Summary: | 碩士 === 國立臺灣大學 === 園藝學研究所 === 84 === ACC oxidase is the last enzyme involved in the ethylene bio-
synthetic pathway,which converts 1-aminocyclopropane-1-carboxylic
acid to ethylene. To isolate the gene encoding ACC oxidase from
banana (Musa spp. AAA), we used the cDNA clone pBEPM3 and PCR
fragment BEFEYSF as probes for genomic library screening. After
screening, 303 positive plaques were isolated from one million
plaques and 45 independent clones were purified. Among purified
clones, 14 clones were further characterized and could be divided
into five groups, based on Southern blot analysis and restriction
endonuclease mapping. Four groups are correspouding to pBEPM3 and
the fifth group to BEFEYSF. λBGE1, a clone beloning to the first
group, was sequenced and contained two inversely repeated genes
designated BGE-EFE1A and BGE-EFE1B. Between these two genes there
is only one base pair difference in the gene body and 274 base
pairs are indetical in the upstream region starting from trans-
lation start site. Both 1A and 1B genes possess 3 exons and are
interrupted by 2 introns and share 99.8% homology to pBEPM3,
respectively. The 5'-flanking region of two genes is located in
the middle of two genes spanning about 3.1 kb. To analyze the
promoter activity by the biolistic method, the 3.1 kb promoter
fragment was fused to GUS reporter gene in each orientation and
was expressed in the petals of Phalaenopsis. GUS activity was
demonstrated in the transient gene expression assay for both BGE-
EFE1A and BGE-EFE1B genes.
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