| Project/Area Number |
62304018
|
|---|
| Research Category |
Grant-in-Aid for Co-operative Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
蚕糸学
|
|---|
| Research Institution | KYUSHU UNIVERSITY |
|---|
Principal Investigator |
KOGA Katsumi Kyushu University, Fac. Agr., Professor, 農学部, 教授 (40038261)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YAMASHITA Okitsugu Nagoya University, Fac. of Agr., Associate professor, 農学部, 助教授 (50023411)
OHNISHI Eiji Nagoya University, Fac. of Sci., Professor, 理学部, 教授 (60022521)
SONOBE Haruyuki Konan University, Fac. of Sci., Associate professor, 理学部, 助教授 (20068133)
FUJII Hiroshi Kyushu University, Fac. Agr., Associate professor, 農学部, 助教授 (10038268)
SOEDA Eiichi The Institute of Physical and Chemical Research, ジーンバンク, 研究員 (00039330)
坂口 文吾 九州大学, 農学部, 教授 (30038161)
|
|---|
| Project Period (FY) |
1987 – 1988
|
| Project Status |
Completed (Fiscal Year 1988)
|
| Budget Amount *help |
¥6,000,000 (Direct Cost: ¥6,000,000)
Fiscal Year 1988: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 1987: ¥3,200,000 (Direct Cost: ¥3,200,000)
|
|---|
| Keywords | Silkworm eggs / Embryognesis / Diapause break / Ecdysteroids / Yolk proteins / Esterase A / エステラーゼA / 限定分解プロテアーゼ / 形質発現制御 / 発生マーカー |
|---|
| Research Abstract |
The method for extraction of translatable messenger RNA from the eggs of Bombyx mori was established. By using the latter method the mode of switchover of aldolase isozymes, chosen as a marker for gene expression study, could be clarified. Based on the effort to set up the human project, i.e. aiming at the sequencing of the whole genome of man, the scope of preparing the cDNA and genomic libraries of the silkworm was proposed. As to the major yolk protein named egg specific protein (ESP), the relevant transcription, translation and posttranslational processing were precisely analyzed. Moreover, the way of yolkprotein utilization has begun to be uncovered; a specific protease which can degrade ESP was found to be present. This enzyme exhibit a limited break of the ESP chain. This provides the first understanding of the initial steps of yolk protein utilization at the molecular level. The presence of ovarian ecdysteroids has been known. The major species were found to be conjugate types,
… More
which may be the storage forms and hydrolysis enzymes detected in the present study might have critical roles to provide free, thus active, ecdysteroids during embryogenesis. The initiation of diapause in B. mori is known to be controlled by a single gene pnd^+. The product of the latter gene was suggested to be a protein as separated by two-dimensional gel electrophoresis. The mode of action of the latter gene (and its product) was discussed in terms of protein synthesis and RNA synthesis at the period of diapause onset. As to the break of diapause a signal of the end of the so-called diapause development has been found to be the activation of esterase A. This enzyme was crystallized and revealed to be a time-measuring molecule which activates itself in vitro under the specified conditions minicking the cold activation of diapausing eggs of the silkworm. The nucleotide bases in particular 5-methylcytosine changed the hibernating program of the silkworm eggs. These agents might serve as convenient experimental drugs that disturb the diapasue system to be analyzed. Less
|
