Purification and cloning of a novel C-type lectin-like protein with platelet aggregation activity from Trimeresurus mucrosquamatus venom.
TMVA, a novel C-type lectin-like protein that induces platelet aggregation in a dose-dependent manner, was purified from the venom of Trimeresurus mucrosquamatus. It consists of two subunits, alpha (15536 Da) and beta (14873 Da). The mature amino acid sequences of the alpha (135 amino acids) and beta subunits (123 amino acids) were deduced from cloned cDNAs. Both of the sequences show great similarity to C-type lectin-like venom proteins, including a carbohydrate recognition domain. The cysteine residues of TMVA are conserved at positions corresponding to those of flavocetin-A and convulxin, including the additional Cys135 in the alpha subunit and Cys3 in the beta subunit. SDS-PAGE, mass spectrometry analysis and amino acid sequence showed that native TMVA exists as two convertible multimers of (alpha beta)(2) and (alpha beta)(4) with molecular weights of 63680 and 128518 Da, respectively. The (alpha beta)(2) complex is stabilized by an interchain disulfide bridge between the two alpha beta-heterodimers, whereas the stabilization of the (alpha beta)(4) complex seems to involve non-covalent interactions between the (alpha beta)(2) complexes.
Wei
Qin
Q
Department of Animal Toxicology, Kunming Institute of Zoology, Chinese Academy of Sciences, 650223, Yunnan, Kunming, People's Republic of China.
Lu
Qiu-Min
QM
Jin
Yang
Y
Li
Rui
R
Wei
Ji-Fu
JF
Wang
Wan-Yu
WY
Xiong
Yu-Liang
YL
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001792:Blood Platelets / Q000187:drug effects; D003001:Cloning, Molecular; D003435:Crotalid Venoms / Q000737:chemistry* / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D037181:Lectins, C-Type / Q000235:genetics* / Q000302:isolation & purification*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010974:Platelet Aggregation; D020539:Sequence Analysis, Protein; D017841:Trimeresurus; D014757:Viper Venoms / Q000235:genetics* / Q000302:isolation & purification* / Q000494:pharmacology
D003435:Crotalid Venoms; D018076:DNA, Complementary; D037181:Lectins, C-Type; C468283:TMVA protein, Trimeresurus mucrosquamatus; C029748:Trimeresurus venoms; D014757:Viper Venoms