Figure 2

From: Characterization of the STK11 splicing variant as a normal splicing isomer in a patient with Peutz–Jeghers syndrome harboring genomic deletion of the STK11 gene

Figure 2

(a) Reverse transcription-PCR (RT-PCR) products encompassing STK11 exons 1–3 were analyzed. All samples were pretreated with puromycin before RNA extraction. Each lane exhibits the wild-type band (236 bp) and upper band (367 bp). (b) Electropherograms of RT-PCR products after gel extraction of the upper band. The signal from the splicing variant was detected. (c) Genomic organization of the STK11 gene and messenger RNA (mRNA) (NM_000455.4), whose coding sequence spans from 1,116 to 2,417 bp. The annealing positions and sequences of primers used for RT-PCR are shown. An AG-GT splicing motif sequence located in LINE/L1 and SINE/Alu elements worked as the cryptic splicing site, and the 131-bp sequence was spliced out as the aberrant RNA isomer in RT-PCR from puromycin-treated peripheral blood lymphocytes. The location of LINE/L1 or SINE/Alu element occupies 71 bp in the forward part or 55 bp in the backward part of the 131-bp fragment, respectively. (d) Patient’s STK11 gene alleles. This patient had a genomic deletion of exon 1 in the STK11 gene, as we previously described.7 Allele 1 shows an aberrant allele with an exon 1 deletion. Allele 2 shows a normal allele with the splicing variant that resulted in a premature terminal codon at exon 2. The annealing positions of primers used for RT-PCR are shown as arrows. The forward primer for RT-PCR cannot anneal to the exon 1-deleted mRNA.