Abstract
This study is an example of using 5-ethynyl-2′-deoxyuridine (EdU) for detecting sister chromatid exchanges (SCEs) at chromosomal level. Here we report a detailed protocol for differential labeling sister chromatids in barley (Hordeum vulgare, 2n = 14) cells that is based on the incorporation and simple detection of EdU. The perfect distinguishing of sister chromatids enabled an analysis of the effects of two model agents—maleic acid hydrazide (MH) and gamma rays—on the formation of SCEs. Using this method, we demonstrated the high sensitivity of barley cells to maleic hydrazide, which is expressed as an increased level of SCEs. A gamma ray induced only slightly more SCEs than in the control cells. The possible mechanisms of MH and gamma ray action in respect to distinguishing chromatids using EdU are discussed. Recommendation for SCEs visualization using EdU as an easy and quick method that can be successfully adapted to other plant species and potentially for human genotoxicity studies is presented.
Highlights
The consequences of the influence of environmental factors are detected using cytogenetic and molecular biological markers
Chromatids can be distinguished within one chromosome, and the sister chromatid exchanges (SCEs) are seen with great clarity and resolution
Due to the similarity of the fourteen barley chromosomes, the level of SCEs was estimated by analyzing the following parameters: the frequency, which is characterized by the number of SCEs per diploid cell, the maximum number of SCEs per chromosome, and the frequency of chromosomes with no SCEs (Table 1, Figure 2)
Summary
The consequences of the influence of environmental factors are detected using cytogenetic and molecular biological markers. After BrdU is incorporated, the differential staining of SCEs can subsequently be achieved by using different methods: modified Giemsa staining (Korenberg and Freedlender, 1974), 33258 Hoechst (Perry and Wolff, 1974), acridine orange or 4′-6′-diamidino-2-phenylindole (DAPI) (Lin and Alfi, 1976). These approaches, which are based on BrdU as a label, together with the simplicity and low SCE Using EdU number of cells that need to be scored have made SCEs the preferred end point in mutagenesis studies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
