Comparison of three DNA fluorochromes for flow cytometric estimation of nuclear DNA content in plants
Article first published online: 28 APR 2006
Volume 85, Issue 4, pages 625–631, August 1992
How to Cite
Doležel, J., Sgorbati, S. and Lucretti, S. (1992), Comparison of three DNA fluorochromes for flow cytometric estimation of nuclear DNA content in plants. Physiologia Plantarum, 85: 625–631. doi: 10.1111/j.1399-3054.1992.tb04764.x
- Issue published online: 28 APR 2006
- Article first published online: 28 APR 2006
- Received 3 February, 1992; revised 10 April, 1992.
- DNA base content;
- flow cytometry;
- nuclear DNA content;
- propidium iodide
Flow cytometric estimation of nuclear DNA content was performed in six plant species employing three fluorochromes showing different DNA base preferences: propidium iodide (no base preference), 4′,6-diamidino-2-phenylindole (DAPI; AT preference), and mithramycin (GC preference). Nuclei isolated from human leukocytes were used as a primary reference standard. While nuclear DNA contents estimated using propidium iodide were in agreement with published data obtained using other techniques, the values obtained using fluorochromes showing base preference were significantly different. It was found that the differences were caused by the differences in overall AT/GC ratios, and by the species-specific differences in binding of these fluorochromes to DNA. It was concluded that nuclear DNA content estimations performed with fluorochromes showing base preference should be interpreted with caution even when AT/GC ratios of the reference and the sample are equal. The use of intercalting dyes (e.g. propidium iodide) is recommended for this purpose. On the other hand, comparison of the staining behaviour of intercalating dyes with that of dyes showing base preference may give additional information on chromatin structural differences and arrangement of molecule pairs in DNA.