Sialokinin I and II: vasodilatory tachykinins from the yellow fever mosquito Aedes aegypti.

Abstract

The saliva of the mosquito Aedes aegypti has previously been reported to contain a 1400-Da peptide with pharmacological properties typical of a tachykinin. In the present study this vasodilator has been purified to homogeneity and found to consist of two peptides: sialokinin I, with the sequence Asn-Thr-Gly-Asp-Lys-Phe-Tyr-Gly-Leu-Met-NH2, and sialokinin II, identical to sialokinin I except for an Asp in position 1. These peptides are present in amounts of 0.62 and 0.16 pmol (711 and 178 ng), respectively, per salivary gland pair. When assayed on the guinea pig ileum, both peptides are as active as the mammalian tachykinin substance P, with K0.5 values of 5.07, 6.58, and 4.94 nM for sialokinin I, sialokinin II, and substance P, respectively.

• Authors: D E Champagne, J M Ribeiro
• Journal: Proceedings of the National Academy of Sciences of the United States of America (Proc Natl Acad Sci U S A) Vol. 91 Issue 1 Pg. 138-42 (Jan 04 1994) ISSN: 0027-8424 [Print] United States
• PMID: 8278354 (Publication Type: Comparative Study, Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Salivary Proteins and Peptides
• Tachykinins
• Vasodilator Agents
• sialokinin I
• sialokinin II

Topics

• Aedes (chemistry)
• Amino Acid Sequence
• Animals
• Chromatography, High Pressure Liquid
• Molecular Sequence Data
• Salivary Proteins and Peptides (chemistry, pharmacology)
• Sequence Alignment
• Sequence Homology, Amino Acid
• Tachykinins (chemistry, isolation & purification, pharmacology)
• Vasodilator Agents