HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 275, Issue 21, 15861-15867, May 26, 2000

This Article Full Text Full Text (PDF) Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Reddy, V. B. Articles by Lerner, E. A. Search for Related Content PubMed PubMed Citation Articles by Reddy, V. B. Articles by Lerner, E. A. Social Bookmarking                      What's this?

Chrysoptin Is a Potent Glycoprotein IIb/IIIa Fibrinogen Receptor Antagonist Present in Salivary Gland Extracts of the Deerfly^*

Vemuri B. Reddy, Kounga Kounga, Fabio Mariano, and Ethan A. Lerner

From the Cutaneous Biology Research Center, Massachusetts General Hospital and Department of Dermatology, Harvard Medical School, Charlestown, Massachusetts 02129

Salivary gland lysates of the deerfly (genus Chrysops) contain chrysoptin, an inhibitor of ADP-induced platelet aggregation, which presumably assists the fly in obtaining a blood meal. Chrysoptin has now been isolated, and its cDNA has been cloned and expressed. Chrysoptin was purified to homogeneity using anion exchange and hydrophobic interaction chromatography and found to be a protein with a molecular mass of 65 kDa as determined by gel electrophoresis. N-terminal amino acid sequencing allowed for the synthesis of degenerate oligonucleotides that led to cloning, from salivary gland specific mRNA, of the cDNA encoding this platelet inhibitor. No RGD sites are present in the predicted sequence. A search of GenBank^TM did not reveal significant sequence homology between chrysoptin and other proteins. The molecular mass predicted from the cDNA was 59 kDa. Predicted glycosylation and phosphorylation sites may account for this difference in molecular mass, as recombinant chrysoptin expressed in Sf21 cells had a molecular mass of 65 kDa, matching that of the natural protein. Chrysoptin functions by inhibiting the binding of fibrinogen to the fibrinogen/glycoprotein IIb/IIIa receptor on platelets with an IC₅₀ of 95 pmol. These results reveal that insect salivary glands are a source of fibrinogen receptor antagonists.

The nucleotide sequence(s) reported in this paper has been submitted to the GenBank^TM/EMBL Data Bank with accession number(s) AF169229.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati