Genomic structure of a potassium channel toxin from Heteractis magnifica

FEBS Letters

Jeyaseelan, Kandiah¹  Chung, Max C.M¹  Gendeh, Gurmil S¹ 

[1] Department of Biochemistry, National University of Singapore, 10 Kent Ridge Crescent, 119260 Singapore, Singapore

关键词: Potassium channel toxin;    Heteractis magnifica;   

DOI  :  10.1016/S0014-5793(97)01365-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We provide information on the gene encoding the K⁺ channel toxin, HmK, of the sea anemone Heteractis magnifica. A series of DNA amplifications by PCR, which included the amplification of the 5′-untranslated region of the gene, showed that an intron of 402 nucleotides separated the sequence that encodes the matured toxin from the signal peptide sequence. A second 264 nucleotide intron interrupted the 5′-untranslated region of the previously reported HmK cDNA. Two possible transcription-initiation sites were identified by primer extension analysis. Corresponding TATA-box consensus sequences, characteristic of a promoter region, were also located from PCR products of uncloned libraries of adaptor-ligated genomic DNA fragments. The coding region for matured HmK is intronless. The same is also true for other sea anemone toxins reported thus far. More notably, a similar intron-exon organization is present in other ion channel-blocking toxins from scorpions implying that molecules having similar functions share a similar organization at the genomic level suggesting a common path of evolution.

【 授权许可】

Unknown