ISOLATION AND PARTIAL DETERMINATION OF PRIMARY STRUCTURE OF A NEUROPEPTIDE OF BOMBYX MORI SHOWING SUMMER-MORPH-PRODUCING HORMONE ACTIVITY IN THE ASIAN COMMA BUTTERFLY,POLYGONIA C-AUREUM.

在家蚕脑-食管下神经节（Br-SG）提取物中发现一种神经肽，其活性与亚洲斑蝶（P.c-aureum）的促夏性激素相同。将家蚕Br-SG提取物中分子量为3-8 kD的SephadexG-50组分，分别在pH 5.6（或pH 6.9）的CM-、SP-、DEAE-和QAE-Toyoperal柱上进行柱层析，得到了与家蚕毒素相似的肽段。在pH 6.9时，SMPH活性肽与阴离子交换柱结合，而蚕毒素不与之结合。通过Mono-Q柱的阴离子交换层析，SMPH活性肽与蚕毒素在不同的组分中回收。将在Sephadex G-50柱后从Accell QMA柱洗脱的SMPH活性级分应用于反相HPLC，线性梯度为0-50%乙腈/50分钟SMPH活性在40-45%的乙腈，SDS-聚丙烯酰胺凝胶电泳只显示一条2.5-6 kD的主肽带，表明Br-2的SMPH活性与一种神经肽有关。家蚕B.mori成虫SG提取物与家蚕毒素的提取物不同。经阴离子交换层析和SDS-PAGE电泳进一步纯化神经肽。它们是使用由该赠款提供的仪器获得的。

A neuropeptide (s) showing the same activity as a summer-morph-producing hormone of the Asian comma butterfly, P.c-aureum, was found to exist in brain-suboesophageal ganglion (Br-SG) extract of the silkmoths, Bombyx mori. The peptide was almost the same molecular size with that of bombyxin activating the prothoracic glands of 4th-instar B.mori larvae in vitro.A Sephadex G-50 fraction of Br-SG extracts of B.mori involving molecules of 3-8 kD was applied on CM-, SP-, DEAE- and QAE- Toyoperal columns at pH 5.6 (or pH 6.9), respectively. The SMPH-active peptide was bound to, but bombyxin was not bound to, anion-exchange columns at pH 6.9.By anion-exchange chromatography with a Mono-Q column, the SMPH-activity was recovered in a different fraction from that of bombyxin. A SMPH-active fraction eluted from an Accell QMA cartridge following a Sephadex G-50 column was applied to a reversed-phase HPLC with a linear gradient of 0-50% acetonitoril/50 min (pH 6.9).The SMPH-activity was recovered in two fractions of 40-45% acetonitoril, where only one major peptide band of 2.5-6 kD was stained by SDS-PAGE.The results indicated that a neuropeptide responsible for SMPH-activity of Br-SG extracts of B.mori adults is different from that of bombyxin. The neuropeptide can be purified further by subjecting SMPH-active preparation to anion-exchange chromatography and SDS-PAGE.In addition, some other results was summarized in this reports. They were obtained using the instruments which were supplied by this grant.