DNA Fragmentation / DNA Fragmentation in sperm

 

DNA Fragmentation

DNA FRAGMENTATION

Fragmentation:-

DNA fragmentation is the splitting or breaking of DNA strands into pieces. It can be done intentionally by lab workers or by cells, or it can happen automatically. Spontaneous or accidental DNA fragmentation is a gradual complication of cells.
DNA sequencing is often required before library building or sequential DNA sequencing. Various methods have been used that involve mechanical fragmentation of DNA where DNA is divided by laboratory staff. Such methods include sonication, needle shear, nebulization, point-sink shearing and passage through the cell. [7]
Prohibition mutations are a deliberate breakdown of DNA strands. It is an enzyme-based drug used in biotechnology to cut DNA into smaller pieces to study the breakdown of fossil lengths between humans or genetic makeup. [8] This process separates DNA by simultaneous splitting of two strands, or by making nicks in each strand of dsDNA to produce dsDNA breaks. [9]
The acoustic shear for the transmission of high energy waves is transmitted to the DNA library. A transducer is a circle formed in such a way that the waves meet where they are intended. [9]
Nebulization forces the DNA into a small hole in the wing of the nebulizer, leading to the formation of fine fog that accumulates. Residual size is determined by the pressure of the gas used to push the DNA through the nebulizer, the speed at which the DNA solution passes through the hole, the viscosity of the solution, and the temperature. [9] [10]
Sonication, a type of hydrodynamic shear, incorporates DNA into acoustic cavitation and hydrodynamic shearing by being exposed to short sonication moments, which often lead to 700bp fragments. In DNA fragmentation, sonication is commonly used in an explosive cycle using a probe-type sonicator. [11]
Point-sink shearing, a type of hydrodynamic shear, uses a syringe pump to construct hydrodynamic shear forces by compressing the DNA library with a small spontaneous contraction. About 90% of the residual length falls into the double range. [9]
Shaving the needle creates the ability to shave by transferring DNA libraries with a small measuring needle. [9] DNA passes through a measuring needle several times to physically break the DNA into fine pieces.
French pressure cells transfer DNA through a small valve under high pressure to create high shear strength. [9] With a French machine, the shear force can be carefully adjusted by adjusting the piston pressure. The media provides a single pass in the area of ​​high shaving power, reducing damage to fragile structures due to repeated cutting, as is the case with other disturbances.

SOURSE OF FRAGMENTATION:-

It is found in many sources. There are many factors that contribute to the migration of DNA strands by gel, including:

1.

The size of the DNA strands. The flow of the gel is very different from the size of the log10 in the pair of DNA fragment line. Larger pieces are delayed while smaller pieces move much faster.

2.

Agarose Torture. This is a critical determinant of the effective rate of fragmentation of DNA fragments. With 0.5% agarose gel, this range can be 1 kilobase (kb) -20 kb; with 1% gel, the diameter is 0.5 kb-10 kb. DNA fragments outside the active range will not be properly solved.

3.

Electrophoresis Reminder. Although DNA fragments move about 10% faster on used TAE gels than TBE gels, the difference in resolution is not significant. Note that the volume of the TAE is low, so the buffer needs to be replaced or repeated during extended electrophoresis operation. This step is not required if you are using TBE.

4.

Electrical power used. In the field of low energy (<5 V / cm), the migration of a DNA fragment is equal to the energy used. Electrophoresis with high field strength (> 5 V / cm) leads to rapid migration in proportion to high cell types and loss of solution. Normally, with high resolution, electrophoresis is performed at 1 V / cm.

Fragmentation

5.

Dye containing ethidium bromide causes a slight decrease in DNA sequence but no significant loss of resolution. The use of this color in the gel facilitates the detection and consideration of samples and levels after electrophoresis from ethidium bromide fluoresces when exposed to UV light.

Gels are thrown on a straight plate closed at the sides and ended with tape. To make springs, a template or camp is placed by standing next to one end of the plate 1 mm above the glass plate (Figure 1A). Agarose in the right place is poured into an electrophoresis buffer (bottle or bottle) and cooled to -60 ° C. Ethidium bromide can be added to the final filter of 0.5-1.0 μg / ml. The solution is mixed and poured into jelly plates, air bubbles are avoided, and allowed to harden. After combing and assembling the seal, the gel is applied to the electrophoresis unit; including enough electrophoresis buffer for gel application. Samples and standards are uploaded to sources (Fig. 1B) using a micropipetter. Multiple loading buffers are widely used, (1) to ensure complete sample loading at the source by increasing the sample volume and (2) by providing the dye passing through the gels at known prices. Six concentrates of these buffers are usually made with 0.25% bromophenol blue (BPB) mixed with a DNA fragment of about 300 bp, 0.25% xylene cyanol FF migrates as a 4-kb DNA fragment, and - designed to increase sample size.