Mk. Zubko et A. Day, STABLE ALBINISM INDUCED WITHOUT MUTAGENESIS - A MODEL FOR RIBOSOME-FREE PLASTID INHERITANCE, Plant journal, 15(2), 1998, pp. 265-271
Maternally inherited chlorophyll deficiency, or albinism, is a standar
d marker in plant cytoplasmic genetics. Its stability is consistent wi
th mutations in the plastid genome. Nuclear mutations inducing plastid
ribosome deficiency (PRD) also lead to maternally inherited chlorophy
ll deficiency. Here we report that stable chlorophyll deficiency can b
e efficiently generated in cruciferous plants without mutagenesis by a
short exposure to spectinomycin, an inhibitor of plastid protein synt
hesis. We show that the chlorophyll-deficient phenotype results from a
deficiency in plastid ribosomes and plastid translation products. Los
s of plastid ribosomes is irreversible. The data suggest that mutation
s are not essential for generating inheritable PRD. It allows the form
ulation of a more general model in which stable PRD can be induced by
a variety of factors that prevent the formation of functional plastid
ribosomes. A non-mutational mechanism for generating inheritable chlor
ophyll deficiency has implications for the origin and inheritance of g
reen-white variegation in nature.