Dataset Information

Gene sequence analysis of toxins from the spider Phoneutria nigriventer revealed an intronless feature.

ABSTRACT:

Background

Phoneutria nigriventer spider venom contains several cysteine-rich peptide toxins that act on different ion channels. Despite extensive studies on its venom and description of cDNA sequences of several of its toxin precursors, the gene structure of these toxins remains unknown.

Methods

Genomic regions encoding the precursors of three previously characterized P. nigriventer toxins - PnTx1, PnTx2-5 and PnTx4(5-5) - were amplified by PCR using specific primers. PCR fragments were cloned and sequenced. Obtained sequences were compared with their corresponding cDNA sequences.

Results

The size of PCR fragments obtained and sequences corresponding to genomic regions encoding for the toxin precursors matched their cDNA sequences.

Conclusions

Despite a few nucleotide substitutions in the genomic regions encoding for the toxin precursors when compared with cDNA sequences, the results of the present work indicate that P. nigriventer toxins do not contain introns in their genes sequences.

SUBMITTER: Paiva ALB

PROVIDER: S-EPMC7199488 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Gene sequence analysis of toxins from the spider <i>Phoneutria nigriventer</i> revealed an intronless feature.

Paiva Ana Luiza Bittencourt ALB Matavel Alessandra A Silva Bruno César Souza BCS Guerra-Duarte Clara C Diniz Marcelo Ribeiro Vasconcelos MRV

The journal of venomous animals and toxins including tropical diseases 20200430

<h4>Background</h4><i>Phoneutria nigriventer</i> spider venom contains several cysteine-rich peptide toxins that act on different ion channels. Despite extensive studies on its venom and description of cDNA sequences of several of its toxin precursors, the gene structure of these toxins remains unknown.<h4>Methods</h4>Genomic regions encoding the precursors of three previously characterized <i>P. nigriventer</i> toxins - PnTx1, PnTx2-5 and PnTx4(5-5) - were amplified by PCR using specific primer ...[more]

PMID: 32395122

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