When heat shock induces expression at 4-5 hours AEL (stage 7-9), before the singling out of the progenitor cell has occurred, the final muscle pattern is not much affected. The specific loss of muscles DA3A/DO5A only occurs on average in one segment in half of the embryos. This loss is likely due to as defect in singling out the DA3A/DO5A progenitor. When heat shock induces expression at 5-7 hours AEL (stage 10-11) larval muscle pattern is normal.
Expression of knhs.PS using heat shock between 3 and 5 hours after egg laying (stages 6 to 9) causes embryonic death. The embryos have a normal segmental array of thoracic and abdominal denticles but have a disrupted head skeleton; the H-piece is missing and the lateralgraten are abnormal.
