Lysozyme in the midgut of Manduca sexta during metamorphosis.
Lysozyme in the midgut of Manduca sexta during metamorphosis.
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变态期间天蛾中肠中的溶菌酶。
DOI：
10.1002/arch.940170202
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发表时间：
1991
影响因子：
2.2
通讯作者：
Dunn,PE
中科院分区：
文献类型：
--
作者：
Russell,VW;Dunn,PE
低水平的溶菌酶被发现在中肠上皮的烟草天蛾，天蛾，在早期的第五个幼虫体育场。这在对照昆虫以及细菌攻击的昆虫中观察到。没有检测到溶菌酶的肠道内容物中的任何一组的昆虫，这是积极地吃或在早期阶段的变态。然而，后来在体育场从昆虫身上收集的中肠组织匀浆中检测到了高水平的溶菌酶活性。免疫细胞化学研究表明，在幼虫-蛹蜕皮期间，溶菌酶积累在中肠再生细胞的大顶端空泡中。这些细胞，最初分散在整个幼虫中肠上皮的基底，繁殖并形成一个连续的细胞层下的幼虫中肠细胞。在幼虫/蛹蜕皮时，幼虫中肠上皮脱落，再生细胞（现在形成中肠的单细胞层）将其空泡内容物释放到中肠腔中。这种释放导致蛹中肠内腔中的高溶菌酶活性，并被认为可以保护免受细菌感染。这是第一个迹象表明，在没有细菌感染的情况下，溶菌酶基因可能在特定组织中受到发育调控。
Low levels of lysozyme were found in the midgut epithelium of the tobacco hornworm,Manduca sexta, during the early part of the fifth larval stadium. This was observed in control insects as well as in bacterially challenged insects. No lysozyme was detected in the gut contents of either group of insects which were actively eating or in the early stages of metamorphosis. However, high levels of lysozyme activity were detected in homogenates of midgut tissue collected from insects later in the stadium. Immunocytochemical studies demonstrated that lysozyme accumulates in large apical vacuoles in regenerative cells of the midgut during the larval‐pupal molt. These cells, initially scattered basally throughout the larval midgut epithelium, multiply and form a continuous cell layer underneath the larval midgut cells. At the larval/pupal ecdysis the larval midgut epithelium is sloughed off and the regenerative cells, now forming the single cell layer of the midgut, release the contents of their vacuoles into the midgut lumen. This release results in high lysozyme activity in the lumen of the pupal midgut and is thought to confer protection from bacterial infection. This is the first indication that the lysozyme gene may be developmentally regulated in a specific tissue in the absence of a bacterial infection.