DEVELOPMENT OF LIVING COLOR TRANSGENIC MEDAKA LINES FOR BIOMONITORING AQUATIC CONTAMINATION

Abstract

Here we report the generation of two biomonitoring transgenic medaka lines using a stress-inducible promoter, hsp70, and xenobiotic inducible promoter, cyp1a, to express the GFP reporter gene and these two transgenic lines are Tg(hsp70:gfp) and Tg(cyp1a:gfp) respectively. A fairly novel transposon tool in fish transgenesis, maize Ac/Ds, was used to aid the generation of these transgenic medaka. High germline transmission rates and classic features of Ac/Ds transposon system were observed, hence demonstrating the high efficiency of Ac/Ds to aid transgene integration in medaka. Both Tg(hsp70:gfp) and Tg(cyp1a:gfp) medaka were exposed to various chemicals to determine their inducibility and sensitivity. Tg(hsp70:gfp) responds mainly to heavy metals such as mercury, arsenic and cadmium while Tg(cyp1a:gfp) responds mainly to polycyclic aromatic hydrocarbon (PAH) and dioxin groups such as 3-methylcholanthrene, benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzodioxin. These observations indicate the feasibility of using Tg(hsp70:gfp) as indicator for heavy metal contamination and Tg(cyp1a:gfp) as indicator for PAH contamination.