Figure 3. Transcriptional and translational expressions of Sona during development and active form of Sona in S2 cell culture.

(a) Expression of sona transcripts during development detected with the probe representing 732^th to 1920^th nucleotides of the sona-RA cDNA. sona-RA transcript is marked with an arrow. E1, AEL (After egg laying) 0~12 hr; E2, AEL 12~24 hr; L1,2, first and second instar larvae; L3, late third instar larvae; P1, early pupae; P2, mid pupae; P3, late pupae; AB, adult body; AH, adult head. (b) Expression of Sona protein during development. E1, AEL 0.5~11 hr; E2, AEL 16~24 hr; L1, first instar larvae; L3, late third instar larvae; P, late pupae; AM, adult male; AF, adult female. The arrow indicates the full-length Sona-PA form. (c) The cellular extract was obtained from the late 3^rd instar larvae raised at 18 °C and then at 29 °C for 24 hrs until dissection. C is actin-Gal4 (act) >Gal80^ts, (1) is act > sona RNAi-1; Gal80^ts, and 2 is act > sona RNAi-2; Gal80^ts. (d,e) Sona proteins in the cellular extract (CX) or conditioned media (CM) of sona (d) or sona-HA (e) S2 cells. Red arrows and black arrows mark full-length Sona and activated Sona, respectively. Asterisk marks the 22 kDa prodomain fragments. Arrowheads indicate intracellular fragments of Sona.