Author: Jessica.F

He, Yanping; Zhou, Yibo; Chen, Da; Liu, Juewen published the artcile< Global Folding of a Na+-Specific DNAzyme Studied by FRET>, Name: 7H-Purin-2-amine, the main research area is DNAzymes; FRET; aptamers; protein folding; sodium.

Recently, a few RNA-cleaving DNAzymes have been isolated with excellent specificity for Na+, and some of them contain a Na+-binding aptamer. This metal recognition mechanism is different from that of most previously reported DNAzymes. When using 2-aminopurine (2AP) as a probe, interesting local folding induced by Na+ was recently observed In this work, FRET was used to probe the global folding of the Ce13d DNAzyme; one of the Na+-specific DNAzymes. FRET pairs were at different locations, which yielded a total of five constructs to probe the three-way junction structure with a large loop. With endlabeled DNAzymes, the global structure appears to be quite rigid with little folding upon adding up to 200 mM monovalent metal ions, although some minor differences were observed between Li+, Na+, and K+. This lack of significant conformational change is also consistent with CD spectroscopy data. The loop was then labeled with an internal tetramethylrhodamine fluorophore at the G14 position, and its cleavage activity was partially retained. A clear Na+-dependent folding was observed with spectral crossover. From a biosensing standpoint, global folding based sensors are unlikely to work due to the overall rigid structure of the DNAzyme. Therefore, the best way to use this DNAzyme to discriminate Na+ from K+ is based on cleavage activity, followed by probing local folding, whereas global folding is the least effective for metal discrimination.

ChemBioChem published new progress about 452-06-2. 452-06-2 belongs to class imidazoles-derivatives, and the molecular formula is C5H5N5, Name: 7H-Purin-2-amine.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Tong, Ying; Ye, Chao; Ren, Xing-Sheng; Qiu, Yun; Zang, Ying-Hao; Xiong, Xiao-Qing; Wang, Jue-Jin; Chen, Qi; Li, Yue-Hua; Kang, Yu-Ming; Zhu, Guo-Qing published the artcile< Exosome-Mediated Transfer of ACE (Angiotensin-Converting Enzyme) From Adventitial Fibroblasts of Spontaneously Hypertensive Rats Promotes Vascular Smooth Muscle Cell Migration>, Recommanded Product: p-Benzenediacrylanilide, 4′,4′′-di-2-imidazolin-2-yl-, dihydrochloride, the main research area is ACE fibroblast exosome vascular smooth muscle cell migration hypertension; captopril; exosomes; fibroblasts; hypertension; vascular remodeling.

Migration of vascular smooth muscle cells (VSMCs) is pivotal for vascular remodeling in hypertension. Vascular adventitial fibroblasts (AFs) are important in the homeostasis of vascular structure. This study is designed to investigate the roles of AF exosomes (AFE) in VSMC migration and underling mechanism. Primary VSMCs and AFs were obtained from the aorta of spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. VSMC migration was evaluated with Boyden chamber assay and wound healing assay. AFE from WKY rats and SHR were isolated and identified. AFE from SHR promoted but AFE from WKY rats had no significant effect on VSMC migration. The effects of AFE on VSMC migration were prevented by an exosome inhibitor GW4869, an AT1R (Ang II [angiotensin II] type 1 receptor) antagonist losartan, or an inhibitor of ACE (angiotensin-converting enzyme) captopril. ACE contents and activity were much higher in AFE from SHR than those from WKY rats. There were no significant difference in Ang II and AT1R mRNA and protein levels between AFE from SHR and AFE from WKY rats. AFE from SHR increased Ang II and ACE contents and ACE activity in VSMCs of WKY rats and SHR. The changes of Ang II contents and ACE activity were prevented by captopril. ACE knockdown in AFs reduced ACE contents and activity in AFE from SHR and inhibited AFE-induced migration of VSMCs of WKY rats and those of SHR. These results indicate that exosomes from AFs of SHR transfer ACE to VSMCs, which increases Ang II levels and activates AT1R in VSMCs and thereby promotes VSMC migration.

Hypertension published new progress about Angiotensin AT1 receptors Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 6823-69-4 belongs to class imidazoles-derivatives, and the molecular formula is C30H30Cl2N6O2, Recommanded Product: p-Benzenediacrylanilide, 4′,4′′-di-2-imidazolin-2-yl-, dihydrochloride.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Kunz, Peter C.; Klaeui, Wolfgang published the artcile< Zinc and cobalt(II) complexes of tripodal nitrogen ligands of the tris[2-substituted imidazol-4(5)-yl]-phosphane type. Biomimetic hydrolysis of an activated ester>, Category: imidazoles-derivatives, the main research area is tris imidazolyl phosphine ligand preparation zinc cobalt complexation; biomimetic ester hydrolysis zinc enzyme; nitrophenyl pyridine carboxylate hydrolysis kinetics zinc cobalt imidazolylphosphine catalyzed.

Novel tris[2-substituted imidazol-4(5)-yl]phosphane (4-TIPR) ligands 2b (R = Ph) and 2c (R = tBu) were prepared as model ligands for the tris(histidine) motif found in many zinc enzymes. They readily form cobalt and zinc nitrato and chloro complexes in protic solvents. The steric requirements of the substituents R in 4(5)-position of the 4-TIPR ligands (R = iPr (2a), Ph (2b), tBu (2c)) is discussed on the basis of their UV/VIS spectra. Zinc complexes of 2a and 2c were studied due to their ability to promote the hydrolysis of the activated ester 4-nitrophenyl pyridine-2-carboxylate (pNpic).

Collection of Czechoslovak Chemical Communications published new progress about Enzymes Role: BCP (Biochemical Process), BIOL (Biological Study), PROC (Process) (model). 36947-69-0 belongs to class imidazoles-derivatives, and the molecular formula is C7H12N2, Category: imidazoles-derivatives.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Kusama, Hitoshi; Konishi, Yoshinari; Sugihara, Hideki published the artcile< Data mining assisted by theoretical calculations for improving dye-sensitized solar cell performance>, Application of C4H5BrN2, the main research area is data mining theor calculation dye sensitized solar cell performance.

Data mining using exptl. data and information generated from theor. calculations is proposed to study dye-sensitized solar cells, which are complex systems. This method led to new knowledge about the influence of imidazole derivatives as additives in an electrolytic solution on the cell performance. It was found that the solar energy conversion efficiency is strongly correlated to the Mulliken charge of the carbon atom at position 4 in the imidazole group. This result indicates that data mining assisted by theor. calculations should facilitate the rate that cell performance is improved.

Solar Energy Materials & Solar Cells published new progress about Density functional theory (GGA, PBE-functional, DNP). 1003-21-0 belongs to class imidazoles-derivatives, and the molecular formula is C4H5BrN2, Application of C4H5BrN2.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Hu, Haifeng; Wang, Dong; Li, Lihong; Yin, Haiyang; He, Guoyu; Zhang, Yonghong published the artcile< Role of microRNA-335 carried by bone marrow mesenchymal stem cells-derived extracellular vesicles in bone fracture recovery>, Application In Synthesis of 6823-69-4, the main research area is microRNA335 mesenchymal stem cell extracellular vesicle bone fracture.

Mesenchymal stem cells (MSCs) have the potential to reduce healing time and treat nonunion in fracture patients. In this study, bone marrow MSCs-derived extracellular vesicles (B-EVs) were firstly extracted and identified. CD9-/- and normal mice were enrolled for the establishment of fracture models and then injected with B-EVs. Osteoblast differentiation and fracture recovery were estimated The levels of osteoblast-related genes were detected, and differentially expressed microRNAs (miRs) in B-EVs-treated normal fracture mice were screened and verified. The downstream mechanisms of miR were predicted and assessed. The loss-of functions of miR-335 in B-EV and gain-of-functions of VapB were performed in animal and cell experiments to evaluate their roles in bone fracture. Collectively, B-EVs promoted bone fracture recovery and osteoblast differentiation by releasing miR-335. miR-335 downregulation in B-EVs impaired B-EV functions in fracture recovery and osteoblast differentiation. miR-335 could target VapB, and VapB overexpression reversed the effects of B-EVs on osteoblast differentiation. B-EV treatment activated the Wnt/β-catenin pathway in fracture mice and osteoblasts-like cells. Taken together, the study suggested that B-EVs carry miR-335 to promote bone fracture recovery via VapB and the Wnt/β-catenin pathway. This study may offer insights into bone fracture treatment.

Cell Death & Disease published new progress about Angiogenesis. 6823-69-4 belongs to class imidazoles-derivatives, and the molecular formula is C30H30Cl2N6O2, Application In Synthesis of 6823-69-4.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Deng, Chun-Lei; Hu, Cheng-Biao; Ling, Sheng-Tao; Zhao, Na; Bao, Li-Hui; Zhou, Feng; Xiong, Ye-Cheng; Chen, Tao; Sui, Bing-Dong; Yu, Xiao-Rui; Hu, Cheng-Hu published the artcile< Photoreceptor protection by mesenchymal stem cell transplantation identifies exosomal MiR-21 as a therapeutic for retinal degeneration>, Application In Synthesis of 6823-69-4, the main research area is retinal degeneration mesenchymal stem cell transplantation MiR21 exosome.

Abstract: Photoreceptor apoptosis is recognized as one key pathogenesis of retinal degeneration, the counteraction of which represents a promising approach to safeguard visual function. Here, we discovered that intravitreal MSCT counteracted photoreceptor apoptosis and alleviated retinal morphol. and functional degeneration in a mouse model of photoreceptor loss induced by N-methyl-N-nitrosourea (MNU). Notably, therapeutic efficacy of MSCT and EXOT on MNU-induced retinal degeneration was long-lasting as photoreceptor preservance and retinal maintenance were detected even after 1-2 mo post to injection for only once. More importantly, using a natural occurring retinal degeneration model caused by a nonsense mutation of Phosphodiesterase 6b gene (Pde6bmut), we confirmed that MSCT and EXOT prevented photoreceptor loss and protected long-term retinal function. In deciphering therapeutic mechanisms regarding potential exosome-mediated communications, we identified that miR-21 critically maintained photoreceptor viability against MNU injury by targeting programmed cell death 4 (Pdcd4) and was transferred from MSC-derived exosomes in vivo for functional regulation. Further experiments revealed that miR-21 mediated therapeutic effects of EXOT on MNU-induced photoreceptor apoptosis and retinal dysfunction. These findings uncovered the efficacy and mechanism of MSCT-based photoreceptor protection, indicating exosomal miR-21 as a therapeutic for retinal degeneration.

Cell Death & Differentiation published new progress about Apoptosis. 6823-69-4 belongs to class imidazoles-derivatives, and the molecular formula is C30H30Cl2N6O2, Application In Synthesis of 6823-69-4.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Brovarets, Ol′ha O.; Hovorun, Dmytro M. published the artcile< Key microstructural mechanisms of the 2-aminopurine mutagenicity: Results of extensive quantum-chemical research>, HPLC of Formula: 452-06-2, the main research area is review quantum 2aminopurine mutagenicity tautomerization; 2-Aminopurine; H-bond: hydrogen bond; Watson–Crick↔wobble mutagenic tautomerization; induced mutation; quantum-chemical calculation; transition; transversion.

A review. As of today, a great amount of exptl. and theor. phenomenol. data have been collected in the literature according the mutagenic action of the classical mutagen – 2-aminopurine (2AP). However, so far they have not received proper explanation and substantiation. In this Opinion Piece, we provide an overview of recent progress in computational design and modeling of the physico-chem. mechanisms of the mutagenic action of 2AP. Results of quantum-chem. studies, aimed at the elucidation of the key microstructural mechanisms of the mutagenicity of 2AP, have been summarized here. In this context, for the first time it was outlined the most important surveys: Why 2AP is incorporated into DNA in trace concentrations? Whether classical mechanisms presented in the literature according the formation of the rare tautomers of canonical DNA bases work also for base analog – 2AP? In what way 2AP induces replication and incorporation errors? Whether the amino-imino tautomerisation of 2AP is related to its mutagenicity, that is whether the 2AP* rare tautomer is mutagenic? It is emphasized that the applied approach has a proper theor. substantiation, since it is based on our microstructural theory of the spontaneous point mutagenesis in DNA, and at the same time it accumulates scenarios of the origin of the induced point errors – transitions and transversions, which the classical Watson-Crick tautomeric hypothesis permits. Moreover, using author′s methodol., the profiles of the main physico-chem. characteristics for the tautomerisation reactions involving 2AP, which are integral parts of the biol. important tautomerically-conformational transformations, have been presented. Obtained results open new perspectives for prediction and design of the mutagenic derivatives of the nucleotide bases of any structure and origin before their synthesis and also for planning of new experiments and interpretation of the existing data. Abbreviations2AP2-AminopurineAadenineCcytosineDPTdouble proton transferGguanineIRCintrinsic reaction coordinateKPkey pointTthyminewwobbleWCWatson-CrickvdWvan der WaalsH-bondhydrogen bondCommunicated by Ramaswamy H. Sarma

Journal of Biomolecular Structure and Dynamics published new progress about DNA Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 452-06-2 belongs to class imidazoles-derivatives, and the molecular formula is C5H5N5, HPLC of Formula: 452-06-2.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Wu, Yunfei; Li, Jun; Yuan, Rui; Deng, Zihui; Wu, Xu published the artcile< Bone marrow mesenchymal stem cell-derived exosomes alleviate hyperoxia-induced lung injury via the manipulation of microRNA-425>, Quality Control of 6823-69-4, the main research area is microRNA425 PTEN TSG101 CD34 GW4869 hyperoxia induced lung injury; Bone marrow mesenchymal stem cell-derived exosomes; Hyperoxia-induced lung injury; PI3K/AKT signaling Pathway; PTEN; microRNA-425.

Hyperoxia-induced lung injury (HILI) is an acute lung injury (LI) induced by extended periods of exposure to hyperoxia. Alleviating LI by bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exos) and microRNAs (miRs) has been previously reported. This study is devised to probe the interaction between BMSCs-Exos and miR-425 in HILI. Firstly, BMSCs-Exos were isolated and identified. Then, HILI rat models and RLE-6TN cell models were successfully established and treated by BMSCs-Exos. Afterwards, functional assays were conducted to explore cell biol. behaviors in models, with miR-425 expression detected. Then, the target relation between miR-425 and PTEN was clarified by luciferase reporter assay. Eventually, expression of PTEN and the PI3K/Akt axis was assessed by Western blotting and qRT-PCR. BMSCs-Exos promoted miR-425 expression and attenuated HILI and H2O2 induced RLE-6TN cell injury as evidence by alleviated lung cell injury, decreased TUNEL-pos. cells, induced cell viability and declined apoptosis (all p < 0.05). Besides, when miR-425 was knocked-down, the protective role of BMSCs-Exos in HILI was also reduced (all p < 0.05). miR-425 targeted PTEN mRNA, whose upregulation reversed the protective role of BMSCs-Exos in HILI (all p < 0.05). BMSCs-Exos improved the quenched levels of the PI3K/AKT axis in HILI (all p < 0.05). Our data supported that miR-425 in BMSCs-Exos inhibits HILI by targeting PTEN and upregulating the PI3K/AKT axis. This study may provide personalized interventions for HILI remedy. Archives of Biochemistry and Biophysics published new progress about Adipogenesis. 6823-69-4 belongs to class imidazoles-derivatives, and the molecular formula is C30H30Cl2N6O2, Quality Control of 6823-69-4.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Xu, Xiaochen; Egger, Michaela; Chen, Hao; Bartosik, Karolina; Micura, Ronald published the artcile< Insights into xanthine riboswitch structure and metal ion-mediated ligand recognition>, Related Products of 452-06-2, the main research area is xanthine riboswitch NMT1 metal ion mediated ligand recognition.

Riboswitches are conserved functional domains in mRNA that mostly exist in bacteria. They regulate gene expression in response to varying concentrations of metabolites or metal ions. Recently, the NMT1 RNA motif has been identified to selectively bind xanthine and uric acid, resp., both are involved in the metabolic pathway of purine degradation Here, we report a crystal structure of this RNA bound to xanthine. Overall, the riboswitch exhibits a rod-like, continuously stacked fold composed of three stems and two internal junctions. The binding-pocket is determined by the highly conserved junctional sequence J1 between stem P1 and P2a, and engages a long-distance Watson-Crick base pair to junction J2. Xanthine inserts between a G-U pair from the major groove side and is sandwiched between base triples. Strikingly, a Mg2+ ion is inner-sphere coordinated to O6 of xanthine and a non-bridging oxygen of a backbone phosphate. Two further hydrated Mg2+ ions participate in extensive interactions between xanthine and the pocket. Our structure model is verified by ligand binding anal. to selected riboswitch mutants using isothermal titration calorimetry, and by fluorescence spectroscopic anal. of RNA folding using 2-aminopurine-modified variants. Together, our study highlights the principles of metal ion-mediated ligand recognition by the xanthine riboswitch.

Nucleic Acids Research published new progress about Crystal structure. 452-06-2 belongs to class imidazoles-derivatives, and the molecular formula is C5H5N5, Related Products of 452-06-2.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Peh, Guang-Rong; Kantchev, Eric Assen B.; Zhang, Chi; Ying, Jackie Y. published the artcile< N-Heterocycle carbene (NHC)-ligated cyclopalladated N,N-dimethylbenzylamine: A highly active, practical and versatile catalyst for the Heck-Mizoroki reaction>, SDS of cas: 1003-21-0, the main research area is palladium dimethylbenzylamine mesitylimidazolylidene catalyst Heck.

A protocol for the Heck-Mizoroki reaction mediated by cyclopalladated N,N-dimethylbenzylamine ligated with a N-heterocyclic carbene, 1,3-bis(mesityl)imidazol-2-ylidene (IMes), is reported. The precatalyst can be synthesized on ∼100 g scale by a tri-component, sequential, one-pot reaction of N,N-dimethylbenzylamine, PdCl2 and IMes·HCl in refluxing acetonitrile in air in the presence of K2CO3. This single component catalyst is stable to air, moisture and long term storage and can be conveniently dispensed as a stock solution in NMP. It mediates the Heck-Mizoroki reaction of a range of aryl and heteroaryl bromides in reagent grade NMP at the 0.1-2 mol% range without the need for rigorous anhydrous techniques or a glove box, and is active even in air. The catalyst is capable of achieving very high levels of catalytic activity (TON of up to 5.22 × 105) for the coupling of a deactivated aryl bromide, p-bromoanisole, with tert.-Bu acrylate as a benchmark substrate pair. A wide range of aryl bromides, iodides and, for the first time with a NHC-Pd catalyst, a triflate was coupled with diverse acrylate derivatives (nitrile, tert-Bu ester and amides) and styrene derivatives The use of excess (>2 equivalent) of the aryl bromide and tert-Bu acrylate leads to mixture of tert-Bu β,β-diarylacrylate and tert-Bu cinnamate derivatives depending on the substitution pattern of the aryl bromide. Electron rich m- and p-substituted aryl bromides give the diarylated products exclusively, whereas electron-poor aryl bromides give predominantly mono-arylated products. For o-substituted aryl bromides, no doubly arylated products could be obtained under any conditions. Overall, the active catalyst (IMes-Pd) shows higher activity with electron-rich aryl halides, a marked difference compared with the more commonly used phosphane-Pd or non-ligated Pd catalysts.

Organic & Biomolecular Chemistry published new progress about Heck reaction. 1003-21-0 belongs to class imidazoles-derivatives, and the molecular formula is C4H5BrN2, SDS of cas: 1003-21-0.

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem