The membrane domain of complex I is not assembled in the stopper mutant E35 of Neurospora

The assembly of mitochondrial NADH : ubiquinone oxidoreductase (complex I) was studied in the E35 stopper mutant of Neurospora crassa at different times during growth in liquid media. Assembly of complex I as well as of its membrane domain is impaired in this strain throughout the growth period. Nevertheless, a structure that resembles the peripheral arm of the enzyme is still formed in the mitochondria of this mutant. The absence of the membrane domain of complex I in E35 can be attributed to the specific deletion of the mitochondrial ND2 and ND3 subunits of the enzyme.Key words: mitochondria, complex I, stopper mutants, Neurospora crassa.