A heat-shock induced pulse of Krhs.PS expression just before the birth of the U3 lineage results in a high proportion of hemisegments having ectopic U3 neurons. Progressively later pulses of Krhs.PS expression generate a decreasing frequency of ectopic U3 neurons.
Embryos expressing Krhs.PS using heat shock between 4 to 6 hours after egg laying develop additional Malpighian tubule tip cells.