Related Experiment Video

Updated: Feb 9, 2026

A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1
11:25

A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1

Published on: March 18, 2017

10.0K

An anionic phthalocyanine decreases NRAS expression by breaking down its RNA G-quadruplex

Keiko Kawauchi1, Wataru Sugimoto2, Takatoshi Yasui2

  • 1Faculty of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe, 650-0047, Japan. kawauchi@center.konan-u.ac.jp.

Nature Communications
|June 13, 2018
PubMed

Insights

Researchers developed ZnAPC, a photosensitizer that targets NRAS mRNA. Photo-irradiation with ZnAPC selectively degrades NRAS mRNA, reducing cancer cell viability, offering a new approach for cancer therapy.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cancer Research

Background:

  • Aberrant RAS signaling pathways drive aggressive cancer phenotypes.
  • RAS-targeted therapies show promise but face challenges due to RAS protein structural complexity.
  • NRAS is a key RAS isoform implicated in cancer progression.

Purpose of the Study:

  • To investigate the potential of ZnAPC, an anionic phthalocyanine, to control NRAS expression via photo-irradiation.
  • To explore ZnAPC's mechanism of targeting NRAS mRNA for therapeutic intervention.
  • To evaluate the efficacy of ZnAPC-mediated photodynamic therapy in reducing cancer cell viability.

Main Methods:

  • In vitro binding assays of ZnAPC with NRAS mRNA G-quadruplex structures.
  • Assessment of ZnAPC's selectivity for NRAS mRNA G-quadruplexes in the presence of cellular RNA.
  • Photo-irradiation experiments to induce selective RNA cleavage and assess downstream effects.
  • Measurement of NRAS mRNA and protein levels following ZnAPC treatment and photo-irradiation.
  • Evaluation of cancer cell viability after treatment.

Main Results:

  • ZnAPC selectively binds to a G-quadruplex-forming oligonucleotide in the 5'-untranslated region of NRAS mRNA.
  • ZnAPC binding and subsequent photo-irradiation lead to selective cleavage of the target NRAS mRNA G-quadruplex.
  • Photo-irradiation with ZnAPC significantly decreases NRAS mRNA and NRAS protein expression in cancer cells.
  • Reduced NRAS expression resulted in decreased cancer cell viability.

Conclusions:

  • ZnAPC acts as a photosensitizer to control NRAS expression by targeting its mRNA.
  • The selective binding and photo-cleavage mechanism offers a novel approach to RAS-targeted cancer therapy.
  • ZnAPC shows potential as a photosensitizer for molecularly targeted photodynamic therapy against cancers driven by NRAS.

More Related Videos

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers08:28

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers

Published on: September 19, 2017

8.7K
Author Spotlight: Characterizing DNA G-Quadruplex by Bis-3-Chloropiperidine Based Chemical Mapping05:32

Author Spotlight: Characterizing DNA G-Quadruplex by Bis-3-Chloropiperidine Based Chemical Mapping

Published on: May 12, 2023

1.8K

Related Concept Videos

Decreasing Function01:27

Decreasing Function

A decreasing function describes a relationship where the output consistently declines as the input increases. This means that for any two input values, if one is greater than the other, the corresponding output is smaller. Mathematically, a function f is decreasing on an interval I if for every x1 < x2​ in I, f (x1) > f (x2). This type of behavior is visually identified on a graph that slopes downward from left to right.The nature of a function can be analyzed by calculating...
303
Fixing Double-strand Breaks02:04

Fixing Double-strand Breaks

The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
14.8K
Fixing Double-strand Breaks02:04

Fixing Double-strand Breaks

4.4K
Decreased Body Temperature01:29

Decreased Body Temperature

A decreased body temperature can occur in patients with hypothermia and frostbite. Heat loss with extended cold exposure overpowers the body's ability to create heat, resulting in hypothermia. Core temperature readings help classify hypothermia. Mild hypothermia is temperatures between 32 °C (89.6 °F) and 35°C (95 °F) and is caused by impaired thermoregulation. Moderate hypothermia is temperatures between 28 C (82.4 °F) and 32 °C (89.6 °F) caused by...
1.1K
Decreased pulse rate01:14

Decreased pulse rate

Bradycardia is a medical condition in which the heart rate is slower than normal. It occurs when the heart's natural pacemaker, the sinus node, generates slower electrical impulses than the standard rhythm. In adults, bradycardia is diagnosed when the pulse rate falls below 60 beats per minute, indicating a deviation from the normal heart rate range.
There are specific risk factors that can elevate the likelihood of developing bradycardia. Advanced age is a significant factor, with...
910
RNA Stability01:53

RNA Stability

Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
35.8K