Kawasaki Hideki, Manickam Asaithambi, Shahin Rima, Ote Manabu, Iwanaga Masashi
Faculty of Agriculture, Utsunomiya University, 350 Mine, Utsunomiya, Tochigi 321-8505, Japan.
Faculty of Agriculture, Utsunomiya University, 350 Mine, Utsunomiya, Tochigi 321-8505, Japan.
Gene. 2018 Jan 5;638:26-35. doi: 10.1016/j.gene.2017.09.031. Epub 2017 Sep 21.
The present study was conducted to clarify the involvement of the basement membrane (BM) in insect metamorphosis through analysis of the expression profile of two types of metalloproteinase (MMP and ADAMTS) genes in several organs, their ecdysone involvement, and the histological change of BM. BM was observed around wing sac and in the wing cavity and around fat bodies at the W0 stage but disappeared after the W3 stage, and wing discs evaginated and fat body cells scattered after the W3 stage. The disappearance of the BM of midgut and silk glands was not observed after the W3 stage, but degenerated epithelium cells in the midgut and shrunken cells in the silk gland were observed after the W3 stage. BmMMP1 showed a peak at P0 in the wing discs, fat bodies, midgut, and silk gland. BmMMP2 showed a broad peak around pupation in the wing discs, fat bodies, midgut, and silk gland. BmADAMTS-1 showed enhanced expression at W2 in the wing discs, fat bodies, midgut, and hemocyte, while BmADAMTS-L showed enhanced expression at W3 in the fat bodies, midgut, silk gland, and hemocyte. After pupation, they showed a different expression in different organs. All of four genes were induced by 20-hydroxyecdysone in wing discs in vitro. The present results suggested the involvement of MMPs and ADAMTS in the BM digestion and the morphogenesis of organs during Bombyx metamorphosis.
本研究旨在通过分析几种器官中两种金属蛋白酶（MMP和ADAMTS）基因的表达谱、它们与蜕皮激素的关系以及基底膜（BM）的组织学变化，来阐明基底膜在昆虫变态中的作用。在W0阶段，在翅芽周围、翅腔和脂肪体周围观察到基底膜，但在W3阶段后消失，并且在W3阶段后翅盘外翻，脂肪体细胞分散。在W3阶段后未观察到中肠和丝腺基底膜的消失，但在W3阶段后观察到中肠上皮细胞退化和丝腺细胞萎缩。BmMMP1在翅盘、脂肪体、中肠和丝腺中的P0期出现峰值。BmMMP2在翅盘、脂肪体、中肠和丝腺中化蛹前后出现一个较宽的峰值。BmADAMTS-1在翅盘、脂肪体、中肠和血细胞中的W2期表达增强，而BmADAMTS-L在脂肪体、中肠、丝腺和血细胞中的W3期表达增强。化蛹后，它们在不同器官中表现出不同的表达。在体外，所有这四个基因在翅盘中均受20-羟基蜕皮激素诱导。目前的结果表明，MMPs和ADAMTS参与了家蚕变态过程中基底膜的消化和器官的形态发生。
