EFFECTS OF IRON-DEFICIENCY ON IRON SUPEROXIDE-DISMUTASE EXPRESSION INNICOTIANA-TABACUM

Some dicotyledonous species, including Nicotiana tabacum, have four is ozymic forms of superoxide dismutase (SOD, EC 1.15.1.1) one of which, FeSOD, contains iron at its active site. Here we analyze the effects o f iron deficiency on the expression of the nuclear gene sodB that enco des FeSOD. We show that in iron-deficient plants the level of active e nzyme as well as the apoprotein is reduced. This decrease is a result of a lower sodB transcript level. iron-regulated transcriptional and p ost-transcriptional control of sodB is discussed.