Sequence-specific targeting of RNA.

Post-transcriptional modifications play an important role in several processes, including translation, splicing, and RNA degradation in eukaryotic cells. To investigate the function of specific modifications it is of high interest to develop tools for sequence-specific RNA-targeting. This work focuses on two abundant modifications of eukaryotic mRNA, namely methylation of the guanine-N7 position of the 5'-cap and internal N-methyladenosine (mA).

Nucleoside-modified AdoMet analogues for differential methyltransferase targeting.

Methyltransferases (MTases) modify a wide range of biomolecules using S-adenosyl-l-methionine (AdoMet) as the cosubstrate. Synthetic AdoMet analogues are powerful tools to site-specifically introduce a variety of functional groups and exhibit potential to be converted only by distinct MTases. Extending the size of the substituent at the sulfur/selenium atom provides selectivity among MTases but is insufficient to discriminate between promiscuous MTases.

Sequence-specific mA demethylation in RNA by FTO fused to RCas9.

-methyladenosine (mA) is the most common internal modification in eukaryotic mRNA and associated with numerous cellular processes in health and disease. Up- and down-regulation of its "writer" or "eraser" proteins alter the global mA level; however, modifying distinct mA sites has remained elusive. We genetically fused the dioxygenase FTO responsible for mA demethylation to RCas9 as an RNA-targeting module.

Making the Message Clear: Concepts for mRNA Imaging.

The transcriptome of each individual cell contains numerous RNA species, each of which can be controlled by multiple mechanisms during their lifetime. The standard transcriptome analysis focuses on the expression levels of the genes of interest. To gain additional insights into spatiotemporal RNA distribution and the underlying trafficking processes, RNA labeling and imaging are necessary-ideally in living cells.

Fragmentation of the CRISPR-Cas Type I-B signature protein Cas8b.

Background: CRISPR arrays are transcribed into long precursor RNA species, which are further processed into mature CRISPR RNAs (crRNAs). Cas proteins utilize these crRNAs, which contain spacer sequences that can be derived from mobile genetic elements, to mediate immunity during a reoccurring virus infection. Type I CRISPR-Cas systems are defined by the presence of different Cascade interference complexes containing large and small subunits that play major roles during target DNA selection.

CRISPR/Cas9: A New Tool for RNA Imaging in Live Cells.

Cas9 can be implemented as an RNA-targeting system to track mRNA in living cells. Nuclear export is enabled by efficient targeting of GFP-fused Cas9 to an endogenous mRNA. The approach provides a new and versatile platform for RNA-targeting with applications in RNA imaging and beyond.

Safety of the Ullorex oral intragastric balloon for the treatment of obesity.

Background: Intragastric balloons have been used for weight loss with varying success. Widespread use of intragastric balloons has been limited because balloons must be placed in, and removed from, the stomach endoscopically. Development of a balloon that does not require endoscopy suggests that obesity treatment with intragastric balloons is feasible.