Genetic characterization of the mRNAs encoding alpha-bungarotoxin: isoforms and RNA editing in Bungarus multicinctus gland cells.
Nucleic Acids Res
; 26(24): 5624-9, 1998 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-9837992
ABSTRACT
The mRNA encoding alpha-bungarotoxin (alpha-Butx) was prepared from the venom glands of Bungarus multicinctus by Cap-finder cDNA synthesis. The sequences of the 3'- and 5'-flanking regions including a signal peptide of alpha-Butx were almost identical with those of Elapidae and Hydrophiidae toxins, suggesting that they may have the same origin. Sixteen polymorphic mRNA sequences of alpha-Butx were detected from B.multicinctus gland cells. Analysis of the genomic DNA of alpha-Butx indicated that the polymorphic mRNA originated from one DNA sequence. Most of the mutations in alpha-Butx mRNA were silent and the hot-spot variations occurred at 78, 107, 129, 198 and 201 nt in alpha-Butx mRNA. Ten distinct protein sequences of alpha-Butx could be deduced from the polymorphic mRNA and one of the isoforms has already been isolated. Since alpha-Butx DNA is a single copy in the genome, the RNA polymorphism might result from post-transcriptional editing. These results indicate that the authentic alpha-Butx is in fact derived from edited mRNAs. RNA editing may contribute a common mechanism toward the diversity of alpha-neurotoxins in snake glands.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bungarotoxinas
/
RNA Mensageiro
/
Bungarus
Limite:
Animals
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Taiwan