Self-incompatibility proteins in plants: Detection, genetics, and possible mode of action

Abstract

1. Acrylamide gel electrophoresis and immunodiffusion were used to study the buffer soluble basic proteins of stigmatic homogenates of several S allele genotypes of cabbage. 2. Each S allele genotype had a different electrophoretic protein band pattern. 3. Each of the genotypes S1S1, S2S2, and S3S3 had a unique electrophoretically separated protein band. 4. The unique protein band of genotypes S2 and S2´ was shown to be the S allele specific antigen previously identified by immunodiffusion. 5. The electrophoretically separated S allele specific proteins were shown to be heritable by the presence in heterozygous genotypes of the unique proteins of each of the two homozygous parents. 6. It is hypothesised that S allele specific proteins differ by amino acid substitutions. 7. It is postulated that the basic S proteins act as regulators of enzymes needed for pollen germination and tube growth. © 1970, The Genetical Society of Great Britain. All rights reserved.