Breakdown of self-incompatibility in tetraploid Lycopersicon peruvianum: inheritance and expression of S-related proteins

• Published in: Theoretical and applied genetics 1997-10, Vol.95 (5/6), p.992-996
• Main Authors: Chawla, B, Bernatzky, R, Liang, W, Marcotrigiano, M
• Format: Article
• Language: English
• Subjects: alleles; allelic dosage; Biological and medical sciences; Classical genetics, quantitative genetics, hybrids; Fundamental and applied biological sciences. Psychology; gene dosage; Genetics of eukaryotes. Biological and molecular evolution; glycoproteins; growth; heterogenic pollen; homogenic pollen; inheritance (genetics); leaves; loci; Lycopersicon peruvianum; plant proteins; pollen; pollen tubes; protein composition; Proteins; Pteridophyta, spermatophyta; regenerative ability; ribonucleases; segregation; self compatibility; self incompatibility; self-pollination; Solanum peruvianum; styles; tetraploidy; tissue culture; Vegetals
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s001220050652

Lycopersicon peruvianum displays gametophytic self-incompatibility (GSI). We have isolated self-compatible (SC) tetraploids of L. peruvianum from tissue-cultured leaves and have explored the expression and inheritance of their S-related proteins. The S-related protein profiles of styles of SC tetraploids were indistinguishable from the diploid self-incompatible (SI) explant source based on SDS-PAGE. All progeny obtained from self-fertilization of two tetraploids were SC. Cloned cDNA sequences of the S-related proteins were used to determine the inheritance of this locus in these progeny through Southern hybridization. The allelic ratio, as determined from the intensity of DNA restriction fragments, was consistent with the predicted ratio if only pollen bearing two different alleles was successful in achieving fertilization. All progeny obtained had at least one copy of each allele, and individuals fully homozygous for either allele were not found, indicating that pollen grains bearing two identical alleles were inhibited. In addition, the level of expression of the S-related proteins in the progeny correlated with the allelic dosage at the DNA level. We demonstrate that the observed self-compatibility in the tetraploids was not caused by an alteration in the expression of S-related proteins.