PLANT PHYSIOLOGY , Vol 112, Issue 2 651-657, Copyright © 1996 by American Society of Plant Biologists
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BIOCHEMISTRY AND ENZYMOLOGY |
Temporal and Spatial Distribution of Ferredoxin Isoproteins in Tomato Fruit
K. Aoki and K. Wada
Department of Biology, Faculty of Science, Kanazawa University, Kakuma, Kanazawa 920-11, Japan
Five ferredoxin (Fd) isoproteins (FdA, FdB, FdC, FdD, and FdE) were
isolated from tomato (Lycopersicon esculentum cv Momotaro) fruit. These
isoproteins showed differential temporal and spatial accumulation patterns.
FdA and FdC were present in leaves, FdE was present in roots, and FdB and
FdD were fruit-specific. During fruit growth, the relative abundance of FdA
decreased and that of FdE increased. The FdE/FdA ratio was higher in the
inner tissues of the fruit than in the outer tissue, and it was correlated
with starch accumulation. In dark-grown fruit the contents of FdA, FdB, and
FdC, as well as chlorophyll, decreased remarkably relative to their
light-grown counterparts; however, the contents of FdE and starch did not
change significantly. Under in vitro conditions FdE showed higher
cytochrome c reduction activity than FdA and FdB. These results, together
with their N-terminal sequences, indicate that both photosynthetic- and
heterotrophic- type Fd isoproteins are present in tomato fruit.
