Poster: Late and Moved Abstracts

Abs # 1380: Comparison of genome structure of class…ź self-incompatibility(S ) locus between Brassica oleraceaand Brassica rapa

Presenter:	Ryo, Fujimoto , leo@bios.tohoku.ac.jp
Authors	Ryo, Fujimoto  (A)   Yutaka, Sato  (A)   Makoto, Kusaba  (B)   Takeshi, Nishio  (A)
Affiliations:	(A): Tohoku university (B): Institute of Radiation Breeding,NIAR,MAFF

The determinants of recognition specificity of self-incompatibility in Brassica are SRK(S receptor kinase) in the stigma and SP11/SCR(S locus protein 11/S locus cysteine rich) in the pollen. The pair of S haplotypes, B. rapa S-46 and B. oleracea S-7 , and B. rapa S-47 and B. oleracea S-12 , having highly similar SRK alleles and SP11 alleles showed commonality of self-recognition specificity of S haplotypes. Genome structure of self-incompatibility (S ) locus region was investigated by cloning and sequencing the genomic clones of SRK , SP11 and their of flanking regions. Determined sequences of the S -locus region of B. rapa S-46 , S-47 and B. oleracea S-7 were 20kb,54kb and 32kb including SRK and SP11, respectively. In B. oleracea S-12 , a contig covering SRK and SP11 was not obtained, and therefore 37kb,17kb and 29kb clones including SRK , SP11 , and SLG (S locus glycoprotein), respecitively, were sequenced. A region between SRK and SP11 in B.oleracea was longer than that of B. rapa. Retrotransposon-like sequences were found in the S -locus region of B.oleracea S-7 and S-12 , designated as STF (S locus retrotransposon families ). These results suggest that the S-locus region of B. oleracea was longer than that of B. rapa , and the reason for the difference of the length of the S locus is considered to be due to insertion of retrotransposons at or after the divergence of species .