[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

J. Appl. Cryst.の発刊に際して

Yuming Yang,†,§ Qiang Zhao,‡,§ Wei Feng,† and Fuyou Li*,† †Department of Chemistry and State Key Laboratory of Molecular Engineering of Polymers and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, P. R. China ‡Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, Nanjing 210046, P. R. China.

Luminescent chemodosimeters for bioimaging.

: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Recently, more than 1000 large intergenic noncoding RNAs (lincRNAs) have been reported. These RNAs are evolutionarily conserved in mammalian genomes and thus presumably function in diverse biological processes. Here, we report the identification of lincRNAs that are regulated by p53. One of these lincRNAs (lincRNA-p21) serves as a repressor in p53-dependent transcriptional responses. Inhibition of lincRNA-p21 affects the expression of hundreds of gene targets enriched for genes normally repressed by p53. The observed transcriptional repression by lincRNA-p21 is mediated through the physical association with hnRNP-K. This interaction is required for proper genomic localization of hnRNP-K at repressed genes and regulation of p53 mediates apoptosis. We propose a model whereby transcription factors activate lincRNAs that serve as key repressors by physically associating with repressive complexes and modulate their localization to sets of previously active genes.

A Large Intergenic Noncoding RNA Induced by p53 Mediates Global Gene Repression in the p53 Response

A new imidazo[1,5-a]pyridine-based pH fluorescent probe has been synthesized and characterized. It is the first time that imidazo[1,5-a]pyridine is used as a fluorescent probe. This probe responds to acidic pH with fast response (within 3 min), high selectivity and sensitivity. It has good reversibility and nearly no interference from common metal ions. The probe is suitable for acidic conditions and can quantitatively detect pH value based on the equilibrium equation, pH = pKa − log[(Ia − Ix)/(Ix − Ib)], with a good linear relationship. Moreover, we verified that the protonation of the 2-nitrogen in the imidazole decreases the electron density on the fused ring by 1H NMR analysis and DFT calculation. We proposed that intramolecular charge transfer and solvation of the probe in aqueous solutions might be the mechanism of the fluorescence enhancement under strongly acidic conditions.

A new fluorescent pH probe for acidic conditions

A quick response fluorescent probe based on coumarin and quinone for glutathione and its application in living cells.

A new ICT/FRET platform composed of coumarin-hemicyanine dyad was rationally designed for ratiometric fluorescent probes. The platform could concert the spectral overlap and the emission shifts by changing ICT donor. The mitochondria-targeting probe was developed to sense endogenous sulfite in living cells with high selectivity, sensitivity and fast response.

A rational design of ratiometric fluorescent probes based on new ICT/FRET platform and imaging of endogenous sulfite in living cells

A new fluorescent probe based on the cleavage of disulfide bond and subsequent intramolecular cyclization process was designed for the detection of H 2 S. The selectivity was guaranteed by use of the unique nucleophilicity of H 2 S. The impacts of biological thiols were neglectable and biological thiols could lead to a fluorescence emission band different from H 2 S with longer response time. The probe was also applied to detect H 2 S in living cells successfully.

A ratiometric fluorescent probe for fast detection of hydrogen sulfide and recognition of biological thiols

A new FRET-based ratiometric fluorescence probe for hypochlorous acid was developed. The FRET platform was constructed by a coumarin moiety as the energy donor and (E)-4-(4-(dialkylamino)styryl)-1-methylpyridin-1-ium iodide as the energy acceptor in which double bonds was recognition group for hypochlorous acid. Significantly, the water-soluble probe showed good selectivity, sensitivity, and lower detection limit (89 nM) for hypochlorous acid in optimal working condition. Moreover, the probe with good photo-stability and lower toxicity could successfully detect exogenous and endogenous hypochlorous acid and target mitochondria in living cells.

Bao-Xiang Zhao

Papers

A new fluorescent pH probe for acidic conditions

A quick response fluorescent probe based on coumarin and quinone for glutathione and its application in living cells.

A rational design of ratiometric fluorescent probes based on new ICT/FRET platform and imaging of endogenous sulfite in living cells

A ratiometric fluorescent probe for fast detection of hydrogen sulfide and recognition of biological thiols

A new water-soluble and mitochondria-targeted fluorescence probe for ratiometric detection of hypochlorous acid in living cells