Coevolution of the S-locus genes SRK, SLG and SP11/SCR in Brassica oleracea and B. rapa

Keiichi Sato, Takeshi Nishio, Ryo Kimura, Makoto Kusaba, Tohru Suzuki, Katsunori Hatakeyama, David J. Ockendon, Yoko Satta

Research output: Contribution to journalArticlepeer-review

113 Citations (Scopus)

Abstract

Brassica self-incompatibility (SI) is controlled by SLG and SRK expressed in the stigma and by SP11/SCR expressed in the anther. We determined the sequences of the S domains of 36 SRK alleles, 13 SLG alleles, and 14 SP11 alleles from Brassica oleracea and B. rapa. We found three S haplotypes lacking SLG genes in B. rapa, confirming that SLG is not essential for the SI recognition system. Together with reported sequences, the nucleotide diversities per synonymous and nonsynonymous site (π s and π N) at the SRK, SLG, and SP11 loci within B. oleracea were computed. The ratios of π NS for SP11 and the hypervariable region of SRK were significantly >1, suggesting operation of diversifying selection to maintain the diversity of these regions. In the phylogenetic trees of 12 SP11 sequences and their linked SRK alleles, the tree topology was not significantly different between SP11 and SRK, suggesting a tight linkage of male and female SI determinants during the evolutionary course of these haplotypes. Genetic exchanges between SLG and SRK seem to be frequent; three such recent exchanges were detected. The evolution of S haplotypes and the effect of gene conversion on self-incompatibility are discussed.

Original languageEnglish
Pages (from-to)931-940
Number of pages10
JournalGenetics
Volume162
Issue number2
Publication statusPublished - 2002 Oct 1

ASJC Scopus subject areas

  • Genetics

Fingerprint Dive into the research topics of 'Coevolution of the S-locus genes SRK, SLG and SP11/SCR in Brassica oleracea and B. rapa'. Together they form a unique fingerprint.

Cite this