Larval fat body cells die during the early pupal stage in the frame of metamorphosis remodelation in Bombyx mori
Larval fat body cells die during the early pupal stage in the frame of metamorphosis remodelation in Bombyx mori
复制标题
DOI：
10.1016/j.jinsphys.2011.09.013
复制
发表时间：
2011-12-01
影响因子：
2.2
通讯作者：
Sakurai, Sho
中科院分区：
文献类型：
--
作者：
Kaneko, Yu;Yasanga, Thippawan;Sakurai, Sho
在全代谢昆虫中，幼虫脂肪体的形态在变态过程中被重塑。在高等双翅目中，脂肪体的重塑是通过幼虫脂肪体细胞的死亡和成年脂肪体与原始细胞的分化来实现的。然而，对鳞翅目昆虫化蛹过程中脂肪体的重塑知之甚少。在本研究中，我们发现家蚕幼虫脂肪体的细胞死亡发生在化蛹后不久。化蛹后第1、2天，约有30%的脂肪小体细胞死亡。细胞死亡涉及基因组DNA的碎裂，这是细胞凋亡的一个特征。手术操作和脂肪体细胞的体外培养表明，20-羟基蜕皮激素和保幼激素对细胞死亡的开始或进展都没有影响。在细胞死亡过程中，细胞死亡的关键酶caspase-3的活性显著增加。对类caspase-3蛋白活性形式的Western印迹分析表明，家蚕caspase-3的长度远大于其他物种的caspase-3。这些结果表明，家蚕幼虫的脂肪体细胞是通过细胞死亡而被清除的，这种死亡可能是由一个新的家族的半胱氨酸天冬氨酸酶介导的。(C)2011爱思唯尔有限公司。保留所有权利。
In holometabolus insects, morphology of the larval fat body is remodeled during metamorphosis. In higher Diptera, remodeling of the fat body is achieved by cell death of larval fat body cells and differentiation of the adult fat body from primordial cells. However, little is known about remodeling of the fat body at pupal metamorphosis in Lepidoptera. In this study, we found that cell death of the larval fat body in Bombyx mori occurs at shortly after pupation. About 30% of the fat body cells underwent cell death on days 1 and 2 after pupation. The cell death involved genomic DNA fragmentation, a characteristic of apoptosis. Surgical manipulation and in vitro culture of fat body cells revealed that 20-hydroxyecdysone and juvenile hormone had no effect on either initiation or progression of cell death. During cell death, a large increase in activity of caspase-3, a key enzyme of cell death, was observed. Western blot analysis of the active form of caspase-3-like protein revealed that the length of caspase-3 of B. mori was much larger than that of caspase-3 in other species. The results suggest that larval fat body cells of B. mori are removed through cell death, which is mediated by a caspase probably categorized in a novel family. (C) 2011 Elsevier Ltd. All rights reserved.