ISSN:
1432-2242
Keywords:
Sulfurea
;
Tomato
;
Paramutation
;
Dominant position effect variegation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract A new allele, SC148, of thesulfurea locus inLycopersicon esculentum was detected in a line derived after repeated selfing of plants that had been regenerated from tissue culture. Like the originalsulf mutant, SC148 displayed two mutant phenotypes: green-yellow speckled plants in which thesulf vag allele is present and pure yellow plants homozygous for thesulf tpura allele. Although the mutant alleles are recessive to wild-type, an unpredictable number of variegated and pura plants appeared in F1 progenies that had been derived from crosses between SC148 and wild-type tomato plants. The presence of the wild-typesulf + allele in these variegated heterozygotes was demonstrated using a cytological marker that is linked tosulf. It is concluded that the mutantsulf allele of SC148, imposes its variegated expression state on the wild-typesulf + allele present insulf +/sulfvag heterozygotes. This behaviour, known as paramutation, has also been described for the originalsulf allele. The SC148 allele, however, seems to induce changes at an earlier stage in development. The analogy of this paramutagenic system to dominant position effect variegation inDrosophila is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01184914
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