| Literature References | 1. HUANG, T.F., SHEU, J.R. AND TENG, C.M.
A potent anti-platelet peptide, triflavin, from Trimeresurus flavoviridis
snake venom.
BIOCHEM.J. 277 351-357 (1991).
2. AU, L.C., HUANG, Y.B., HUANG, T.F., TEH, G.W., LIN, H.H. AND CHOO, K.B.
A common precursor for a putative hemorrhagic protein and rhodostomin, a
platelet aggregation inhibitor of the venom of Calloselasma rhodostoma -
Molecular cloning and sequence analysis.
BIOCHEM.BIOPHYS.RES.COMMUN. 181(2) 585-593 (1991).
3. PAINE, M.J.I., DESMOND, H.P., THEAKSTON, R.D.G. AND CRAMPTON, J.M.
Purification, cloning, and molecular characterization of a high molecular
weight hemorrhagic metalloprotease, jararhagin, from Bothrops-J raraca
venom - Insights into the disintegrin gene family.
J.BIOL.CHEM. 267(32) 22869-22876 (1992).
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| Documentation | The adhesion of platelets to the extracellular matrix, and platelet-platelet
interactions, are essential in thrombosis and haemostasis [1]. Platelets
adhere to damaged blood vessels, release biologically active chemicals, and
aggregate, a function that is inhibited in normal blood [1]. The binding
of fibrinogen to the glycoprotein IIb/IIIa complex of activated platelets
is essential to platelet aggregation and is induced by many agonists,
including ADP, collagen, thrombin, epinephrine and prostaglandin
endoperoxide analogue.
Snake venoms affect blood coagulation and platelet function in a complex
manner [2]: some induce aggregation and release reactions, and some inhibit
them [1]. Disintegrin, a component of some snake venoms, rather than
inhibiting the release reactions, operates by inhibiting platelet
aggregation, blocking the binding of fibrinogen to the receptor-glyco-
protein complex of activated platelets [2]. The role of disintegrin in
preventing blood coagulation renders it of medical interest, particularly
with regard to its use as an anti-coagulant [3].
DISINTEGRIN is a 2-element fingerprint that provides a signature for the
disintegrins. The fingerprint was derived from an initial alignment of 8
sequences: motif 1 includes the region encoded by PROSITE pattern
DISINTEGRINS (PS00427), which includes 5 conserved Cys residues involved
in disulphide bond formation (the motifs do not include the cell-attachment
tripeptide Arg-Gly-Asp as the surrounding residues are not sufficiently
well conserved). Two iterations on OWL22.1 were required to reach
convergence, at which point a true set comprising 39 sequences was
identified.
An update on SPTR37_9f identified a true set of 43 sequences.
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