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From 2012.igem.org

Auxin toxicity test in tadpoles

The purpose of this experiment

Before testing our AID system (see AID system), we conducted auxin toxicity test. Auxin concentrations used were 500, 250, 125 and 0 µM dissolved in MMR, with renewal of the medium each morning. (see medium preparation here )

Result interpretation:

The survival rate of embryos in both 1-naphthaleneacetic acid (NAA) and indole-3-acetic acid (IAA) were observed during three days of experiment.
As a control sample, embryos were placed in MMR 0.1x medium without an auxin.
The embryo's mortality rate was about: for NAA 23% for D1 and 45% for D2
for IAA 20% for D1 and 51% for D2

However embryos mortality depends not only on the auxin presence in media, but also on the rearing conditions, frequency of sorting dead and live embryos and media's changing. Usually the normal mortality ratio is no bigger than 30%.
We are aware that our experiment should be repeated to calculate the error deviation. But even without this data we confirmed our hypothesis that presence of auxin in MMR medium is not toxic for embryos and it doesn't cause any morphological abnormalities.

Data:

Discussion

The number of embryos (D0) and tadpoles (D1-D2) decrease globally in NAA and IAA for the different gradients. Compare to the control, NAA addition in the media doesn’t seem to affect tadpoles survival. The same observation for IAA addition since there isn’t correlation between tadpoles death and the gradient addition of IAA. Contrary to what it could be expected, for the last day, an important rate of tadpoles died in Auxin media as well as in control. It’s probably linked to the state of our plates. They weren’t changed and the dirty could have killed the tadpoles.

Results

For the first time a plant hormone expression is implemented in a complex system. The auxin toxicity test (IAA and NAA) was made in order to determine the suitable auxin concentration for its use in tadpoles. According to the results we can’t assume an auxin toxicity in tadpoles.