Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2000: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1999: ¥1,200,000 (Direct Cost: ¥1,200,000)
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Research Abstract |
In order to know the structure of alkaline phosphatase (ALP) genes in the silkmoth, Bombyx mori, genomic clones each for mALP and sALP were independently isolated. Both genes, however, were located to a small genomic region (11,495bp) presumably on III chromosome. There were an intervening sequence (4,341bp) between them. The direction of transcription were the same : the mALP gene was located to upstream of the sALP gene. The mALP gene has five exons, but the sALP gene has four. This difference is involved in no intron corresponding to the mALP second one in the sALP gene. The nucleotide sequence of each exon were highly identical (60-80%) between them. On the other hands, there was no significant homology in their introns, although their relative positions accorded well. RNA blot analysis demonstrated that a 2.2Kb mRNA from the mALP gene and two transcripts, 2.0Kb and 2.4Kb, from the sALP gene appeared first just before hatching. The amounts of all three transcripts reached their maxima at the 6th day of the fifth instar larval stage and they disappeared rapidly in the metamorphic stage. Accordingly, their transcriptions are temporally specific for the existence of the larval midgut epithelium, thus the feeding activity of B.mori, although the appearance profiles and the disappearing stages of their transcription were not completely the same : sALP transcripts increased slower than that of mALP in embryogenesis and disappeared a few days earlier than that of mALP at the end.
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