Dna Unwinding Measurement

DNA unwinding measurement refers to methods that quantify how double-stranded DNA separates or changes its helical structure, a key feature of replication, repair, recombination, and transcription. These approaches monitor the conversion of duplex DNA into single strands as helicases, chemical conditions, temperature, or applied mechanical force disrupt base-pairing and alter DNA extension, fluorescence, or other measurable signals. In biology, such measurements reveal helicase activity, strand-separation rates, energy requirements, and the effects of sequence or DNA-binding proteins. The resulting data help characterize genome-maintenance mechanisms and evaluate molecular factors that influence DNA stability and accessibility.

Dna Unwinding Measurement - Related Videos

Research

JoVE Journal - Biochemistry
Free Sample

Single-Molecule Real-Time Visualization of DNA Unwinding by CMG Helicase

0 Views •

Cited by 1 •

2024

This protocol demonstrates performing a single-molecule assay for live visualization of DNA unwinding by CMG helicase. It describes (1) preparing a DNA substrate, (2) purifying fluorescently labeled Drosophila melanogaster CMG helicase, (3) preparing a microfluidic flow cell for total internal reflection fluorescence (TIRF) microscopy, and (4) the single-molecule DNA unwinding assay.

Education

JoVE Core - Molecular Biology

DNA Topoisomerases

0 Views •

2020

Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA. Types and Mechanism of action Topoisomerases are divided into two main types. Type I...

DNA Helicases

0 Views •

2020

DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...

In Vivo Alkaline Comet Assay and Enzyme-modified Alkaline Comet Assay for Measuring DNA Strand Breaks and Oxidative DNA Damage in Rat Liver

0 Views •

Cited by 17 •

2016

The alkaline comet assay measures DNA strand breaks in eukaryotic cells. By adding an Endonuclease III or human 8-oxoguanine-DNA-N-glycosylase digestion step, the assay can efficiently detect oxidative DNA damage. We describe methods for using these assays to detect DNA damage in rat liver.

DNA Replication

0 Views •

2020

DNA replication involves the separation of the two strands of the double helix, with each strand serving as a template from which the new complementary strand is copied. After replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand. This is known as semiconservative replication. The resulting DNA molecules have the same sequence and are divided equally into the two daughter cells. Replication in Prokaryotes DNA replication uses a large number of...

View All Results

FAQs

Related Topics