Figure 1

Novel cis -spliced introns in Giardia intestinalis strain WB (assemblage A). A. Evidence for cis-splicing of the intron in the ORF AACB02000068-1-10039-10248 (orfA). PCR products amplified from gDNA, cDNA, and distilled water were applied to the left, middle, and right lanes, respectively. The expected lengths of the amplicons from gDNA and cDNA are 163 and 122 bp, respectively. The amplicon marked by an arrowhead was cloned and sequenced. B. Evidence for cis-splicing of the intron in the ORF AACB02000001-6-305427-304747 (orfB). Details are described in A. The expected lengths of the amplicons from gDNA and cDNA are 175 and 142 bp, respectively. C. Intron position in the ORF AACB02000068-1-10039-10248 (orfA). Nucleotide sequence from positions 1,459,142 to 1,459,363 of chromosome no. 5 is shown. The initiation codon of the originally annotated hypothetical protein GL50803_37070 is enclosed by an open square. The intron region is shaded. The 5′ terminus of the transcript (arrow) was determined experimentally. The revised amino acid sequence is provided as one-letter code. D. Intron position in the ORF AACB02000001-6-305427-304747 (orfB). Nucleotide sequence from positions 1,071,651 to 1,072,459 of chromosome no. 3 is shown. The initiation codon of the originally annotated hypothetical protein GL50803_15525 is enclosed by an open square. Other details are same as described in C.