Suppressing LncRNA HOXA-AS3 by CRISPR-dCas9 inhibits pancreatic cancer development.

The lncRNA HOXA-AS3 has been reported as a potential oncogene in tumors. Nevertheless, the molecular mechanism of HOXA-AS3 in pancreatic cancer (PC) progression remains unknown. We performed quantitative real-time (qRT) PCR assay to detect the expression levels of HOXA-AS3, miR-29c in PC specimens. Then, we transfected sgRNA-HOXA-AS3, miR-29c mimics, miR-29c inhibitors, or vector-CDK6 plasmids into PC cell lines to regulate the expression levels of HOXA-AS3, miR-29c or CDK6. Luciferase reporter assay was performed to identify the correlations among miR-29c, HOXA-AS3 and 3' UTR of CDK6.The ability of cell proliferation was assessed by cell counting and subcutaneous tumor growth assay. HOXA-AS3 level was upregulated in PC, and its knockdown suppressed PC cells proliferation, whereas miR-29c antagonized the regulatory effect of HOXA-AS3 knockdown by directly binding to HOXA-AS3.Moreover, CDK6 was a target of miR-29c and miR-29c exerted anti-proliferation effects through inhibiting CDK6. HOXA-AS3 could accelerate the growth of PC cells partially by regulating the miR-29c/CDK6 axis, which could be used as a potential therapeutic target in CRISPR-mediated PC treatment.

Insight into the modulation of Shaw2 Kv channels by general anesthetics: structural and functional studies of S4-S5 linker and S6 C-terminal peptides in micelles by NMR.

The modulation of the Drosophila Shaw2 Kv channel by 1-alkanols and inhaled anesthetics is correlated with the involvement of the S4-S5 linker and C-terminus of S6, and consistent with stabilization of the channel's closed state. Structural analysis of peptides from S4-S5 (L45) and S6 (S6c), by nuclear magnetic resonance and circular dichroism spectroscopy supports that an α-helical conformation was adopted by L45, while S6c was only in an unstable/dynamic partially folded α-helix in dodecylphosphocholine micelles. Solvent accessibility and paramagnetic probing of L45 revealed that L45 lies parallel to the surface of micelles with charged and polar residues pointing towards the solution while hydrophobic residues are buried inside the micelles. Chemical shift perturbation introduced by 1-butanol on residues Gln320, Thr321, Phe322 and Arg323 of L45, as well as Thr423 and Gln424 of S6c indicates possible anesthetic binding sites on these two important components in the channel activation apparatus. Diffusion measurements confirmed the association of L45, S6c and 1-butanol with micelles which suggests the capability of 1-butanol to influence a possible interaction of L45 and S6c in the micelle environment.

The concerted contribution of the S4-S5 linker and the S6 segment to the modulation of a Kv channel by 1-alkanols.

Gating of voltage-gated K(+) channels (K(v) channels) depends on the electromechanical coupling between the voltage sensor and activation gate. The main activation gate of K(v) channels involves the COOH-terminal section of the S6 segment (S6-b) and the S4-S5 linker at the intracellular mouth of the pore. In this study, we have expanded our earlier work to probe the concerted contribution of these regions to the putative amphipathic 1-alkanol site in the Shaw2 K(+) channel. In the S4-S5 linker, we found a direct energetic correlation between alpha-helical propensity and the inhibition of the Shaw2 channel by 1-butanol. Spectroscopic structural analyses of the S4-S5 linker supported this correlation. Furthermore, the analysis of chimeric Shaw2 and K(v)3.4 channels that exchanged their corresponding S4-S5 linkers showed that the potentiation induced by 1-butanol depends on the combination of a single mutation in the S6 PVPV motif (PVAV) and the presence of the Shaw2 S4-S5 linker. Then, using tandem-heterodimer subunits, we determined that this potentiation also depends on the number of S4-S5 linkers and PVAV mutations in the K(v) channel tetramer. Consistent with the critical contribution of the Shaw2 S4-S5 linker, the equivalent PVAV mutation in certain mammalian K(v) channels with divergent S4-S5 linkers conferred weak potentiation by 1-butanol. Overall, these results suggest that 1-alkanol action in Shaw2 channels depends on interactions involving the S4-S5 linker and the S6-b segment. Therefore, we propose that amphiphilic general anesthetic agents such as 1-alkanols may modulate gating of the Shaw2 K(+) channel by an interaction with its activation gate.

[Study on application of hazard analysis and critical control point in rural water supply system].

OBJECTIVE: To study the feasibility and effect of the HACCP application in rural water supply systems. The Tucheng water supply system (TWSS) in Hebei Province was selected as study field. METHODS: The hazard analysis and evaluation were developed according to WHO/FAO "HACCP System and Guidelines for its Application" and WHO "Guidelines for drinking water quality". RESULTS: The CCP was found and the control measures were established based on hazard analysis. The present study showed that the CCP could be found in all steps of the water supply system. After the HACCP application in TWSS, no distinct improvement of water quality was observed, but the occupational technical knowledge score of the staff was improved from 75.2 to 86.6. CONCLUSION: The results indicated that as a risk management tool, application of HACCP in rural water supply system is feasible.