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. 1991 Mar 1;88(5):1602–1605. doi: 10.1073/pnas.88.5.1602

Gene silencing in a polyploid homosporous fern: paleopolyploidy revisited.

G J Gastony 1
PMCID: PMC51072  PMID: 11607154

Abstract

Because of their high chromosome numbers, homosporous vascular plants were considered paleopolyploids until recent enzyme electrophoretic studies rejected this hypothesis by showing that they express only diploid numbers of isozymes. In polyploid sporophytes of the homosporous fern pelleae rufa, however, progressive diminution of phosphoglucoisomerase activities encoded by one ancestral genome culminates in tetraploid plants exhibiting a completely diploidized electrophoretic phenotype for this enzyme. The demonstration that such gene silencing can make a polyploid fern look isozymically like a diploid questions the validity of isozyme evidence for testing the paleopolyploid hypothesis and supports the proposed role of polyploidization followed by genetic diploidizaton in the evolutionary history of homosporous pteridohytes.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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