Related Experiment Video
Updated: Jul 7, 2026
07:10
Split Hybridization Probe Utilizing a DNA Fluorescent Light-up Aptamer as a Signal Reporter for Sequence-Specific Nucleic Acid Analysis
Published on: July 8, 2025
Detection of hybridized probe.
1Harvard Medical School and Dana-Farber Cancer Institute, Boston, Massachusetts, USA.
Current Protocols in Molecular Biology
|February 12, 2008
Summary
Autoradiography detects radioactive probes in cells using film or emulsion methods. Film is suitable for tissues, while emulsion offers single-cell resolution for detailed biological studies.
Area of Science:
- Molecular Biology
- Cell Biology
- Biotechnology
Background:
- Autoradiography is a technique for visualizing and quantifying the distribution of radioactive isotopes within biological samples.
- It relies on the detection of emitted radiation by a photographic emulsion or film.
- This method is crucial for mapping the location of specific molecules, such as nucleic acids or proteins, that have been labeled with radioisotopes.
Purpose of the Study:
- To describe the methodologies of autoradiography for detecting and quantifying radioactive probes in cytological preparations.
- To differentiate between the applications and requirements of film and emulsion autoradiography.
- To provide a guide for researchers utilizing these autoradiographic techniques.
Main Methods:
- Film autoradiography: Utilizes photographic film to detect signals from radioactive probes (e.g., phosphorus-32, sulfur-35) hybridized to large organs or tissues.
- Emulsion autoradiography: Employs photographic emulsion for high-resolution detection, enabling analysis at the single-cell level.
- Both methods involve the hybridization of a labeled probe to target molecules within cytological preparations, followed by exposure to a detection medium.
Main Results:
- Film autoradiography is effective for detecting radioactive signals in macroscopic samples like large tissues or organs.
- Emulsion autoradiography provides the necessary resolution to localize signals within individual cells, crucial for detailed cellular and subcellular analysis.
- The choice between film and emulsion depends on the experimental scale and the required level of spatial resolution.
Conclusions:
- Autoradiography, using either film or emulsion, is a versatile technique for molecular localization in biological samples.
- Film autoradiography is practical for broad tissue analysis, whereas emulsion autoradiography is essential for high-resolution cellular studies.
- Understanding the distinct applications of each method allows for optimized experimental design in molecular biology and cell biology research.
Related Concept Videos
02:57Southern Blot
Agarose gel electrophoresis is very useful in separating DNA fragments by size. Running a DNA ladder containing fragments of the known length alongside the sample helps determine the approximate length of the sample DNA fragments. However, additional steps are needed to verify the sequence identity of the sample DNA fragments.
Denatured DNA fragments must be transferred onto a carrier membrane from the gel to make it accessible to a probe - a small ssDNA fragment complementary to the target DNA...
Denatured DNA fragments must be transferred onto a carrier membrane from the gel to make it accessible to a probe - a small ssDNA fragment complementary to the target DNA...
03:31Labeling DNA Probes
DNA probes are fragments of DNA labeled with a reporter tag to enable their detection or purification. The resulting labeled DNA probes can then hybridize to target nucleic acid sequences through complementary base-pairing, and may be used to recover or identify these regions.
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...
02:07FISH - Fluorescent In-situ Hybridization
Fluorescence in situ hybridization, or FISH, was developed in the early 1980s and has quickly become one of the most widely used techniques in cytogenetics. Labeled probes are used to bind complementary DNA or RNA sequences on a chromosome or in a region within a cell. Earlier, the probes could only be obtained by cloning or reverse transcription of a DNA template. Currently, the probe oligonucleotides can be synthesized synthetically. Additionally, with the advancement of optical techniques,...
02:31In-situ Hybridization
In situ hybridization (ISH) is a technique used to detect and localize specific DNA or RNA molecules in cells, tissue, or tissue sections using a labeled probe. The technique was first used in 1969 for the investigation of nucleic acids. It is currently an essential tool in scientific research and clinical settings, especially for diagnostic purposes.
Types of probes and labels
A probe is a complementary strand of DNA or RNA that binds to corresponding nucleotide sequences in a cell. Many...
Types of probes and labels
A probe is a complementary strand of DNA or RNA that binds to corresponding nucleotide sequences in a cell. Many...
02:34DNA Microarrays
Microarrays are high-throughput and relatively inexpensive assays that can be automated to analyze large quantities of data at a time. They are used in genome-wide studies to compare gene or protein expression under two varied conditions, such as healthy and diseased states. Microarrays consist of glass or silica slides on which probe molecules are covalently attached through surface functionalization. Most commonly, the slides are prepared through the chemisorption of silanes to silica...