共查询到20条相似文献,搜索用时 31 毫秒
1.
Arivazhagan Rajendran Chunxia Zhao Burki Rajendar Viruthachalam Thiagarajan Yusuke Sato Seiichi Nishizawa Norio Teramae 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
We explain here the various non-covalent interactions which are responsible for the different binding modes of a small ligand with DNA.Methods
The combination of experimental and theoretical methods was used.Results
The interaction of amiloride with thymine was found to depend on the bases flanking the AP site and different binding modes were observed for different flanking bases. Molecular modeling, absorption studies and binding constant measurements support for the different binding patterns. The flanking base dependent recognition of AP site phosphates was investigated by 31P NMR experiments. The thermodynamics of the ligand–nucleotide interaction was demonstrated by isothermal titration calorimetry. The emission behavior of amiloride was found to depend on the bases flanking the AP site. Amiloride photophysics in the context of AP-site containing DNA is investigated by time-dependent density functional theory.Conclusions
Flanking bases affect the ground and excited electronic states of amiloride when binding to AP site, which causes flanking base-dependent fluorescence signaling.General significance
The various noncovalent interactions have been well characterized for the determination of nucleic acid structure and dynamics, and protein–DNA interactions. However, these are not clear for the DNA–small molecule interactions and we believe that our studies will bring a new insight into such phenomena. 相似文献2.
Mrityunjay Tyagi Rahul Bhattacharyya Ajay Kumar BauriBirija Sankar Patro Subrata Chattopadhyay 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Given that lung cancer is the second leading cause of cancer-related deaths with low survival rates, the project was aimed to formulate an efficient drug with minimum side effects, and rationalize its action mechanistically.Methods
Mitochondria deficient cells, shRNA-mediated BCL2 and ATM depleted cells and pharmacological inhibition of DNA-damage response proteins were employed to explore the signaling mechanism governed between nucleus and mitochondria in response to mal C.Results
Mal C decreased cell viability in three lung carcinoma cells, associated with DNA damage, p38-MAPK activation, imbalance in BAX/BCL2 expression, mitochondrial dysfunction and cytochrome-c release. Mitochondria depletion and p38-MAPK inhibition made A549 cells extremely resistant, but BCL2 knock-down partially sensitized the cells to mal C treatment. The mal C-induced apoptosis in A549 cells was initiated by DNA single strand breaks that led to double strand breaks (DSBs). DSB generation paralleled the induction of ATM- and ATR-mediated CHK1 phosphorylation. ATM silencing and ATR inhibition partially attenuated the mal C-induced p38-MAPK activation, CHK1 phosphorylation and apoptosis, which were completely suppressed by CHK1 inhibition.Conclusions
Mal C activates the ATM-CHK1-p38 MAPK cascade to cause mitochondrial cell death in lung carcinoma cells.General significance
Given that mal C has appreciable natural abundance and is non-toxic to mice, further in vivo evaluation would help in establishing its anti-cancer property. 相似文献3.
Matteo Nadai Giovanna Sattin Giorgio Palù Manlio Palumbo Sara N. Richter 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
G-quadruplexes are polymorphic non-canonical nucleic acid conformations involved both in physiological and pathological processes. Given the high degree of folding heterogeneity and comparable conformational stabilities, different G-quadruplex forms can occur simultaneously, hence rendering the use of basic instrumental methods for structure determination, like X-ray diffraction or NMR, hardly useful. Footprinting techniques represent valuable and relatively rapid alternative to characterize DNA folding. The natural diterpenoid clerocidin is an alkylating agent that specifically reacts at single-stranded DNA regions, with different mechanisms depending on the exposed nucleotide.Methods
Clerocidin was used to footprint G-quadruplex structures formed by telomeric and oncogene promoter sequences (c-myc, bcl-2, c-kit2), and by the thrombin binding aptamer.Results
The easy modulability of CL reactivity towards DNA bases permitted to discriminate fully and partially protected sites, highlights stretched portions of the G-quadruplex conformation, and discriminate among topologies adopted by one sequence in different environmental conditions. Importantly, CL displayed the unique property to allow detection of G-quadruplex folding within a duplex context.Conclusions
CL is a finely performing new tool to unveil G-quadruplex arrangements in DNA sequences under genomically relevant conditions.General significance
Nucleic acid G-quadruplex structures are an emerging research field because of the recent indication of their involvement in a series of key biological functions, in particular in regulation of proliferation-associated gene expression. The use of clerocidin as footprinting agent to identify G-quadruplex structures under genomically relevant conditions may allow detection of new G-quadruplex-based regulatory regions. 相似文献4.
Alexandra A. Kuznetsova Nikita A. Kuznetsov Alexander A. Ishchenko Murat K. Saparbaev Olga S. Fedorova 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
DNA glycosylases remove the modified, damaged or mismatched bases from the DNA by hydrolyzing the N-glycosidic bonds. Some enzymes can further catalyze the incision of a resulting abasic (apurinic/apyrimidinic, AP) site through β- or β,δ-elimination mechanisms. In most cases, the incision reaction of the AP-site is catalyzed by special enzymes called AP-endonucleases.Methods
Here, we report the kinetic analysis of the mechanisms of modified DNA transfer from some DNA glycosylases to the AP endonuclease, APE1. The modified DNA contained the tetrahydrofurane residue (F), the analogue of the AP-site. DNA glycosylases AAG, OGG1, NEIL1, MBD4cat and UNG from different structural superfamilies were used.Results
We found that all DNA glycosylases may utilise direct protein–protein interactions in the transient ternary complex for the transfer of the AP-containing DNA strand to APE1.Conclusions
We hypothesize a fast “flip-flop” exchange mechanism of damaged and undamaged DNA strands within this complex for monofunctional DNA glycosylases like MBD4cat, AAG and UNG. Bifunctional DNA glycosylase NEIL1 creates tightly specific complex with DNA containing F-site thereby efficiently competing with APE1. Whereas APE1 fast displaces other bifunctional DNA glycosylase OGG1 on F-site thereby induces its shifts to undamaged DNA regions.General significance
Kinetic analysis of the transfer of DNA between human DNA glycosylases and APE1 allows us to elucidate the critical step in the base excision repair pathway. 相似文献5.
Gunjan Tyagi Shrikant Pradhan Tapasya Srivastava Ranjana Mehrotra 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Allicin has received much attention due to its anti-proliferative activity and not-well elucidated underlying mechanism of action. This work focuses towards determining the cellular toxicity of allicin and understanding its interaction with nucleic acid at molecular level.Methods
MTT assay was used to assess the cell viability of A549 lung cancer cells against allicin. Fourier transform infrared (FTIR) and UV-visible spectroscopy were used to study the binding parameters of nucleic acid-allicin interaction.Results
Allicin inhibits the proliferation of cancer cells in a concentration dependent manner. FTIR spectroscopy exhibited that allicin binds preferentially to minor groove of DNA via thymine base. Analysis of tRNA allicin complex has also revealed that allicin binds primarily through nitrogenous bases. Some amount of external binding with phosphate backbone was also observed for both DNA and RNA. UV visible spectra of both DNA allicin and RNA allicin complexes showed hypochromic shift with an estimated binding constant of 1.2 × 104 M- 1 for DNA and 1.06 × 103 M− 1for RNA binding. No major transition from the B-form of DNA and A-form of RNA is observed after their interaction with allicin.Conclusions
The results demonstrated that allicin treatment inhibited the proliferation of A549 cells in a dose-dependent manner. Biophysical outcomes are suggestive of base binding and helix contraction of nucleic acid structure upon binding with allicin.General significance
The results describe cytotoxic potential of allicin and its binding properties with cellular nucleic acid, which could be helpful in deciphering the complete mechanism of cell death exerted by allicin. 相似文献6.
Jarmila Mlcouskova Jaroslav Malina Vojtech Novohradsky Jana Kasparkova Seiji Komeda Viktor Brabec 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012
Background
The design of anticancer metallodrugs is currently focused on platinum complexes which form on DNA major adducts that cannot readily be removed by DNA repair systems. Hence, antitumor azolato-bridged dinuclear PtII complexes, such as [{cis-Pt(NH3)2}2(μ‐OH)(μ-pyrazolate)]2+ (AMPZ), have been designed and synthesized. These complexes exhibit markedly higher toxic effects in tumor cell lines than mononuclear conventional cisplatin.Methods
Biophysical and biochemical aspects of the alterations induced in short DNA duplexes uniquely and site-specifically modified by the major DNA adduct of AMPZ, namely 1,2-GG intrastrand cross-links, were examined. Attention was also paid to conformational distortions induced in DNA by the adducts of AMPZ and cisplatin, associated alterations in the thermodynamic stability of the duplexes, and recognition of these adducts by high-mobility-group (HMG) domain proteins.Results
Chemical probing of DNA conformation, DNA bending studies and translesion synthesis by DNA polymerase across the platinum adduct revealed that the distortion induced in DNA by the major adduct of AMPZ was significantly less pronounced than that induced by similar cross-links from cisplatin. Concomitantly, the cross-link from AMPZ reduced the thermodynamic stability of the modified duplex considerably less. In addition, HMGB1 protein recognizes major DNA adducts of AMPZ markedly less than those of cisplatin.General significance
The experimental evidence demonstrates why the major DNA adducts of the new anticancer azolato-bridged dinuclear PtII complexes are poor substrates for DNA repair observed in a previously published report. The relative resistance to DNA repair explains why these platinum complexes show major pharmacological advantages over cisplatin in tumor cells. 相似文献7.
Fusao Hirata Lisa M. ThibodeauAiko Hirata 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
While annexin A1 in nuclei is proposed to be involved in cell transformation, its functions remain poorly understood. Since annexin A1 has the consensus motif, 160LKRD, for SUMOylation as well as Ks, acceptors for ubiquitination that regulates localization and functions of proteins, we investigated SUMOylation and ubiquitination of annexin A1.Methods
SUMOylation and ubiquitination of bovine annexin A1 were biochemically tested in vitro by purified proteins, and were confirmed by cell experiments with L5178 lymphoma cells. Effects of the modifications on DNA helicase activity were measured by ssDNA binding activity and by dsDNA unwinding activity.Results
SUMOylation of annexin A1 was catalyzed by Ubc9, while its ubiquitination was by Rad6-Rad 18. Ubiquitinated annexin A1 had higher affinity for damaged DNA, and promoted in vitro translesion DNA synthesis by Pol β. In mouse lymphoma L5178Y tk(+/−) cells, levels of SUMOylated annexin A1 decreased by DNA damaging agents, MMS or As3+, whereas those of ubiquitinated annexin A1 increased under the same conditions.Conclusion
These observations suggest but do not necessarily prove that ubiquitinated annexin A1 in nuclei may be involved in DNA damage response, while SUMOylated annexin A1 functions in proliferation–differentiation.Significance
Ubiquitination of annexin A1 may play an important role in mutagenesis, an initial step of cell transformation. 相似文献8.
Jolanta Brzezinska Zofia GdaniecWojciech T. Markiewicz 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
The nature of the polyamine–DNA interactions at a molecular level is not clearly understood.Methods
In order to shed light on the binding preferences of polyamine with nucleic acids, the NMR solution structure of the DNA duplex containing covalently bound spermine was determined.Results
The structure of 4-N-[4,9,13-triazatridecan-1-yl]-2′-deoxycytidine (dCSp) modified duplex was compared to the structure of the reference duplex. Both duplexes are regular right-handed helices with all attributes of the B-DNA form. The spermine chain which is located in a major groove and points toward the 3′ end of the modified strand does not perturb the DNA structure.Conclusion
In our study the charged polyamine alkyl chain was found to interact with the DNA surface. In the majority of converged structures we identified the presumed hydrogen bonding interactions between O6 and N7 atoms of G4 and the first internal –NH2+− amino group. Additional interaction was found between the second internal –NH2+− amino group and the oxygen atom of the phosphate of C3 residue.General significance
The knowledge of the location and nature of a structure-specific binding site for spermine in DNA should be valuable in understanding gene expression and in the design of new therapeutic drugs. 相似文献9.
Ole Ammerpohl José I. Martín-SuberoJulia Richter Inga VaterReiner Siebert 《Biochimica et Biophysica Acta (BBA)/General Subjects》2009
Background
In the recent past large progress has been made in the analysis of the epigenome, the entirety of epigenetic modifications, and its meaning for the implementation of the genetic code. Besides histone modifications and miRNA expression, DNA methylation is one of the key players in the field of epigenetics, involved in numerous regulatory processes.Methods
In the present review we focus on methods for the analysis of DNA methylation patterns and present an overview about techniques and basic principles available for this purpose.Results and general significance
We here discuss advantages and disadvantages of various methods and their feasibility for specific tasks of DNA methylation analysis. 相似文献10.
Background
Single cell gel electrophoresis, or the comet assay, was devised as a sensitive method for detecting DNA strand breaks, at the level of individual cells. A simple modification, incorporating a digestion of DNA with a lesion-specific endonuclease, makes it possible to measure oxidised bases.Scope of review
With the inclusion of formamidopyrimidine DNA glycosylase to recognise oxidised purines, or Nth (endonuclease III) to detect oxidised pyrimidines, the comet assay has been used extensively in human biomonitoring to monitor oxidative stress, usually in peripheral blood mononuclear cells.Major conclusions
There is evidence to suggest that the enzymic approach is more accurate than chromatographic methods, when applied to low background levels of base oxidation. However, there are potential problems of over-estimation (because the enzymes are not completely specific) or under-estimation (failure to detect lesions that are close together). Attempts have been made to improve the inter-laboratory reproducibility of the comet assay.General significance
In addition to measuring DNA damage, the assay can be used to monitor the cellular or in vitro repair of strand breaks or oxidised bases. It also has applications in assessing the antioxidant status of cells. In its various forms, the comet assay is now an invaluable tool in human biomonitoring and genotoxicity testing. This article is part of a Special Issue entitled Current methods to study reactive oxygen species - pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn. 相似文献11.
Wenjia Liu Anna Konermann Tao Guo Andreas Jäger Liqiang Zhang Yan Jin 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Cellular plasticity and complex functional requirements of the periodontal ligament (PDL) assume a local stem cell (SC) niche to maintain tissue homeostasis and repair. Here, pathological alterations caused by inflammatory insults might impact the regenerative capacities of these cells. As bone homeostasis is fundamentally controlled by Wnt-mediated signals, it was the aim of this study to characterize the SC-like capacities of cells derived from PDL and to investigate their involvement in bone pathophysiology especially regarding the canonical Wnt pathway.Methods
PDLSCs were investigated for their SC characteristics via analysis of cell surface marker expression, colony forming unit efficiency, proliferation, osteogenic differentiation and adipogenic differentiation, and compared to bone marrow derived mesenchymal SCs (BMMSCs). To determine the impact of both inflammation and the canonical Wnt pathway on osteogenic differentiation, cells were challenged with TNF-α, maintained with or without Wnt3a or DKK-1 under osteogenic induction conditions and investigated for p-IκBα, p-NF-κB, p-Akt, β-catenin, p-GSK-3β, ALP and Runx2.Results
PDLSCs exhibit weaker adipogenic and osteogenic differentiation capacities compared to BMMSCs. TNF-α inhibited osteogenic differentiation of PDLSCs more than BMMSCs mainly through regulating canonical Wnt pathway. Blocking the canonical Wnt pathway by DKK-1 reconstituted osteogenic differentiation of PDLSCs under inflammatory conditions, whereas activation by Wnt3a increased osteogenic differentiation of BMMSCs.Conclusions
Our results suggest a diverse regulation of the inhibitory effect of TNF-α in BMMSCs and PDLSCs via canonical Wnt pathway modulation.General significance
These findings provide novel insights on PDLSC SC-like capacities and their involvement in bone pathophysiology under the impact of the canonical Wnt pathway. 相似文献12.
13.
Da-En Cheng Jen-Yu Hung Ming-Shyan Huang Ya-Ling Hsu Chi-Yu Lu Eing-Mei Tsai Ming-Feng Hou Po-Lin Kuo 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Tolerogenic dendritic cells (tDCs) play important roles in immune tolerance, autoimmune disease, tissue transplantation, and the tumor micro-environment. Factors that induce tDCs have been reported, however the intracellular mechanisms involved are rarely discussed.Methods
Circulating CD14+CD16+ of breast cancer patients and induced CD14+CD16+ DCs were identified as tDCs by treating CD14+ monocytes with galectin-1 and cancer cell-derived medium combined with IL-4 and GM-CSF. In addition, the 4T1 breast cancer syngeneic xenograft model was used to investigate the effect of galectin-1 in vivo.Results
The CD14+CD16+ tDC population in the breast cancer patients was comparatively higher than that in the healthy donors, and both the MDA-MB-231 conditioned medium and galectin-1 could induce tDC differentiation. In a BALB/c animal model, the 4T1 breast cancer cell line enhanced IL-10 expression in CD11c+ DCs which was down-regulated after knocking down the galectin-1 expression of 4T1 cells. Analysis of galectin-1 interacting proteins showed that myosin IIa was a major target of galectin-1 after internalization through a caveolin-dependent endocytosis. Myosin IIa specific inhibitor could diminish the effects of galectin-1 on monocyte-derived tDCs and also block the 4T1 cell induced CD11c+/Ly6G+/IL-10+ in the BALB/c mice.Conclusions
Galectin-1 can induce tDCs after internalizing into CD14+ monocytes through the caveolae-dependent pathway and activating myosin IIa. For the breast cancer patients with a high galectin-1 expression, blebbistatin and genistein show potential in immune modulation and cancer immunotherapy.General significance
Myosin IIa activation and galectin-1 endocytosis are important in tumor associated tDC development. 相似文献14.
Hiroshi Tsujikawa Takehiro Shoda Toshiyuki Mizota Kazuhiko Fukuda 《Biochimica et Biophysica Acta (BBA)/General Subjects》2009
Background
Morphine has been shown to affect the function of immune system, but the precise mechanism remains to be elucidated. The present study was aimed to clarify the mechanism for the morphine-induced immune suppression by analyzing the direct effect of morphine on human CD3+ T cells.Methods
To identify genes up-regulated by action of morphine on the opioid receptor expressed in CD3+ T cells, PCR-select cDNA subtraction was performed by the use of total RNA from human CD3+ T cells treated with morphine in the presence and absence of naloxone.Results
We show that p53 and damage-specific DNA binding protein 2 (ddb2) genes are up-regulated by morphine in a naloxone-sensitive manner. Furthermore, the results indicate that DNA damage, quantified by apurinic–apyrimidinic site counting assay and phosphorylation of Ser-15 in P53 protein, is induced in CD3+ T cells by morphine in a naloxone-sensitive manner.General significance
Because it was shown that only the κ opioid receptor gene is expressed in CD3+ T cells in the opioid receptor family, the present study suggests that morphine induces DNA damage through the action on the κ opioid receptor, which leads to immune suppression by activation of P53-mediated signal transduction. 相似文献15.
Ana Paula Zanatta Leila Zanatta Renata Gonçalves Ariane Zamoner Fátima Regina Mena Barreto Silva 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
The secretory activity of Sertoli cells (SC) is dependent on ion channel functions and protein synthesis and is critical to ongoing spermatogenesis. The aim of this study was to investigate the mechanism of action associated with a non-metabolizable amino acid [14C]-MeAIB (α-(methyl-amino)isobutyric acid) accumulation stimulated by T4 and the role of the integrin receptor in this event, and also to clarify whether the T4 effect on MeAIB accumulation and on Ca2+ influx culminates in cell secretion.Methods
We have studied the rapid and plasma membrane initiated effects of T4 by using 45Ca2+ uptake and [45C]-MeAIB accumulation assays, respectively. Thymidine incorporation into DNA was used to monitor nuclear activity and quinacrine to analyze the secretory activity on SC.Results
The stimulation of MeAIB accumulation by T4 appears to be mediated by the integrin receptor in the plasma membrane since tetrac and RGD peptide were able to nullify the effect of this hormone. In addition, T4 increases extracellular Ca2+ uptake and Ca2+ from intracellular stocks to enhance nuclear activity, but this genomic action seems not to influence SC secretion mediated by T4. Also, the cytoskeleton and ClC-3 chloride channel contribute to the membrane-associated responses of SC.Conclusions
T4 integrin receptor activation ultimately determines the plasma membrane responses on amino acid transport in SC, but it is not involved in calcium influx, cell secretion or the nuclear effect of the hormone.General significance
The integrin receptor activation by T4 may take a role in plasma membrane processes involved in the male reproductive system. 相似文献16.
Jerzy Ciesiołka Małgorzata Jeżowska-Bojczuk Jan Wrzesiński Kamila Stokowa-Sołtys Justyna Nagaj Aleksandra Kasprowicz Leszek Błaszczyk Wojciech Szczepanik 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Bacitracin is a polypeptide antibiotic active against Gram-positive bacterial strains. Its mechanism of action postulates disturbing the cell wall synthesis by inhibiting dephosphorylation of the lipid carrier. We have discovered that bacitracin induces degradation of nucleic acids, being particularly active against RNA.Methods
In the examination of the nucleolytic activity of bacitracin several model RNA and DNA oligomers were used. The oligomers were labeled at their 5′ ends with 32P radioisotope and following treatment with bacitracin the cleavage sites and efficiency were determined.Results and conclusions
Bacitracin induces degradation of RNA at guanosine residues, preferentially in single-stranded RNA regions. Bacitracin is also able to degrade DNA to some extent but comparable effects to those observed with RNA require its 10-fold higher concentration. The sites of degradation in DNA are very infrequent and preferentially occur near cytidine residues. Free radicals are not involved in the reaction, and which probably proceeds via a hydrolytic mechanism. The phosphate groups at the cleavage sites are present at the 3' ends of RNA products and at the 5' ends of DNA fragments. Importantly, the presence of EDTA does not influence RNA degradation but completely inhibits the degradation of DNA. For DNA degradation divalent metal ions like Mg2 +, Mn2 + or Zn2 + are absolutely necessary.General significance
The ability of bacitracin to degrade nucleic acids via a hydrolytic mechanism was a surprising observation, and it is of interest whether these properties can contribute to its mechanisms of action during antibiotic treatment. 相似文献17.
Antonella Santoro Anna Rita CappelloMarianna Madeo Emanuela MartelloDomenico Iacopetta Vincenza Dolce 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011
Background
Fosfomycin is widely used to treat urinary tract and pediatric gastrointestinal infections of bacteria. It is supposed that this antibiotic enters cells via two transport systems, including the bacterial Glycerol-3-phosphate Transporter (GlpT). Impaired function of GlpT is one mechanism for fosfomycin resistance.Methods
The interaction of fosfomycin with the recombinant and purified GlpT of Escherichia coli reconstituted in liposomes has been studied. IC50 and the half-saturation constant of the transporter for external fosfomycin (Ki) were determined by transport assay of [14C]glycerol-3-phosphate catalyzed by recombinant GlpT. Efficacy of fosfomycin on growth rates of GlpT defective bacteria strains transformed with recombinant GlpT was measured.Results
Fosfomycin, externally added to the proteoliposomes, poorly inhibited the glycerol-3-phosphate/glycerol-3-phosphate antiport catalyzed by the reconstituted transporter with an IC50 of 6.4 mM. A kinetic analysis revealed that the inhibition was completely competitive, that is, fosfomycin interacted with the substrate-binding site and the Ki measured was 1.65 mM. Transport assays performed with proteoliposomes containing internal fosfomycin indicate that it was not very well transported by GlpT. Complementation study, performed with GlpT defective bacteria strains, indicated that the fosfomycin resistance, beside deficiency in antibiotic transporter, could be due to other gene defects.Conclusions
The poor transport observed in a reconstituted system together with the high value of Ki and the results of complementation study well explain the usual high dosage of this drug for the treatment of the urinary tract infections.General significance
This is the first report regarding functional analysis of interaction between fosfomycin and GlpT. 相似文献18.
Satoshi Hara Tatsuya Nojima Kohji Seio Masasuke Yoshida Toru Hisabori 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Thiol-mediated redox regulation of proteins plays a key role in many cellular processes.Methods
To understand the redox status of cysteinyl thiol groups of the desired proteins, we developed a new maleimide reagent: a maleimide-conjugated single strand DNA, DNA-maleimide (DNA-Mal).Results
DNA-Mal labelled proteins run as a distinct band on SDS-PAGE, with a discrete 9.32 kDa mobility shift per label regardless of the protein species or electrophoretic conditions.Conclusions
DNA-Mal labels free thiols like standard maleimide reagents, but possesses practical advantages in titration of the number and relative content of free thiols in a protein.General significance
The versatility of DNA molecule enhances the application of DNA-Mal in a broader range of cysteine containing proteins. 相似文献19.
Narayana Nagesh G. Raju R. Srinivas P. Ramesh M. Damoder Reddy Ch. Raji Reddy 《Biochimica et Biophysica Acta (BBA)/General Subjects》2015
Background
Telomeric and NHE III1, a c-MYC promoter region is abundant in guanine content and readily form G-quadruplex structures. Small molecules that stabilize G-quadruplex DNA were shown to reduce oncoprotein expression, initiate apoptosis and they may function as anticancer molecules.Methods
Electrospray ionization mass spectrometry, spectroscopy, isothermal titration calorimetry, Taq DNA polymerase stop assay, real time PCR and luciferase reporter assay. Cell migration assay to find out the effect of derivatives on normal as well as cancer cell proliferation.Results
Among three different dihydroindolizino indole derivatives, 4-cyanophenyl group attached derivative has shown maximum affinity, selective interaction and higher stability towards G-quadruplex DNA over dsDNA. Further, as a potential G-quadruplex DNA stabilizer, 4-cyanophenyl linked dihydroindolizino indole derivative was found to be more efficient in inhibiting in vitro DNA synthesis, c-MYC expression and cancer cell proliferation among human cancer cells.Conclusion
The present study reveals that dihydroindolizino indole derivative having 4-cyanophenyl group has potential to stabilize G-quadruplex DNA and exhibit anticancer activity.General significance
These studies are useful in the identification and synthesis of lead derivatives that will selectively stabilize G-quadruplex DNA and function as anticancer agents. 相似文献20.
Sanae Benabou Rubén Ferreira Anna Aviñó Carlos González Sébastien Lyonnais Maria Solà Ramon Eritja Joaquim Jaumot Raimundo Gargallo 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014