AN OPTIMIZED COMET ASSAY PROTOCOL FOR DROSOPHILA MELANOGASTER

Yıl 2019, Cilt: 2 Sayı: 1, 73 - 76, 31.07.2019

Fahriye Zemheri Navruz

Öz

Genotoxins can cause various disorders in chromosome and DNA structure
such as gene mutations, chromosome abnormalities and DNA chain breaks.  This situation has been associated with the
concept of genetic toxicity. 
Genotoxicity tests have been developed to predict the possible effects
of genotoxins on all living things in nature. 
The single cell gel electrophoresis assay (SCGE, also known as comet
assay) is used as the fastest, easy and sensitive. The Comet method is based on
distinctive migration characteristics of DNA molecules having different
electrical charges and molecular weights at alkaline pH. According to this
method, nucleolus’ and cells can be visualized by staining with a fluorescent
dye by first placing between the agarose layers and then running at alkaline
electrophoresis buffer and lysis solution and lastly applying neutralization
procedure. The displayed DNA fractures are measured and evaluated according to
tail length. DNA images are graded according to the degree of damage. DNAs that
are not damaged are evaluated as arbitrary units (AU) by scoring 0 and damage
DNAs are scored from 1 to 4 according to the degree of damage. Comet assay is a
useful method in evaluating the potential toxic effect.  Drosophila melanogaster is the most
important non-mammalian organism used in the fields of medicine and biology. Drosophila melanogaster has been used
for many years as an in vivo model organism for potential toxicity and
genotoxicity studies. It is important to determine the damage of genotoxins on
DNA. It was preferred because it was easy to obtain and grow in the laboratory,
the larvae were cheap and the life cycle was short-lived. Comet analysis using Drosophila
melanogaster tissues to determine the damage of various genotoxins on DNA
is an effective and easy method. This study aims to explain the alkaline Comet
assay aimed to determine the effect of general various genotoxins on Drosophila melanogaster tissues. 

Anahtar Kelimeler

Drosophila Melanogaster, Genotoxicity, Comet assay

Kaynakça

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