Piwi like RNA-mediated gene silencing 1 gene as a possible major player in gastric cancer

AIM To establish a permanent piwi like RNA-mediated genesilencing 1(PIWIL1) gene knockout in AGP01 gastric cancer cell line using CRISPR-Cas9 system and analyze phenotypic modifications as well as gene expression alterations.METHODS CRISPR-Cas9 system used was purchased from Dharmacon GE Life Sciences(Lafayette, CO, United States) and permanent knockout was performed according to manufacturer's recommendations. Woundhealing assay was performed to investigate the effect of PIWIL1 knockout on migration capability of cells and Boyden chamber invasion assay was performed to investigate the effect on invasion capability. For the gene expression analysis, a one-color microarray-based gene expression analysis kit(Agilent Technologies, Santa Clara, CA, United States) was used according to the protocol provided by the manufacturer. RESULTS PIWIL1 gene knockout caused a significant decrease in AGP01 migration capacity as well as a significant decrease in cell invasiveness. Moreover, functional analysis based on grouping of all differentially expressed m RNAs identified a total of 35 genes(5 up-regulated and 30 down-regulated) encoding proteins involved in cellular invasion and migration. According to current literature, 9 of these 35 genes(DOCK2, ZNF503, PDE4 D, ABL1, ABL2, LPAR1, SMAD2, WASF3 and DACH1) are possibly related to the mechanisms used by PIWIL1 to promote carcinogenic effects related to migration and invasion, since their functions are consistent with the changes observed(being up-or down-regulated after knockout). CONCLUSION Taken together, these data reinforce the idea that PIWIL1 plays a crucial role in the signaling pathway of gastric cancer, regulating several genes involved in migration and invasion processes; therefore, its use as a therapeutic target may generate promising results in the treatment of gastric cancer.

Effect of cDNA fragments in different length derived from Potato Virus Y coat protein gene on the induction of RNA-mediated virus resistance

We have reported that cDNA derived from entire coat protein (CP) gene of potato virus Y (PVY) could induce resistance to PVY infection in transgenic tobacco plants, and the resistance was further demonstrated to be RNA-mediated rather than coat protein-mediated. In this study, we cloned cDNA fragments of 202 bp, 417 bp, and 603 bp in length derived from the 3′ end of the PVY CP gene, and the cDNA fragments were introduced into tobacco (var. NC89) plants via Agrobacterium-mediated transformation system. The results of resistance assay showed that the CP cDNA fragments of 417 bp and 603 bp could confer resistance of the trans-genic plants to PVY infection, but the fragment of 202 bp in length could not. Molecular analysis revealed that the resistance was RNA-mediated, which is believed to be a result of post-transcriptional gene silencing. The results indicate that the length of cDNA fragments needed for resistance induction was located somewhere between 202 bp and 417 bp from the 3′ end of PVY CP gene.

Blocking Translation of Oncogenic mRNA

Double-stranded RNA-mediated interference (RNAi), antisense oligonucleotides (ASO), and ribozymes have excellent specificity to their target oncogenic mRNA. They also seem to show great promise when it comes to treating cancer. The problem is that RNAi, ASO, and ribozymes have poor stability and are constantly being degraded by nucleases. Researchers have made some efforts to increase antisense oligonucleotides’ stability by creating phospharimidate and Phosphorothioate. Currently, ribozymes, antisense oligonucleotides, and (RNAi) are the three main methods used to target RNA. These methods are currently undergoing clinical trials for the purpose of focusing on specific RNAs involved in disorders like cancer and neurodegeneration. In fact, ASOs that target amyotrophic lateral sclerosis and spinal muscular atrophy have produced promising results in clinical trials. The formation of chemical alterations that boost affinity and selectivity while reducing noxiousness owing to off-target impacts are two benefits of ASOs. Another benefit is increased affinity. With a focus on RNAi and ASOs, this review illustrated the main therapeutic strategies of RNA therapy now in use.

New horizons of regulatory RNA

Genetic information flows from DNA to protein through RNA in the central dogma.Different RNA species are known to accomplish essential tasks of protein encoding(mRNAs),amino acid loading(tRNAs),and translation machinery assembly(rRNAs).However,on top of these well-known roles,RNAs are central to various cellular regulatory pathways.Here we summarize newly emerging regulatory functions of RNA,specifically focusing on regulations through RNA modifications,RNP granules,and chromatin-associated regulatory RNA.In addition to being an essential building block of the central dogma,RNA can be critical to the regulation of many cellular processes.

Silence of Synaptotagmin VII inhibits release of dense core vesicles in PC12 cells

Synaptotagmin VII (Syt VII), which has a higher Ca2+ affinity and slower disassembly kinetics with lipid than Syt I and Syt IX, was regarded as being uninvolved in synaptic vesicle (SV) exocytosis but instead possibly as a calcium sensor for the slower kinetic phase of dense core vesicles (DCVs) release. By using high temporal resolution capacitance and amperometry measurements, it was demonstrated that the knockdown of endogenous Syt VII attenuated the fusion of DCV with the plasma membrane, reduced the amplitude of the exocytotic burst of the Ca2+-triggered DCV release without affecting the slope of the sustained component, and blocked the fusion pore expansion. This suggests that Syt VII is the Ca2+ sensor of DCV fusion machinery and is an essential factor for the establishment and maintenance of the pool size of releasable DCVs in PC12 cells.