Molecular physiology on ion transport sytems in silkworms

蚕离子传输系统的分子生理学

基本信息

批准号：
06454069
负责人：
AZUMA Masaaki
金额：
$ 3.14万
依托单位：
Tottori University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06454069/
关键词：
silkworm midgut amino acid transport V-ATPase Potassium pump Proton pump silk gland Bombyx mori

项目摘要

Insect midgut in Lepidoptera (the main part of the alimentary canal) is a central and indispensable tissue to exchange various ionic solutes across the epithelia and to maintain the cellular activity and the tissue functions (s). We have investigated such a mechanism to understand the ionic homeostasis and osmoregulation in the silkworm system. Results ar as follows :(1) Immunocytochemical studies were done with the specific anitibody against V-ATPase. In silkwrms, V-ATPase can be detected in the midgut, the Malpighian tubules, the salivary gland and the silk gland. V-ATPase in each tissue was located at the cell surface, suggesting that silkworm V-ATPase is a plasma membrane-type not an endomenbrane-type.(2) In the silk gland, V-ATPase seems to contribute to produce an acidic milieu in the glandular lumen. This shows highly contrast to the midgut lumen, which produce an extremely high alkalinity (pH 11-12).(3) The silk gland V-ATPase is quite similar to other animal V-ATPases in the common subunits of V-ATPase.(4) K+/amino acid symporter in the midgut was rather labile protein and hard to purify. Its molecular nature still remains unknown.(5) The silk gland is highly active tissue for silk protein syntesis and secretion. This implies that the tissue needs much supply of amino acids from the haemolymph to synthesize the silk protein. Thus, it is coming up as the quite near future subject to survey the K+/amino acid symporter in the silk gland. This would be expected as the breakthrough for identifing the K+/symporter molecule (s).

鳞翅目中的昆虫中肠（消化道的主要部分）是一种中心且必不可少的组织，可在上皮层上交换各种离子溶质并维持细胞活性和组织功能（S）。我们已经调查了一种理解蚕系统离子稳态和渗透调节的机制。结果AR如下：（1）针对V-ATPase的特异性抗体进行了免疫细胞化学研究。在Silkwrms中，可以在Midgut，Malpighian小管，唾液腺和丝绸腺体中检测到V-ATPase。每个组织中的V-ATPase位于细胞表面，表明蚕V-ATPase是质膜类型，而不是内骨型型。（2）在丝绸腺体中，V-ATPase似乎有助于在腺体流明中产生酸性环境。这与中肠口腔高度对比，后肠腔产生极高的碱度（pH 11-12）。（3）丝腺V-ATPase与V-ATPase共同亚基中其他动物V-ATP酶非常相似。（4）Midgut中k+/氨基酸分类剂在中肠中相当不稳定的蛋白质和硬质量。它的分子性质仍然未知。（5）丝绸是用于丝蛋白语法和分泌的高度活性组织。这意味着组织需要大量的氨基酸供应，从血液伴有合成丝绸蛋白。因此，它是在近来的近年中进行调查的丝绸腺中的K+/氨基酸分类蛋白。这是鉴定K+/Symporter分子的突破。