The S11 and S13 self incompatibility alleles in Solanum chacoense Bitt. are remarkably similar

Plant Mol Biol. 1994 Feb;24(4):571-83. doi: 10.1007/BF00023555.


A genomic clone of the S11 allele from the self-incompatibility locus (S locus) in Solanum chacoense Bitt. has been isolated by cross-hybridization to the S. chacoense S13 allele and sequenced. The sequence of the S11 allele contains all the features expected for S genes of the Solanaceae, and S11 expression, as assessed by northern blots and RNA-PCR, was similar to that of other S. chacoense S alleles. The S11 protein sequence shares 95% identity with the phenotypically distinct S13 protein of S. chacoense and is the gametophytic S allele with the highest similarity to an existing allele so far discovered. Only 10 amino acid changes differentiate the mature proteins from these two alleles, which sets a new lower limit to the number of changes that can produce an altered S allele specificity. The amino acid substitutions are not clustered, suggesting that an accumulation of random point mutations can generate S allele diversity. The S11 intron is unusual in that it could be translated in frame with the coding sequence, thus suggesting an additional mechanism for the generation of new S alleles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles*
  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Southern
  • Cloning, Molecular
  • Crosses, Genetic
  • DNA, Complementary
  • Genes, Plant / genetics*
  • Genomic Library
  • Introns / genetics
  • Molecular Sequence Data
  • Plant Proteins / chemistry
  • Plant Proteins / genetics*
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Solanum tuberosum / genetics*


  • DNA, Complementary
  • Plant Proteins
  • S11 protein, Solanum chacoense
  • S13 protein, Solanum chacoense

Associated data

  • GENBANK/S69589