Figure 1.
Expression of Manduca DALP. (A) A developmental Northern blot of ISM RNA was hybridized with 32P-labeled DALP cDNA. ISMs become committed to die late on day 17 and begin to die during the hours after adult emergence late on day 18. Treatment of day-17 animals with 25 μg of the steroid 20-hydroxyecdysone (20 HE) delays both ISM death and the expression of death-associated transcripts (11). d, day of pupal-adult development; hr, hours post-adult emergence (PE). (B) Western blot of ISM proteins during the period before and after the onset of cell death. Arrow indicates the migration of DALP that was developmentally regulated. The identity of the higher molecular weight, constitutively expressed proteins is unknown. Protein markers are in kDa.