Isolation of mitochondrial DNA from root tissues of mung bean (Vigna radiata) is quite tedious, complex, and often results in low yield. Hence here we show a simple, rapid, and improved protocol for isolation of mitochondrial DNA from root tissues of hydroponically grown mung bean plants. This method involves purification of mitochondria and subsequent isolation of DNA from obtained purified mitochondria. For this purpose, mitochondria were isolated using a discontinuous Percoll gradient centrifugation followed by RNase I treatment to the isolated DNA to remove any traces of RNA contamination. The mitochondrial DNA was isolated from mitochondrial samples by commonly used CTAB method. The specificity of isolated mitochondrial DNA was confirmed using mtDNA-specific genes (NAD1 and COX3). β-Actin primer was used to check the nuclear DNA contamination. PCR amplification was observed in mtDNA specific genes NAD1 and COX3 except nuclear encoded β-actin gene suggesting that mitochondrial DNA was not contaminated by nuclear DNA.
Keywords: DNA; Mitochondria; Mung bean; Percoll gradient; β-Actin.