The functional study of antithrombin L99 mutation.
- VernacularTitle:抗凝血酶L99氨基酸位点突变对其功能的影响
- Author:
Tingting YU
1
;
Jing DAI
1
;
Qiulan DING
1
;
Qihua FU
1
;
Xuefeng WANG
1
Author Information
- Publication Type:Journal Article
- MeSH: Amino Acids; genetics; Animals; Antithrombin III; genetics; Antithrombin III Deficiency; genetics; Antithrombins; Drosophila; Factor Xa; genetics; Genetic Vectors; Humans; Mutation
- From: Chinese Journal of Hematology 2014;35(3):191-196
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo study the molecular mechanisms of inherited antithrombin (AT) deficiency caused by AT L99 mutation.
METHODSWild type (WT), L99V, L99A, L99I and L99S AT were purified from drosophila expression system. The binding capacity of AT and the low molecular weight heparin sodium was analyzed by the heparin binding assay. Surface plasmon resonance (SPR) was used to detect the binding ability of AT to thrombin (FIIa) or AT to coagulation factor Xa (FXa). The activity of AT(AT∶A)was detected by chromogenic assay.
RESULTSThe purified WT and mutant AT were at the same size. No additional band was observed by coomassie blue staining and western blot assay. Compared to the WT AT, the binding abilities of the low molecular weight heparin sodium to the AT L99V, L99A, L99I and L99S were (44.8±3.6)%, (118.9±14.0)%, (15.2±8.8)%, and(23.0±8.2)%, respectively. The binding abilities of FIIa to AT L99V, L99A, L99I and L99S were 13%, 57%, 3%, and 29%, while the binding of FXa to AT L99V, L99A, L99I and L99S were 7%, 51%, 1%, and 25%. The AT∶A of WT, L99V, L99A, L99I and L99S AT were 146.5%, 21.4%, 120.9%, 10.8%, and 39.0%, respectively.
CONCLUSIONThe binding abilities of AT to heparin, FIIa and FXa were damaged by the L99 mutation, which resulted in decreased AT∶A and inherited AT deficiency.
