Poster: Reproductive Development

Abs # 470: Genomic organization of the S core region and the S flanking regions of a class-II S haplotype in Brassica rapa.

Presenter:	Fukai, Eigo , puna@bios.tohoku.ac.jp
Authors	Fukai, Eigo  (A)   Fujimoto, Ryo  (A)   Nishio, Takeshi  (A)
Affiliations:	(A): Graduate School of Agricultural Science, Tohoku University

The genomic organization of S locus of a class-II S haplotype in Brassica rapa was investigated. The 86.4 kb region containing SP11, SRK, and SLG of B. rapa S-60 of class-II S haplotype was sequenced. In the 86.4 kb region, 13 possible genes were found besides SP11-60, SRK-60, and SLG-60. They were 5 sequences isolated as cDNAs, 5 homologues of known genes, cDNAs, or ORFs, and 3 hypothetical ORFs. Based on the nucleotide sequence, however, some of them are thought to be non-functional. Two colinear regions between class-II S-60 and Brassica class-I S haplotypes were identified, i.e., S flanking region 1 sharing partial colinearity of non-genic sequences and S flanking region 2 having high level of colinearity. The observed colinearity made it possible to compare the gene order of SP-11, SRK, and SLG in the S locus between the 5 S haplotypes. It was revealed that the order of SRK and SLG in class-II S-60 is the reverse of those of 4 class-I S haplotypes reported so far. The possible gene designated as SAN1 (S locus Anther-expressed Non-coding RNA like-1), which is located in the intervening region between SP11-60 and SRK-60, had non-coding RNA (ncRNAs) features.