THE PLANT CELL, Vol 5, Issue 8 963-971, Copyright © 1993 by American Society of Plant Biologists
Analysis of Leaf Sectors in the NCS6 Mitochondrial Mutant of Maize
J. Gu, D. Miles and K. J. Newton
Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211
The nonchromosomal stripe (NCS6) mutation of maize is a partial deletion of
the mitochondrial cytochrome oxidase subunit 2 (Cox2) gene. The Cox2
deletion and a narrow yellow striping phenotype are inherited together in a
maternal fashion. The striped plants are heteroplasmic for mutant and
normal Cox2 genes. Only the mutant Cox2 gene is detected within the yellow
stripes, whereas both normal and mutant forms of the gene are present in
the green sectors of the NCS6 plants. In the green leaves of nonstriped
relatives, only the normal Cox2 gene is found. Both the structure and
functioning of the chloroplasts in the yellow leaf sectors of NCS6 plants
are altered. The pleiotropic effects of the NCS6 mutation suggest that
mitochondrial function is required for the development of
photosynthetically competent chloroplasts.
