Inducible expression of green fluorescent protein within channel catfish cells by a cecropin gene promoter
Document Type
Article
Publication Date
8-17-1998
Abstract
The activity of an insect promoter of the cecropin B gene (Cec B) was investigated using green fluorescent protein (gfp) as a reporter in cells of channel catfish (Ictalurus punctatus). The expression vector pQZ-1 containing the Cec B promoter and a modified gfp cDNA sequence was delivered by lipofection to three catfish cell types: fibroblast and leukocyte cell lines, and primary cultures of leukocytes. No resistance genes were included in the vector for selection of GFP-expressing cells. The GFP mRNA was detected in all three cell types with 5 to 10 times higher concentrations observed in leukocytes than in fibroblasts. Expression was enhanced with the addition of irradiated Flavobacterium columnare (7.0 x 106 cells/ml) or Escherichia coli LPS (125 μg/ml). Quantitative RT-PCR showed GFP mRNA reached maximum levels 24 h after bacterial challenge in fibroblast cells, and at 10-12 h after LPS challenge in fibroblasts and leukocytes. The number of fibroblasts expressing GFP increased by 0.8%, and the average of green fluorescence intensity increased by 52.8%, whereas the increase in leukocytes was 0.13% in cell number and 3.4% in fluorescence intensity. These results suggest that the transcription of the Cec B promoter in channel catfish cells exhibited an inducible pattern and could be placed under the control of the immune system (in vivo). The mechanisms for endogenous activation of the Cec B promoter and for production of gfp RNA in unchallenged cells remain to be studied.
Publication Source (Journal or Book title)
Gene
First Page
207
Last Page
213
Recommended Citation
Zhang, Q., Tiersch, T., & Cooper, R. (1998). Inducible expression of green fluorescent protein within channel catfish cells by a cecropin gene promoter. Gene, 216 (1), 207-213. https://doi.org/10.1016/S0378-1119(98)00272-8