The induction of lysosomal enzyme activity in the fat body of Calliphora erythrocephala: Changes in the internal environment |
| |
Authors: | Elizabeth van Pelt-Verkuil |
| |
Institution: | Zoölogisch Laboratorium, Vakgroep Celbiologie en Morfogenese, Kaiserstraat 63, 2300 RA Leiden, The Netherlands |
| |
Abstract: | The activity of the lysosomal marker enzyme acid phosphatase in the larval fat body of Calliphora erythrocephala increases during development, but not at the same rate throughout the tissue. During the feeding stage, the posterior region has a higher acid phosphatase activity than the anterior region. When the larvae cease feeding on the 5th day of development, the acid phosphatase activity of the inactive anterior lobe increases rapidly in a mosaic-cell pattern. When 4-day-old feeding stage larvae are starved, this increase occurs one day earlier than normally. After the emptying of the gut, the acid phosphatase activity of all the anterior cells both in normal and in starved larvae exceeds that of those in the posterior region.Transplantation experiments indicate that the induction of acid phosphatase activity in the fat body during normal development, especially in the anterior region, is caused by a change in the internal environment when the larvae cease feeding. Both RNA and protein synthesis are involved in this induction process. Inductive factors are present in 5-day-old larvae as well as during formation of the puparium. The competence of the feeding-stage fat cells to develop high acid phosphatase activity is acquired before the actual induction takes place. |
| |
Keywords: | Present address to which requests for reprints should be sent: Gaubius Institute Health Research Organization TNO Herenstraat 5d 2313 AD Leiden The Netherlands |
本文献已被 ScienceDirect 等数据库收录! |
|