Quantization of chloroplast DNA using dot blot filter hybridization with double-stranded probes.

Hybridization characteristics of purified chloroplast DNA, immobilized in 'dot blots' on nitrocellulose filters using radiolabeled chloroplast DNA restriction fragments or recombinant DNA probes were investigated. Conditions are described which proved a near linear relationship between amounts of hybridization and amounts of immobilized DNA. A standard curve constructed using such data provided a simple means for quantizing specific chloroplast DNA sequences in partially purified total DNA from protoplast extracts. Using this technique, DNA sequences corresponding to about 0.01% of the total immobilized DNA could be detected.