups, control, Cd only, CCFM8610 only, and Cd plus CCFM8610. Levels of Cd were measured in the feces, liver, and kidneys, and alterations of several biomarkers of Cd toxicity were noted. The results showed that when Cd was introduced orally, cotreatment with Cd and CCFM8610 effectively decreased intestinal Cd absorption, reduced Cd accumulation in tissue, alleviated tissue oxidative stress, reversed hepatic and renal damage, and ameliorated the corresponding histopathological changes. When Cd was introduced intraperitoneally, administration of CCFM8610 did not have an impact on tissue Cd accumulation or reverse the activities of antioxidant enzymes. However, CCFM8610 still offered protection against oxidative stress and reversed the alterations of Cd toxicity biomarkers and tissue histopathology. These results suggest that CCFM8610 is effective against chronic cadmium toxicity in mice. Besides intestinal Cd sequestration, CCFM8610 treatment offers direct protection against Cd-induced oxidative stress. We also provide evidence that the latter is unlikely to be mediated via protection against Cd-induced alteration of antioxidant enzyme activities. 相似文献
998.
Gene flow from transgenic plants to compatible wild relatives is one of the major impediments to the development of the culture
of genetically engineered crop plants. In this work, the flow of EPSPS (conferring resistance to glyphosate) gene of transgene Brassica napus toward the untransgene B. napus and wild relative species Orychophragmus violaceus in an open field (1 ha) was studied. The data related to only the 2004 and 2005 autumn season on one location of southwest
of China. Pollen dispersal and fertilization of the target plants were favored and a detailed analysis of the hybrid offspring
was performed. In field, the data studied show that the gene flow frequency was 0.16% between GM and non-GM B. napus at a distance of 1 m from the transgenic donor area. The crosspollination frequency was 0.05% between GM and non-GM B. napus at a distance of 5 m from the transgenic donor area. At a distance of 10 m, no crosspollination was observed. According to
the results of this study, B. napus transgene flow was low. However, the wild relative species O. violaceus could not be fertilized by the transgenic pollen of B. napus, no matter what the distance was. 相似文献
999.
Julio A. Camarero Youngeun Kwon 《International journal of peptide research and therapeutics》2008,14(4):351-357
Many experimental approaches in biology and biophysics, as well as applications in diagnosis and drug discovery, require proteins
to be immobilized on solid supports. Protein microarrays, for example, provide a high-throughput format to study biomolecular
interactions. The technique employed for protein immobilization is a key to the success of these applications. Recent biochemical
developments are allowing, for the first time, the selective and traceless immobilization of proteins generated by cell-free
systems without the need for purification and/or reconcentration prior to the immobilization step. 相似文献
1000.
Jing Wang Yuka Yashiro Yuriko Sakaguchi Tsutomu Suzuki Kozo Tomita 《Nucleic acids research》2022,50(8):4713
Contact-dependent growth inhibition is a mechanism of interbacterial competition mediated by delivery of the C-terminal toxin domain of CdiA protein (CdiA–CT) into neighboring bacteria. The CdiA–CT of enterohemorrhagic Escherichia coli EC869 (CdiA–CTEC869) cleaves the 3′-acceptor regions of specific tRNAs in a reaction that requires the translation factors Tu/Ts and GTP. Here, we show that CdiA–CTEC869 has an intrinsic ability to recognize a specific sequence in substrate tRNAs, and Tu:Ts complex promotes tRNA cleavage by CdiA–CTEC869. Uncharged and aminoacylated tRNAs (aa-tRNAs) were cleaved by CdiA–CTEC869 to the same extent in the presence of Tu/Ts, and the CdiA–CTEC869:Tu:Ts:tRNA(aa-tRNA) complex formed in the presence of GTP. CdiA–CTEC869 interacts with domain II of Tu, thereby preventing the 3′-moiety of tRNA to bind to Tu as in canonical Tu:GTP:aa-tRNA complexes. Superimposition of the Tu:GTP:aa-tRNA structure onto the CdiA–CTEC869:Tu structure suggests that the 3′-portion of tRNA relocates into the CdiA–CTEC869 active site, located on the opposite side to the CdiA–CTEC869 :Tu interface, for tRNA cleavage. Thus, CdiA–CTEC869 is recruited to Tu:GTP:Ts, and CdiA–CT:Tu:GTP:Ts recognizes substrate tRNAs and cleaves them. Tu:GTP:Ts serves as a reaction scaffold that increases the affinity of CdiA–CTEC869 for substrate tRNAs and induces a structural change of tRNAs for efficient cleavage by CdiA–CTEC869. 相似文献