|Budget Amount *help
¥6,300,000 (Direct Cost : ¥6,300,000)
Fiscal Year 1993 : ¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1992 : ¥3,900,000 (Direct Cost : ¥3,900,000)
We have investigated expression of mutant forms (lox1, lox2, lox3) of the genes encoding lipoxygenase 1,2,3 (L1, L2, L3) which form undesirable volatile carbonyl compounds from linoleic acid in the food processing of soybean seeds, and investigated genetic variance and suppression by antisense oligo-nucleotideof barley alpha-amylase which is an important malting character for brewing.
1) Soybean lipoxygenase (investigator T.Takano, G.Takeda) : The lox2 transcripts accumulate normally. The enzymatically inactive lox2 gene product is readily detectable in mid-maturation-stage seeds but is apparently unstable, since it is absent from mature seed. We presented evidence that the missense mutationsubstituting Gln for His-532 results in the loss of L2 from mature seeds. The lox3 exhibits no detectable accumulation of the Lox3 transcript. Two substitutions of the 5'-flanking regions are involved in changing a paired-box of AAATAC.Our results indicate that these two substitutions occur in redundant cis-acting elements, probably in the paired-box, suggesting themolecular basis for the L3 null mutation.
2-1) RFLPs detected with the high-pI alpha-amylasegene in barley (investigator G.Takeda, T.Takano) : Genomic southern blot analysis using cDNA clone as a prove was carried to detect the polymorphisms of the gene in cultivated and wild barley. Type A and Type D are specific to two rowed and six-rowed cultivars, respectively. H.spontaneum, the wild ancestor of H.vulgare, shows only one pattern similarto Type C,but detected fragments have low homology.
2-2) Suppression of alpha-amylase by antisense in barley (investigator N.Tsutsumi) : In cultured aleurone cells, alpha-amylase activity are efficiently decreased by addition of antisenseoligodeoxynucleotide.