Purification, characterization and genomic organization of KTX2 from Androctonus australis, a new inhibitor of voltage and calcium activated K+ channel

Laraba-Djebari, Fatima; Legros, Christian; Crest, Marcel; Céard, Brigitte; Romi, Régine; Mansuelle, Pascal; Jacquet, G; Rietchoten, J. Van; Gola, Maurice; Rochat, H.; Bougis, Pierre E.; Martin‐Eauclaire, Marie‐France

doi:10.1016/0041-0101(96)80991-3

Cited by 6 publications

(27 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Two encoded the KTX 2 precursor and differed only in their 5' part (nt 7-27): they did not contain the Mbol restriction site (GATC) on their 5' sides as was expected. Surprisingly, the third kind fragment was larger (500 bp) than the others (470 bp) and encoded part of the N-terminus of the KTXj precursor [4]. The 5' side of the putative KTXi gene contains the expected Mbol site.…”

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

“…The Genes of toxins active on voltage-dependent Na + channels, i.e. from top to bottom, the oc-toxin AaH I' from the Tunisian Androctonus australis [4]; the ß-toxin y from the Brazilian scorpion Tityus serrulatus [14]; gene of toxins active on the voltage-dependent K + channel, i.e. KTX 2 (this work); gene of the defensin from the fly Drosophila megalogaster [15].…”

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

“…from top to bottom, the a-toxin AaH I' from the Tunisian Androctonus australis [19]; the ß-toxin y from the Brazilian scorpion Tityus serrulatus [20]; cDNA of toxins active on the voltage-dependent K + channel, i.e. KTX2 [4]; gene of the defensin from the fly Drosophila megalogaster [15]. high A+T content Comparison of sequenced scorpion toxin genes: genes of toxins active on voltage-dependent Na + channels, i.e.…”

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

“…high A+T content Comparison of sequenced scorpion toxin genes: genes of toxins active on voltage-dependent Na + channels, i.e. from top to bottom, the ß-toxin y from the Brazilian scorpion Tityus serrulatus [14]; the a-toxin AaH I' from the Tunisian Androctonus australis [4] and the a-toxin Ts IV-5 from the Brazilian scorpion Tityus serrulatus [13]; gene of toxins active on voltage-dependent K + channels (this work); A+T content of intron sequences; 5' and 3' intron boundaries of the toxins compared to the proposed arachnid consensus sequence for 5' and 3' intron boundaries [14]. Sizes of the various introns.…”

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

“…These bridges appear to conserve the relative position of the ß-sheets and the oc-helix [3]. A 370 bp cDNA encoding the kaliotoxin 2 (KTX 2 ) precursor (a 37 amino acid residues peptide) purified from the North African scorpion Androctonus australis and acting as a high affinity blocker of K + channels, was previously obtained by PCR amplification [4]. The present work is the second step towards analyzing the genomic organization of the scorpion toxin genes.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

1997

View full text Add to dashboard Cite

A single intron of 87 bp, close to the region encoding the C-terminal part of the signal peptide, was found in the gene of the 'short' scorpion toxin kaliotoxin 2 of Andvoctonus australis acting on various types of K + channels. Its A+T content was particularly high (up to 86%). By walking and ligation-mediated PCR, the promoter sequences of the kaliotoxin 2 gene of Androctonus australis were studied. The transcription unit of the gene is 390 bp long. Consensus sequences were identified. The genes of 'short' scorpion toxins active on K + channels are organized similarly to those of the 'long' scorpion toxins active on Na + channels and not like those of structurally related insect defensins, which are intronless.

show abstract

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

Section: Determination Of the Nucleic Sequences Flanking The Ktx 2 Genementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

1997

View full text Add to dashboard Cite

show abstract

Characterization of a new peptide from Tityus serrulatus scorpion venom which is a ligand of the apamin‐binding site

et al. 1996

View full text Add to dashboard Cite

A new ligand (Ts s:) of the apamin binding site on rat brain synaptosomes (Ko.s = 300 pM) was purified and characterized from the venom of Tityus serrulatus. It is a polypeptide toxin of 35 amino acid residues, with three disulfide bridges. Its cDNA was amplified from a venom gland cDNA library and the nucleotide sequence determined. A model of Ts • was constructed by amino acid replacement using charybdotoxin structure as determined by 1H nuclear magnetic resonance as starting model.

show abstract

Influence of a NH₂‐terminal extension on the activity of KTX2, a K⁺ channel blocker purified from Androctonus australis scorpion venom

Legros¹,

Feyfant²,

Sampiéri³

et al. 1997

FEBS Letters

View full text Add to dashboard Cite

A cDNA encoding a short polypeptide blocker of K + channels, kaliotoxin 2 (KTX2), from the venom of the North African scorpion Androctonus australis was expressed in the periplasmic space of Escherichia coli. KTX2 was produced as a fusion protein with the maltose binding protein followed by the recognition site for factor Xa or enterokinase preceding the first amino acid residue of the toxin. The fully refolded recombinant KTX2 (rKTX2) was obtained (0.15-0.30 mg/1 of culture) and was indistinguishable from the native toxin according to chemical and biological criteria. An N-extended analogue of KTX2 exhibiting three additional residues was also expressed. This analogue had 1000-fold less affinity for the 125 I-kaliotoxin binding site on rat brain synaptosomes than KTX2. Conformational models of KTX2 and its mutant were designed by amino acid replacement using the structure of agitoxin 2 from Leiurus quinquestriatus as template, to try to understand the decrease in affinity for the receptor.

show abstract

Purification, characterization and genomic organization of KTX2 from Androctonus australis, a new inhibitor of voltage and calcium activated K+ channel

Cited by 6 publications

References 0 publications

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

Characterization of a new peptide from Tityus serrulatus scorpion venom which is a ligand of the apamin‐binding site

Influence of a NH₂‐terminal extension on the activity of KTX2, a K⁺ channel blocker purified from Androctonus australis scorpion venom

Contact Info

Product

Resources

About

Purification, characterization and genomic organization of KTX2 from Androctonus australis, a new inhibitor of voltage and calcium activated K+ channel

Cited by 6 publications

References 0 publications

Genomic organization of the KTX2 gene, encoding a ‘short’ scorpion toxin active on K+ channels

Genomic organization of the KTX2 gene, encoding a ‘short’ scorpion toxin active on K+ channels

Characterization of a new peptide from Tityus serrulatus scorpion venom which is a ligand of the apamin‐binding site

Influence of a NH2‐terminal extension on the activity of KTX2, a K+ channel blocker purified from Androctonus australis scorpion venom

Contact Info

Product

Resources

About

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

Genomic organization of the KTX₂ gene, encoding a ‘short’ scorpion toxin active on K⁺ channels

Influence of a NH₂‐terminal extension on the activity of KTX2, a K⁺ channel blocker purified from Androctonus australis scorpion venom