[8]. Research using forward and
reverse genetics approaches has revealed that nuclear-encoded
pentatricopeptide repeat (PPR) proteins play important roles in
RNA editing in plastids and mitochondria. The PPR proteins are
characterized by a tandem array of a degenerate 35-amino-acid
repeat. There is a very large family of genes encoding these
proteins in land plants. This gene family has 450 members in
Arabidopsis and 477 members in rice