9 research outputs found
CtIP is a protein target of miR-335.
<p>(A) Diagram illustrating the putative miR-335 binding site in the 3′UTR of <i>CtIP</i>. The miR-335 seed sequence is boxed. (B) <i>CtIP</i> 3′UTR luciferase reporter assay indicated downregulation of luciferase activity after overexpression of miR-335 in HeLa cells using luciferase reporter constructs containing the WT 3′UTR of the <i>CtIP</i> gene. This downregulation in luciferase activity was not observed with the reporter construct containing a mutated version of the 3′UTR of CtIP with a deletion of 6-nucleotide miR-335 ‘seed’ sequence (Δ6). (C) Immunoblot of nuclear and cytoplasmic lysates from HeLa cells indicating reductions in CtIP protein levels after overexpression of miR-335. The fold change of CtIP is shown below the blot after normalization to KAP1, a loading control. (D) RT-qPCR results of <i>CtIP</i> transcript levels with miR-CTL and miR-335 overexpression in HeLa cells. Expression levels were normalized to <i>GAPDH</i> expression as an internal control.</p
Luminescent Coordination Polymers for Highly Sensitive Detection of Nitrobenzene
Three new luminescent coordination
polymers (CPs), [Ag<sub>2</sub>(bpp)Â(Hsba)]·H<sub>2</sub>O (<b>1</b>), [CdÂ(bpp)Â(Hsba)·H<sub>2</sub>O] (<b>2</b>), and [PbÂ(bpp)<sub>3</sub>Â(H<sub>2</sub>sba)<sub>2</sub>] (<b>3</b>) (bpp = 1,3-bisÂ(4-pyridyl)Âpropane,
H<sub>3</sub>sba = 2,4-dichloro-5-sulfamoylbenzoic acid), have been
designed and synthesized by hydrothermal methods. Compound <b>1</b> exhibits left- and right-handed helical chains. Compound <b>2</b> shows a 2-fold parallel interpenetration <b>sql</b> net with
4<sup>4</sup>·6<sup>2</sup> topology. Compound <b>3</b> displays a supramolecular wavelike chain. These three title CPs
are used as fluorescence sensors for highly selective and sensitive
detection of nitrobenzene in a wide linear detection range
Obtaining Chiral Metal–Organic Frameworks via a Prochirality Synthetic Strategy with Achiral Ligands Step-by-Step
Although
some achievements of constructing chiral metal–organic frameworks
(MOFs) with diverse achiral ligands have been made, there is still
a lack of full understanding of the origin and formation mechanism
of chirality, as well as the reasonable principles for the design
and construction of chiral frameworks. The concept of prochirality
in organic molecules and complex systems inspires us to explore the
synthetic strategy of chiral MOFs based on achiral sources. Here,
an achiral compound [CuÂ(en)]Â[(VO<sub>3</sub>)<sub>2</sub>] (<b>1</b>) was isolated in the CuCl<sub>2</sub>/NH<sub>4</sub>VO<sub>3</sub>/en system, while further chiral frameworks [CuÂ(en)Â(Im)<sub>2</sub>]Â[(VO<sub>3</sub>)<sub>2</sub>] (<b>2a</b> and <b>2b</b>) were obtained by the reaction between compound <b>1</b> and another achiral ligand Im (ethanediamine = en and imidazole
= Im). In the present system, compound <b>1</b> has the characteristic
of a quasi-plane structure unit. Further reaction of compound <b>1</b> and the achiral ligand (Im) induced the formation of chiral
Λ/Δ Cu centers, and then a pair of chiral frameworks containing
one-dimensional (1D) helical chains was formed. The chiral symmetry
breaking phenomenon of compounds <b>2a</b> and <b>2b</b> can also be expected and explained based on this kind of prochirality
synthetic strategy
MiR335-induced DDR defects were abrogated in RS7 and RS73 after AMO-miR-335 treatment.
<p>(A) Partial restoration of BRCA1-IRIFs 8 hours post-12 Gy in constitutively miR-335 overexpressing RS7 and RS73 LCLs following AMO-miR-335 exposure (+). The (−) denotes similar treatment with AMO-CTL. RS67 is deficient for RNF168 and does not form stable BRCA1-IRIFs <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003505#pgen.1003505-Devgan1" target="_blank">[27]</a>; it was used as a negative control for BRCA1-IRIFs in these experiments. (B) Treatment with AMO-miR-335(+) partially corrected the reduced colony survival, a ‘radiosensitive’ cellular phenotype, after 1 Gy IR in RS7 and RS73. The RS cutoff is based on previous optimizations <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003505#pgen.1003505-Sun1" target="_blank">[23]</a>.</p
ATM–dependent downregulation of miR-335 post-IR.
<p>(A) RT-qPCR indicates downregulation of miR-335 expression 2 hours after 10 Gy in WT but not A-T LCLs. (B) MiR-335 downregulation following IR- or doxorubicin-induced DNA damage by RT-qPCR in MCF7 (ATM +/+) cells. (C) Inhibition of ATM kinase activity in MCF7 cells with KU-55933 for 2 hours prior to IR exposure abolishes the downregulation of miR-335 expression 2 hours after IR. (D) MiR-335 is located in the second intron of <i>MEST</i>. The arrows indicate two predicted CREB binding sites in the <i>MEST</i> promoter (−938 to −949, −214 to −216 related to translational start site, respectively). (E) RT-qPCR shows that transcription levels of <i>MEST</i> mimic those of miR-335 in response to IR, supporting their anticipated co-regulation. (F) Suppression of CREB by siRNA reduced endogenous miR-335 levels and abolished the post-IR down-regulation of miR-335 observed in siCTL transfected HeLa cells. (G) Results of CREB ChIP assay 2 hours post-IR in HeLa cells indicated the binding of CREB to the <i>MEST</i> promoter before IR and release from the promoter after IR.</p
DDR defects induced by miR-335 overexpression in HeLa cells.
<p>(A) RDS (radioresistant DNA synthesis): miR-CTL and miR-335 overexpressing HeLa cells were treated with or without 10 Gy IR and S-phase DNA synthesis was labeled with BrdU. The percent change of BrdU incorporation (+IR/−IR) was summarized from three independent experiments. MiR-CTL overexpressing HeLa cells showed a reduction (42%) in the percentage of BrdU incorporation whereas miR-335 overexpressing HeLa cells showed less of a reduction (16%). The * indicates p<0.05. (B) NCA (neutral comet assay): quantification of DNA repair with the NCA indicates reduced DNA repair at 5 hours after 15 Gy in HeLa cells overexpressing miR-335. Three independent experiments were performed; the * indicates p<0.05. (C) BRCA1 foci: immunofluorescent staining of HeLa cells after 12 Gy IR with BRCA1 showed a foci-forming defect in miR-335 overexpressing cells (bars 7 and 11). This response was reversed and corrected in miR-335 overexpressing cells co-transfected with CtIP lacking the 3′UTR (Δ3′UTR) (bar 15). The * indicates intra-sample Student's t-test (p<0.05) comparing the indicated bar with the non-IR condition. ** indicates inter-sample Student's t-test (p<0.05) comparing the 8 hour time points between samples. (D) CSA (clonogenic survival assay): reduced colony survival in miR-335 overexpressing HeLa cells post-IR. The survival fraction was significantly improved when CtIP (Δ3′UTR) was added back to miR-335 overexpressing HeLa cells. The radiation dose used for all samples is 0, 2, and 5 Gy. The x-axis has been offset for each pair of data points to make viewing the data and error bars easier. The * indicates p<0.05.</p
MiR-335 was constitutively overexpressed in RS7 and RS73 LCLs.
<p>(A) RT-qPCR indicating >10-fold increases in miR-335 expression in RS7 and RS73 LCLs when compared to WT and A-T LCL controls. Three different WT LCLs were used in RT-qPCR experiments and were used to normalize the expression values for A-T, RS7, and RS73 LCLs. (B) Immunoblotting of cytoplasmic and nuclear lysates isolated from RS7 cells with or without 10 Gy IR indicated reductions in CtIP protein levels. Two bands were noted, representing modified and unmodified CtIP. (C) Treatment of RS7, RS73 and MCF7 cells (also miR-335 overexpressing) with AMO-miR-335 increased nuclear CtIP protein levels compared to WT and AT cells. The quantification of CtIP is shown below the blot after normalization to the loading control.</p
Metal-Mediated Controllable Creation of Secondary, Tertiary, and Quaternary Carbon Centers: A Powerful Strategy for the Synthesis of Iron, Cobalt, and Copper Complexes with in Situ Generated Substituted 1‑Pyridineimidazo[1,5‑<i>a</i>]pyridine Ligands
An efficient strategy for the synthesis of a wide variety
of coordination
complexes has been developed. The synthetic protocol involves a solvothermal
in situ metal–ligand reaction of picolinaldehyde, ammonium
acetate, and transition-metal ions, leading to the generation of 12
coordination complexes supported by a novel class of substituted 1-pyridineimidazoÂ[1,5-<i>a</i>]Âpyridine ligands (<b>L1</b>–<b>L5</b>). The ligands <b>L1</b>–<b>L5</b> were afforded
by metal-mediated controllable conversion of the aldehyde group of
picolialdehyde into a ketone and secondary, tertiary, and quaternary
carbon centers, respectively. Complexes of various nuclearities were
obtained: from mono-, di-, and tetranuclear to 1D chain polymers.
The structures of the in situ formed complexes could be controlled
rationally via the choice of appropriate starting materials and tuning
of the ratio of the starting materials. The plausible mechanisms for
the formation of the ligands <b>L1</b>–<b>L5</b> were proposed
Metal-Mediated Controllable Creation of Secondary, Tertiary, and Quaternary Carbon Centers: A Powerful Strategy for the Synthesis of Iron, Cobalt, and Copper Complexes with in Situ Generated Substituted 1‑Pyridineimidazo[1,5‑<i>a</i>]pyridine Ligands
An efficient strategy for the synthesis of a wide variety
of coordination
complexes has been developed. The synthetic protocol involves a solvothermal
in situ metal–ligand reaction of picolinaldehyde, ammonium
acetate, and transition-metal ions, leading to the generation of 12
coordination complexes supported by a novel class of substituted 1-pyridineimidazoÂ[1,5-<i>a</i>]Âpyridine ligands (<b>L1</b>–<b>L5</b>). The ligands <b>L1</b>–<b>L5</b> were afforded
by metal-mediated controllable conversion of the aldehyde group of
picolialdehyde into a ketone and secondary, tertiary, and quaternary
carbon centers, respectively. Complexes of various nuclearities were
obtained: from mono-, di-, and tetranuclear to 1D chain polymers.
The structures of the in situ formed complexes could be controlled
rationally via the choice of appropriate starting materials and tuning
of the ratio of the starting materials. The plausible mechanisms for
the formation of the ligands <b>L1</b>–<b>L5</b> were proposed