Nuclear inheritance of polyphenol oxidase in Nicotiana [Tobacco]

Isozymes of polyphenol oxidase (EC 1.10.3.1) from several species of tobacco and hybrids derived from them were resolved by polyacrylamide gel electrophoresis. The isozymes, detected by DOPA oxidase activity, have a range of molecular weights similar to that reported for many other species. All species examined exhibited isozymes of Mr 48 kD. However, analysis of isozymes of other molecular weights in interspecific hybrids revealed that PPO isozymes present in the paternal parent, but absent from the maternal parent, were present in hybrids in each case studied. These results indicate a nuclear inheritance of PPO isozymes in Nicotiana.