Veenstra Jan A, Agricola Hans-Jürgen, Sellami Azza
CNIC UMR 5228 CNRS, Université Bordeaux 1, 33400, Talence, France.
Cell Tissue Res. 2008 Dec;334(3):499-516. doi: 10.1007/s00441-008-0708-3. Epub 2008 Oct 30.
Regulatory peptides were immunolocalized in the midgut of the fruit fly Drosophila melanogaster. Endocrine cells were found to produce six different peptides: allatostatins A, B and C, neuropeptide F, diuretic hormone 31, and the tachykinins. Small neuropeptide-F (sNPF) was found in neurons in the hypocerebral ganglion innervating the anterior midgut, whereas pigment-dispersing factor was found in nerves on the most posterior part of the posterior midgut. Neuropeptide-F (NPF)-producing endocrine cells were located in the anterior and middle midgut and in the very first part of the posterior midgut. All NPF endocrine cells also produced tachykinins. Endocrine cells containing diuretic hormone 31 were found in the caudal half of the posterior midgut; these cells also produced tachykinins. Other endocrine cells produced exclusively tachykinins in the anterior and posterior extemities of the midgut. Allatostatin-immunoreactive endocrine cells were present throughout the midgut. Those in the caudal half of the posterior midgut produced allatostatins A, whereas those in the anterior, middle, and first half of the posterior midgut produced allatostatin C. In the middle of the posterior midgut, some endocrine cells produced both allatostatins A and C. Allatostatin-C-immunoreactive endocrine cells were particularly prominent in the first half of the posterior midgut. Allatostatin B/MIP-immunoreactive cells were not consistently found and, when present, were only weakly immunoreactive, forming a subgroup of the allatostatin-C-immunoreactive cells in the posterior midgut. Previous work on Drosophila and other insect species suggested that (FM)RFamide-immunoreactive endocrine cells in the insect midgut could produce NPF, sNPF, myosuppressin, and/or sulfakinins. Using a combination of specific antisera to these peptides and transgenic fly models, we showed that the endocrine cells in the adult Drosophila midgut produced exclusively NPF. Although the Drosophila insulin gene Ilp3 was abundantly expressed in the midgut, Ilp3 was not expressed in endocrine cells, but in midgut muscle.
调节肽在果蝇黑腹果蝇的中肠中进行了免疫定位。发现内分泌细胞产生六种不同的肽：抑咽侧体素A、B和C、神经肽F、利尿激素31和速激肽。在支配中肠前部的咽下神经节的神经元中发现了小神经肽F（sNPF），而在中肠后部最末端的神经中发现了色素分散因子。产生神经肽F（NPF）的内分泌细胞位于中肠的前部和中部以及中肠后部的最前端。所有NPF内分泌细胞也产生速激肽。含有利尿激素31的内分泌细胞在中肠后部的后半部分被发现；这些细胞也产生速激肽。其他内分泌细胞仅在中肠的前部和后部末端产生速激肽。免疫反应性抑咽侧体素内分泌细胞存在于整个中肠。中肠后部后半部分的细胞产生抑咽侧体素A，而中肠前部、中部和后部前半部分的细胞产生抑咽侧体素C。在中肠后部的中部，一些内分泌细胞同时产生抑咽侧体素A和C。免疫反应性抑咽侧体素C内分泌细胞在中肠后部的前半部分特别突出。免疫反应性抑咽侧体素B/MIP细胞并不总是能被发现，即使存在，其免疫反应性也很弱，在中肠后部形成了免疫反应性抑咽侧体素C细胞的一个亚群。先前对果蝇和其他昆虫物种的研究表明，昆虫中肠中免疫反应性（FM）RF酰胺内分泌细胞可以产生NPF、sNPF、肌抑制素和/或磺基激肽。通过使用针对这些肽的特异性抗血清和转基因果蝇模型相结合的方法，我们表明成年果蝇中肠中的内分泌细胞仅产生NPF。尽管果蝇胰岛素基因Ilp3在中肠中大量表达，但Ilp3不在内分泌细胞中表达，而是在中肠肌肉中表达。
