Question

GMO Foods Assignment. Answer the question below in paragraphs format.

What is DNA isolation?

What is PCR

what is CaMV promoter?

What is cyf1 gene?

What is and plant chloroplast and positive control?

Answer 1

A) DNA Isolation:

DNA isolation can be described as a process of obtaining/extracting purified DNA from various sources. Source can be bacteria, blood, tissue, hair, semen etc.

There are various methods of DNA isolation depending on the type of source.

If you have tissue as a source, you can homogenise it; either chemically or mechanically. Rupturing of cell wall can be done by lysozyme (in case of bacteria) and zymolase in case of yeast or fungi. Cell membrane can then be ruptured by using detergents such as SDS or by using proteinases, or chelators such as EDTA or Urea.

BASIC STEPS INVOLVED IN ALL DNA EXTRACTION METHODS ARE AS FOLLOWS:

SOURCE CELL TISSUE CULTUREEXTRACT CELL Lysis PnysicAL/cHEMICAL) WASH CDETERMENTS STEPSSEPARATION BY ADSORPTION) RE MOVAL OF MENBRAN LipiDs PRO TE ASE TREAT MENT RO TEIN DENNTURATION AND REMoVAL wAsh STEPS REMoVAL OF OTHER CELLULAR CONTAMINANTS RNA ase TREATMENT RNA RE NOVAL PURİFIED DNA

B) PCR

POLYMERASE CHAIN REACTION was formulated in 1985 by KERRY MULLIS. It is used to obtain selective amplification of a specific target DNA sequence within a collection of DNA sequence. To do so, some prior DNA sequence information from the target sequence is required. This information can then be used to design two primers(oligonucleotide) which are specific to the target sequence ans usually 15-25 nucleotides long.

Primers are then added to denatured template DNA and then they bind specifically to complementary DNA sequences at the target site. Suitable heat stable DNA polymerases such as Taq polymerase and DNA precursors, the DNA triphosphates dATP, dCTP, dGTP, dTTP are used. The role of primer is to initiate the synthesis of new DNA strands which are complementary to target DNA segment and will overlap each other.

C) Cauliflower mosaic virus promoter is 35S promoter which is widely used in all GM crops,especially GM maize. It is a constitutive promoter.This promoter is not only active in plants but also in the gut of E. coli , in yeast and in extracts of cancer cell lines of humans. This promoter is used to activate artificially inserted foreign genes in transgenic plants. It can also be used for detection of genetically modified organisms by targeting different regions of this promoter.