Study On Rice MtALDH In Transgenic Tobacco

Aldehyde dehydrogenases(ALDH) are enzymes that depend on many aldehydes.Different types of ALDH have been distinguished based on their physicochemical andenzymological properties, subcellular localization and tissue distribution. It becomesincreasingly evident that some ALDH proteins have other important physiologicalfunctions in addition to their catalytic properties in recent reserch.At present, ALDHs have been identified and characherized in human beings. Theirmain fuctions are involved in the ethanolic metabolism and in the detoxication ofaldehyde in liver. In recent years, study on the ALDHs physiological functions hasbecome a hot spot since the restorer of fertility 2 gene(rf2) of CMS-T maize was clonedby Cui in 1996. And the rf2 gene was demonstrated as a mitochondrial aldehydedehydrogenase (mtALDH). Studies on the mtALDHs of rice, tobacoo and maize werereviewed and the important physiological functions of the three plants were discussedin this article. The author points out that mtALDHs were involved in the ethanolicmetabolism. Some mtALDHs are expressed specially in the reproductive organs, whichindicates that the mtALDHs may relate to the development of pollens.Molecular mechanisms of cytoplasmic male sterility and its relationship withmtALDH were reviewed. The author points out that it is not very clear about themtALDHs with the restoring of fertility, and further researches should go on.