Generation of stable Drosophila cell lines using multicistronic vectors.

Insect cell culture is becoming increasingly important for applications including recombinant protein production and cell-based screening with chemical or RNAi libraries. While stable mammalian cell lines expressing a protein of interest can be efficiently prepared using IRES-based vectors or viral-based approaches, options for stable insect cell lines are more limited. Here, we describe pAc5-STABLEs, new vectors for use in Drosophila cell culture to facilitate stable transformation. We show that viral-derived 2A-like (or "CHYSEL") peptides function in Drosophila cells and can mediate the multicistronic expression of two or three proteins of interest under control of the Actin5C constitutive promoter. The current vectors allow mCherry and/or GFP fusions to be generated for positive selection by G418 resistance in cells and should serve as a flexible platform for future applications.