Table 2.
Concentration of IPTG | |||||||
Test gene | Experimental phenotype | 0 | 1 pM | 1 nM | 1 μM | 1 mM | 10 mM |
unc-37 | Emb | 0% | 4% | 11% | 48% | 100% | 77% |
Unc | 0% | 10% | 10% | 100% | NA | 69% | |
hlh-2 | Emb | 0% | 8% | 20% | 97% | 100% | 86% |
Unc | 0% | 13% | 9% | 100% | NA | 100% | |
mei-1 | Emb | 0% | 7% | 16% | 71% | 100% | 71% |
Male | 0% | 0% | 6% | 8% | NA | 3% | |
rba-2 | Emb | 56% | 100% | 100% | 100% | 100% | 100% |
Four genes were tested to determine whether reducing the concentration of IPTG used to induce the bacteria could elicit hypomorphic phenotypes from worms escaping embryonic lethality. The percentage of embryonic lethality (Emb) was determined from the total number of progeny, whereas the percentage of uncoordinated (Unc) or male worms was determined from escapers only. High concentrations of IPTG (for example 10 mM) overinduce and presumably kill the bacteria, thus leading to a lower penetrance of strong phenotypes. Data shown represent the progeny of three fed worms. NA, not applicable.