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Biology subjects

Winczura, K.

Publications and source records attributed to Winczura, K..

3 recordsLinked to original sources

Antisense oligonucleotides targeting transcription termination windows disrupt mRNA 3' end processing and decrease gene expression

Antisense oligonucleotides (ASOs) are short, synthetic nucleic acids that bind to complementary RNA sequences and alter gene expression, making them versatile therapeutic agents. Here, we identify transcription termination windows of protein-coding genes as previously unrecognized targets for ASOs. We show that ASOs can act on nascent RNA synthesised downstream of the annotated genes, leading to a pronounced decrease in the corresponding mRNA levels. These downstream-of-gene ASOs (DG-ASOs) induce RNase H1-dependent cleavage, impairing mRNA 3 end processing, directing the unprocessed mRNAs for exosome-dependent degradation and creating early entry points in the nascent RNA for the XRN2 exonuclease termination factor. Altogether, we show that termination windows are genuine ASO targets which can be exploited to suppress gene expression. Importantly, we also reveal an underappreciated source of off-target effects which may arise from ASOs binding downstream of genes. Our findings indicate the necessity to expand ASO design and off-target assessment guidelines to include termination window sequences, thereby improving therapeutic efficacy and safety.

molecular biology↗

RPRD Proteins Control Transcription in Human Cells

The regulation of transcription is an essential process that allows the cell to respond to various internal and external signals. RNA Polymerase II (Pol II) activity is controlled by a number of factors which bind to the C-terminal domain (CTD) of its largest subunit, RPB1, and stimulate or suppress RNA synthesis. Here, we demonstrate that CTD-interacting proteins, RPRD2, RPRD1B and RPRD1A act as negative regulators of transcription and their levels inversely correlate with the accumulation of nascent and newly transcribed RNA in human cells. We show that the RPRD proteins form mutually exclusive complexes with Pol II to coordinate their roles in transcriptional control. Our data indicate that RPRD2 exerts the most substantial impact on transcription and has the potential to alter key biological processes including the cellular stress response and cell growth.

molecular biology↗

Supramolecular cylinders target bulge structures in the 5-prime UTR of the RNA genome of SARS-CoV-2 and inhibit viral replication

The untranslated regions (UTRs) of viral genomes contain a variety of conserved yet dynamic structures crucial for viral replication, providing drug targets for the development of broad spectrum anti-virals. We combine in vitro RNA analysis with Molecular Dynamics simulations to build the first 3D models of the structure and dynamics of key regions of the 5 UTR of the SARS-CoV-2 genome. Furthermore, we determine the binding of metallo-supramolecular helicates (cylinders) to this RNA structure. These nano-size agents are uniquely able to thread through RNA junctions and we identify their binding to a 3-base bulge and the central cross 4-way junction located in the stem loop 5. Finally, we show these RNA-binding cylinders suppress SARS-CoV-2 replication, highlighting their potential as novel antiviral agents.

biochemistry↗