(A) SeHex and (B) SeSP1 transcript analysis by RT-PCR amplification after dsRNA injection. Three larval states (before death, still living and less vital) were randomly selected at each time point after injection. Total RNA was extracted and reversed to cDNA using AMV reverse transcriptase (Takara). SeHex and SeSP1 specific probes were radiolabeled with [α-32P]-dCTP. The specific primers SeHex-FP and SeHex-RP or SeSP1-FP and SeSP1-RP were used to amplify cDNAs in the same PCR reactions. The PCR products were separated on 2% agarose gel and transferred to a Hybond-N+ nylon membrane. Hybridization, washing and signal detection of the blots were carried out as described previously. (A) Lanes marked 12 h (5L2), 24 h (5L3), 36 h (5L3), 48 h (W), 72 h (P1), 96 h (P2) and120 h (P3) indicate the times (and developmental stage) after injection. (B) Lanes marked 12 h (5L2), 24 h (5L3), 36 h (5L3), 48 h (W), 72 h (P1) and 96 h (P2) indicate the times (and developmental stage) after injection. The housekeeping gene β-actin was used as a reference.