Characterization of the flanking regions of the S-RNase genes of Japanese pear (Pyrus serotina) and apple (Malus x domestica).
Genomic sequences of the self-incompatibility genes, the S-RNase genes, from two rosaceous species, Japanese pear and apple, were characterized. Genomic Southern blot and sequencing of a 4.5-kb genomic clone showed that the S4-RNase gene of Japanese pear is surrounded by repetitive sequences as in the case of the S-RNase genes of solanaceous species. The flanking regions of the S2- and Sf-RNase genes of apple were also cloned and sequenced. The 5' flanking regions of the three alleles bore no similarity with those of the solanaceous S-RNase genes, although the position and sequence of the putative TATA box were conserved. The putative promoter regions of the Japanese pear S4- and apple Sf-RNase genes shared a stretch of about 200bp with 80% sequence identity. However, this sequence was not present in the S2-RNase gene of apple, and thus it may reflect a close relationship between the S4- and Sf-RNase genes rather than a cis-element important in regulating gene expression. Despite the uniform pattern of expression of the rosaceous S-RNase genes, sequence motifs conserved in the 5' flanking regions of the three alleles were not found, implying that the cis-element controlling pistil specific gene expression also locates at the intragenic region or upstream of the analyzed promoter region.
Ushijima
K
K
Kihara Institute for Biological Research, Yokohama City University, Maioka 641-12, Totsuka-ku, Yokohama 244, Japan.
Sassa
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H
Hirano
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H
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D005638:Fruit / Q000235:genetics*; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D012260:Ribonucleases / Q000737:chemistry* / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D016385:TATA Box / Q000235:genetics; D014158:Transcription, Genetic / Q000235:genetics
D010940:Plant Proteins; D012260:Ribonucleases; C022542:ribonuclease S; C112616:self-incompatibility ribonuclease S4