Gel analysis of GFP RNAs. Lanes 1 and 3, sense RNA before and after RNase One treatment; lanes 2 and 4, antisense RNA before and after RNase One treatment; lanes 5 and 6, dsRNA before and after RNase One treatment; lane 7, 100 bp markers with a brighter band at 600 bp.

Embryonic abnormalities caused by dsRNA injection. (A) An embryo injected with pouII-1 sense RNA at the 50% epiboly stage. (B) An abnormal embryo injected with pouII-1 dsRNA at the same stage as in A. (C) An embryo injected with GFP sense RNA at the 75% epiboly stage. (D) An abnormal embryo injected with GFP dsRNA at the same stage as in C. (E) A 20-h embryo injected with pouII-1 sense RNA. (F) A 20-h abnormal embryo injected with pouII-1 dsRNA. (G) A 20-h abnormal embryo injected with GFP dsRNA. (H) Severely abnormal embryos at 20 hpf injected with intronT dsRNA.

Effect of dsRNA on GFP expression. (A) A transgenic embryo at 24 hpf showing GFP in the ICM. (B–D) Abnormal 24-h transgenic embryos that were injected with GFP dsRNA. (E) Embryos injected with GFP mRNA alone. (F) Embryos co-injected with GFP mRNA and GFP dsRNA. (G) Embryos co-injected with GFP mRNA and pouII-1 dsRNA. Embryos in E–G all are at the sphere stage.

DsRNA-induced nonspecific degradation of mRNA. The injected embryos were collected at the dome stage and used for in situ hybridization with GFP (A–C) or pouII-1 (D–F) antisense probe. (A) Embryos injected with GFP mRNA (150 pg/e) alone. (B) Embryos co-injected with GFP mRNA and GFP dsRNA (75 pg/e). (C) Embryos co-injected with GFP mRNA and pouII-1 dsRNA (75 pg/e). (D) Embryos injected with pouII-1 sense RNA (150 pg/e). (E) Embryos injected with GFP dsRNA (150 pg/e). (F) Embryos injected with pouII-1 dsRNA (150 pg/e).