Genes & Development 23: 105–117 (2008)
In the above-mentioned paper, there was an error in the primers used to detect the Kcnq1 transcript in mouse growing oocytes in Figure 5A. The Kcnq1 primers labelled Ex11-F and Ex12-R are in fact located in exons 10 and 11, respectively, so the RT–PCR product for Kcnq1 does not span the DMR located in intron 11. The authors have repeated the RT–PCR analysis using new primers located in exons 10 and 12 (sequences given in updated Supplemental Table 1) and with this primer pair they detect Kcnq1 transcripts traversing the intron 11 DMR in mouse growing oocytes (as shown in the corrected Fig. 5, below), using the same conditions as in the previous assay. This correction does not alter the conclusion of the study in any way.
Figure 5.
Transcription across maternal germline DMRs in oocytes is common among imprinted genes. (A, left) Schemes representing the imprinted loci analyzed—Igf2r, Grb10, Kcnq1, Zac1, and Impact—showing the locations of the primers used for RT–PCRs in relation to the germline DMRs (filled circles). The schemes are not to scale, and for simplicity, not all exons of the genes are shown. Characterized start sites or start sites determined by 5′RACE analysis are indicated by arrows, with those above the line representing start sites detected in somatic cells and those below the line representing start sites detected in oocytes. Novel exons identified by 5′RACE are shown as gray boxes. (Right) RT–PCRs for these loci for transcripts traversing the DMRs in day 5 (d5), day 10 (d10), day 15 (d15), and MII oocytes are shown (as in Fig. 1C). For both Igf2r and Grb10, RT–PCRs labelled with Ex1-F/Ex3-R1 assay transcripts from the canonical somatic promoter and RT–PCRs labelled with Un1-F/Ex3-R2 assay the novel start sites identified in oocytes by 5′RACE. The multiple bands for Zac1 reflect alternative splicing of the various 5′ untranslated exons, with exon 8 being the first coding exon. (B) RT–PCR analysis of transcripts for the H19 paternal germline DMR. The RT–PCR represents amplicon 4 from Schoenfelder et al. (2007). (C) RT–PCR analysis of transcripts crossing the intragenic CGIs of four nonimprinted genes. Gene Sp6 represents locus PvuII 44, Chst8 is PstI 53, Sema6c is PstI 58, and Adra1b is PvuII 66 from Song et al. (2005). In the schemes to the left, the locations of the CGIs are represented by the open circles. In each panel, the lanes marked “Co” represent control amplification from E13.5 embryo RNA. The left lanes on each gel show a 100-bp marker ladder. (nd) Not done.
The authors apologize for the error.