suggestions for maintenance of a possibly novel evl /scr/FGFR mutant


In an EMS-induced mutant screen for taxis mutants, I also picked up a couple of mutants with an interesting phenotype (unrelated to taxis) that caught my interest.

The F3 worms exhibit a mixed phenotype; some are so severely affected that they fail to lay eggs and died in less than 24 hours (Their demise might also be attributable to how rough the transfer was from plate to plate, e.g. perhaps the vulva ruptured?). Of the survivors, all have in common that they are small (more like L3 worms) scrawny (?scr), translucent and have an abnormally everted vulva(?evl). One of the mutants is more severely affected than the other, is sickly and has laid perhaps 6-7 eggs and there are 5 L1-L2 worms of the same plate. the second mutant is not as severe, has laid perhaps 20 eggs and I count about 15 L1-L2 worms.

I would like to keep these mutants going but the signs are (from worms taken off the same F2 plate where these two F3 mutants came from), that they are fragile, lay very few eggs and develop slowly.

Reading the egl-15 papers and more egenerally the literature on FGFR-related mutants, I have decided to keep the mutants at 15 degrees just in case the mutation is temperature sensitive?? Is this sensible?

Any other suggestions would be most welcome as I think it is not clear whether the few worms I have still will survive long enough to produce offspring…and it would be a shame not to find out what the mutation is!



hey steve,
keeping the strain going sounds fairly challenging. if it does have hyperactivated fgf signaling maybe you could rescue it by doing RNAi against soc-1?
but if that doesn’t work, just pick a few worms for use with the Qiagen repli-g kit and then you could do WGS whenever you want.

Will it mate with males and produce cross-progeny? If so, you could keep it going as a heterozygous stock (until you could balance it somehow) and even freeze it down that way.

Hi Eric / Maduro,

thanks to both of you for the suggestions. Eric, the idea of rescuing it using RNAi is in principle a good one, but I fear that by the time we had set up such a rescue (materials etc) it would be all over. The WGS idea is probably the last resort as actually carrying out the WGS is quite an investment.

Maduro, we are currently setting up the male mating with exactly the idea of doing what you suggest…I hope that the hermaphrodites are able to mate.