The Pv11 cell line established from an African chironomid, Polypedilum vanderplanki, is the only cell line tolerant to complete desiccation. In Pv11 cells, a constitutive expression system for Pv11 cells was previously exploited and several reporter genes were successfully expressed. Here we report the identification of an effective minimal promoter for Pv11 cells and its application to the Tet-On inducible expression system. First, using a luciferase reporter assay, we showed that a 202 bp deletion fragment derived from the constitutively active 121-promoter functions in Pv11 cells as an appropriate minimal promoter with the Tet-On inducible expression system. The AcGFP1 protein was also successfully expressed in Pv11 cells using the inducible system. In addition to these reporter genes, avian myeloblastosis virus reverse transcriptase α subunit (AMV RTα), which is one of the most widely commercially available RNA-dependent DNA polymerases, was successfully expressed through the inducible expression system and its catalytic activity was verified. These results demonstrate the establishment of an inducible expression system in cells that can be preserved in the dry state and highlight a possible application to the production of large and complex proteins.

中文翻译：

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Tet-On诱导表达系统的无水生物细胞系Pv11的开发

由非洲手足动物Polypedilum vanderplanki建立的Pv11细胞系是唯一能完全干燥的细胞系。在Pv11细胞中，先前已开发了Pv11细胞的组成型表达系统，并成功表达了几种报告基因。在这里，我们报告为Pv11细胞有效的最小启动子的鉴定及其在Tet-On诱导表达系统中的应用。首先，使用萤光素酶报告基因检测，我们显示了从Pv11细胞中组成型有活性的121启动子起的202 bp缺失片段作为Tet-On诱导表达系统的适当最小启动子起作用。使用诱导系统，AcGFP1蛋白也成功地在Pv11细胞中表达。除了这些报告基因，禽成纤维细胞病病毒逆转录酶α亚基（AMVRTα）是最广泛的商业上依赖RNA的DNA聚合酶之一，已通过诱导表达系统成功表达，并证实了其催化活性。这些结果证明了可在干燥状态下保存的细胞中可诱导表达系统的建立，并突出了可能用于生产大而复杂的蛋白质。