Developmental and sexual differences of blood proteins in the silkworm, Bombyx mori

Acrylamide gel thin layer electrophoresis was used to study the development and distribution of blood proteins in the silkworm, Bombyx mori. More than twenty bands, the tremendous number of which has not yet been found so far, were demonstrated in the fifth larval instar and pupa. In the first and the early second larval instar one specific protein band, no. 18, was detected, and the band disappeared in the middle stage of the second instar. Two characteristic bands, nos. 11 and 21, were found to be predominating in younger instars. Concentration of the band 11 was gradually diminished and finally disappeared in the fourth instar, while the band 21 was still remained until the time of emergence although it was reduced in amount. Both number of bands and total amount of protein constituents were more remarkably and rapidly increased during the last fifth larval instar than any other stages of life cycle. The most striking change in the fifth instar was the appearance of bands 23 and 30. The second apparent change was the increase in concentration of proteins 19 and 26. The two distinct bands which might be called as larval female proteins (FL-1 and FL-2) were found in the middle and later stages of the fifth instar. After pupation slight change in electrophoretic pattern, compared with that of the late fifth instar, was observed except notably reduced amount of band 26 and the conversion of \u22female specific\u22 proteins. It is of interest that the larval female proteins disappeared completely just after pupation, and in turn a faster moving band was newly detected in female pupa which was absent in the male. So this new band stands for a pupal female protein (FP). As the pupal stage progressed, there was a general indication of decrease in the amount of major pupal proteins, followed by a sudden severe reduction on the day before emergence to remain in trace amounts. On the contrary, the band 34 increased rapidly in concentration at the time of emergence and served as the main fraction of the adult moth. This simultaneous changes of blood proteins during life cycle of the silkworm provided a detailed example of the logical assumption that the biochemical development of proteins precedes the more obvious morphological changes in metamorphosis.カイコの1令から成虫までの発育,変態に伴う体液蛋白成分の変化を,acrylamide gelを用いる薄層電気泳動法で調べ,次の結果を得た. 1. カイコの体液蛋白成分は発育に伴つて変化するが,5令壮蚕期から蛹期にかけて量的にも成分数でも最大に達する.泳動分離帯は5令壮蚕期で21～22成分,蛹期で22～23成分に及んだ. 2. 体液蛋白の泳動パターンは4令期を境に稚蚕型と壮蚕型とに分かれる.稚蚕型はさらに2令期蚕までと同令食桑期以降とで2型に分かれる.蜥期は5令壮蚕期と大差ない.成虫では特異的な1成分が増加するが,蛹期における主要成分のほとんどが著しく減少あるいは消失している.すなわち体液蛋白の変換期は, 1) 2令食桑期, 2) 4令期, 3) 成虫化前日の3期である. 3. 5令中期以降では泳動パターンが雌雄により異なる.5令中期から前蛹期までは幼虫型雌蛋白が2成分,化蛹後はそのいずれとも異なる蛹型雌蛋白1成分が検出される.雌特異蛋白について言えば,その変換期は化蛹脱皮期である