Screening of a cDNA library revealed that Castanea crenata agglutinin (CCA) consists of two homologous protomers: CCA, which has been reported previously, and its isoform, designated CCA-Q, which contains an additional glutamine residue inserted at position 153 of CCA. PCR-Southern and subsequent analyses of the genomic sequence indicated that both CCA and CCA-Q should be translated from the same gene, CCA, which consists of four exons and three introns. Therefore, the difference may be caused by a type of alternative splicing. PCR-Southern analysis also indicated the existence of another gene, sCCA, which showed high identity to exon 1, intron 1 and exon 4 of CCA. In addition, the entire sCCA gene was transcribed into an mRNA with no obvious open reading frame, although the amount of transcribed product was less than 1/100 of the level of the CCA transcript. Thus, sCCA is estimated to be a pseudogene. These results suggest that no CCA isoforms encoded by different genes are present in Japanese chestnut trees, except for the presence of a homolog pseudogene.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.