RNA EDITING IN Calotropis procera MITOCHONDRIAL NADH-DEHYDROGENASE SUBUNIT 3 GENE

Nad3 (NADH-dehydrogenase subunit 3) gene from genomic (accession no. KP171516) and cDNA (accession no. KP171517) was identified in desert plant Calotropis procera using RNA seq and DNA seq data. A number of cytosines are altered to be recognized as uridines in transcripts of the nad3 locus in mitochondria. The nucleotide modifications were found at 11 different nucleotide positions (nucleotide no. 44, 62, 80, 209, 215,230, 247, 266, 275, 317 and 349) within the nad3 coding region. Heterogeneous RNA editing in C. procera nad3 RNA was not detected in this study. These alterations in the mRNA sequence change codon identities to specify 11 amino acids. The alteration in nucleotides leads to codons alteration specifying different amino acids, the common being proline to leuciene (P-L). Other changes were serine to leucine (S-L), serine to phenylalanine (S-F), proline to serine and arginine to tryptophan (R-W). These alterations are common in mitochondrial nad3 gene of most plant species with few differences according to the properties of the amino acids involved.