MMS integration
(both methods modified by Herman
Lab)
NOTES: - Remember that MMS is a potent mutagen -- wear gloves and be very
careful.
- Integration is best done using an array that is transmitted at very
low frequency.
- MMS has a short aqeuous half-life
Henderson Method -- approx. 1-5% integrants
- Make a solution of 0.1% (1
l in 1
ml) MMS in M9.
- Put 100
l of 0.1% MMS in a thumb
depression plate.
- Pick 35-40 L4 non-Uncs into the 0.1% MMS.
- Incubate for 10 min at room temperature (RT).
- Transfer mutagenized worms to individual plates
(TIP).
- Rinse all items with LOTS of water.
- Pick 100-120 F1 L4/YA non-Uncs TIP.
- Pick 6 L4/YA non-Uncs TIP from 100 F1 plates (total 600 F2
plates). Don't try to score plate for % transmission.
- Screen F2 plates for 95% non-Uncs.
- Pick 6 L4/YA non-Uncs TIP from F2 candidate plates.
- Screen F3 plates for 100% non-Uncs. The stack of six plates should all
be close to 100% at this point.
- Pick 6 L4/YA non-Uncs TIP from F4 candidate plates.
- All six F4 plates should be 100% non-Uncs.
- Start backcrossing.
Koelle Method -- approx. 1-3% integrants
- Make a solution of 0.1% (1
l in 1
ml) MMS in M9.
- Transfer 150 L4 non-Uncs to a plate.
- Wash worms off using M9 into a 1.7 ml bullet.
- Spin in mini centrifuge 20-30 sec.
- Remove supernatant.
- Add 100
l of 0.1% MMS solution.
- Incubate for 10 min at room temperature (RT).
- Transfer mutagenized worms to individual plates
(TIP).
- Rinse all items with LOTS of water.
- Pick 520 F1 L4/YA non-Uncs TIP over two days.
- Pick 2 F2 L4/YA non-Uncs TIP from each F1 plate. Need to pick
1030-1050 plates since 3-5 % of worms are dead or sterile. Don't try to
score plates for % transmission but if one looks close to 100% pick 4 F2
TIP. Don't label plates; keep each generation in labeled boxes.
- Screen F2 plates for 95% non-Uncs over two to three days (18-20
hours).
- Pick 4 L4/YA non-Uncs TIP from F2 candidate plates.
- Screen F3 plates for 100% non-Uncs. The stack of four plates should
all be 100% at this point.
- Pick 4 L4/YA non-Uncs TIP from F4 candidate plates.
- Confirm 100% non-Uncs and start backcrossing.
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