Truman J W, Booker R
J Neurobiol. 1986 Nov;17(6):613-25. doi: 10.1002/neu.480170606.
The segmental ganglia of adults of the moth, Manduca sexta, are constructed both from remodeled larval neurons and from adult-specific cells. The latter are produced by identified stem cells (neuroblasts) during larval life and then differentiate to form functional neurons during metamorphosis. The mitotic activity of the larval neuroblasts could be irreversibly blocked by the DNA-synthesis inhibitor hydroxyurea (HU). Treatment on day 1 of the third larval stage resulted in 80-90% of the neuroblasts being blocked before they produced any progeny while leaving the functional larval neurons unaffected. Treated larvae finished growth, underwent metamorphosis, and produced an adult CNS that contained the normal set of remodeled larval neurons but lacked most of the new adult-specific cells. When HU treatment was delayed until the start of the fourth or fifth larval stage, the neuroblasts produced the early portions of their respective lineages before they were blocked. The immature neurons that were generated prior to treatment survived to contribute adult-specific neurons to the moth CNS, but the remainder of each lineage was missing. This technique therefore enables one to produce adult nervous systems containing the basic set of remodeled larval cells plus defined sets of adult-specific neurons.
烟草天蛾成虫的节段神经节由重塑的幼虫神经元和成虫特异性细胞构成。后者由幼虫期已确定的干细胞（神经母细胞）产生，然后在变态过程中分化形成功能性神经元。幼虫神经母细胞的有丝分裂活性可被DNA合成抑制剂羟基脲（HU）不可逆地阻断。在幼虫第三龄期第1天进行处理，80% - 90%的神经母细胞在产生任何后代之前就被阻断，而功能性幼虫神经元不受影响。经处理的幼虫完成生长、经历变态，并产生一个成年中枢神经系统，其中包含正常的一组重塑幼虫神经元，但缺少大部分新的成虫特异性细胞。当HU处理推迟到第四或第五龄期开始时，神经母细胞在被阻断之前产生了各自谱系的早期部分。处理前产生的未成熟神经元存活下来，为烟草天蛾中枢神经系统贡献成虫特异性神经元，但每个谱系的其余部分缺失。因此，这项技术能够使人产生包含基本的一组重塑幼虫细胞以及特定的成虫特异性神经元组的成年神经系统。
