Related Experiment Video

Updated: Jun 25, 2026

Monitoring Protein-RNA Interaction Dynamics In Vivo at High Temporal Resolution Using χCRAC
09:15

Monitoring Protein-RNA Interaction Dynamics In Vivo at High Temporal Resolution Using χCRAC

Published on: May 9, 2020

Interruption of RNA processing machinery by a small compound, 1-[(4-chlorophenyl)methyl]-1H-indole-3-carboxaldehyde

Wei Guo1, Shuhong Wu, Li Wang

  • 1Department of Thoracic and Cardiovascular Surgery, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.

Molecular Cancer Therapeutics
|February 12, 2009
PubMed

Insights

Oncrasin-1 selectively kills K-Ras cancer cells by disrupting RNA processing. This drug causes protein kinase Ciota (PKCiota) to aggregate with splicing factors, suppressing RNA transcription and affecting cell function.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Oncogenic Ras proteins activate protein kinase Ciota (PKCiota), crucial for K-Ras-induced transformation and carcinogenesis.
  • The precise role of PKCiota in signal transduction and oncogenesis remains unclear.
  • A novel small molecule, oncrasin-1, selectively eliminates K-Ras mutant cancer cells.

Purpose of the Study:

  • To elucidate the causes and biological consequences of PKCiota nuclear aggregation induced by oncrasin-1.
  • To investigate the impact of oncrasin-1 on DNA repair and RNA processing pathways.
  • To determine the mechanism by which oncrasin-1 affects K-Ras mutant cancer cells.

Main Methods:

  • Treatment of K-Ras mutant cancer cells with oncrasin-1.
  • Analysis of protein aggregation, including PKCiota and splicing factors.
  • Assessment of DNA repair proteins (Rad51) and RNA polymerase II phosphorylation.
  • Evaluation of reporter gene expression and protein-protein interactions.

Main Results:

  • Oncrasin-1 induced coaggregation of PKCiota and splicing factors into megaspliceosomes.
  • No significant effect on the DNA repair molecule Rad51 was observed.
  • Suppression of RNA polymerase II phosphorylation and reporter gene expression in sensitive cells.
  • Oncrasin-1 disrupted the interaction between PKCiota and the CDK9/cyclin T1 complex.

Conclusions:

  • Oncrasin-1 suppresses RNA transcription by interfering with RNA processing machinery.
  • PKCiota plays a role in the biological function of RNA processing complexes.
  • Oncrasin-1 represents a potential therapeutic strategy targeting K-Ras mutant cancers by disrupting RNA processing.

More Related Videos

Chemical Inactivation of the E3 Ubiquitin Ligase Cereblon by Pomalidomide-based Homo-PROTACs10:44

Chemical Inactivation of the E3 Ubiquitin Ligase Cereblon by Pomalidomide-based Homo-PROTACs

Published on: May 15, 2019

Dual CRISPR-Interference Strategy for Targeting Synthetic Lethal Interactions Between Non-Coding RNAs in Cancer Cells07:23

Dual CRISPR-Interference Strategy for Targeting Synthetic Lethal Interactions Between Non-Coding RNAs in Cancer Cells

Published on: May 30, 2025

Related Concept Videos

Experimental RNAi02:15

Experimental RNAi

RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
siRNA - Small Interfering RNAs02:30

siRNA - Small Interfering RNAs

Small interfering RNAs, or siRNAs, are short regulatory RNA molecules that can silence genes post-transcriptionally, as well as the transcriptional level in some cases. siRNAs are important for protecting cells against viral infections and silencing transposable genetic elements.
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
Chromatin Structure Regulates pre-mRNA Processing02:41

Chromatin Structure Regulates pre-mRNA Processing

In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
Types of RNA01:20

Types of RNA

Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in regulating gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA Performs Diverse...