Advanced

Role of the N-terminal EGF module of coagulation factor IX in activation of factors IX and X.

Persson, Kristina LU (2002) In Scandinavian journal of clinical and laboratory investigation 62(Suppl 237). p.13-18
Abstract
Absence or reduced activity of coagulation factor IX (FIX) causes the severe bleeding disorder haemophilia B. FIX contains a Gla module, two epidermal growth factor-like (EGF) modules, and a serine protease region. I characterized a monoclonal antibody and found that it recognizes an epitope around residues 72 and 80 in the C-terminal part of EGF1 in human FIX. The antibody exhibited 10-fold greater affinity for activated FIX (FIXa) than for the zymogen FIX, indicating the existence of intra-molecular communication between the serine protease region and EGF1. Binding of the antibody did not affect the amidolytic activity of FIXa, hence I could use the antibody during activation of FIX to show that the C-terminal part of EGF1 is of... (More)
Absence or reduced activity of coagulation factor IX (FIX) causes the severe bleeding disorder haemophilia B. FIX contains a Gla module, two epidermal growth factor-like (EGF) modules, and a serine protease region. I characterized a monoclonal antibody and found that it recognizes an epitope around residues 72 and 80 in the C-terminal part of EGF1 in human FIX. The antibody exhibited 10-fold greater affinity for activated FIX (FIXa) than for the zymogen FIX, indicating the existence of intra-molecular communication between the serine protease region and EGF1. Binding of the antibody did not affect the amidolytic activity of FIXa, hence I could use the antibody during activation of FIX to show that the C-terminal part of EGF1 is of importance for the interaction with FXIa but not with FVIIa/TF. Considering activation of FX, it is a matter of debate whether EGF1 or FIXa interacts directly with FVIIIa. I activated FX in the presence and absence of the antibody and/or FVIIIa. The addition of antibody caused only a minor decrease in k cat,app , and the major increase in k cat,app caused by the addition of FVIIIa occurred even in the presence of the antibody. This implies that EGF1 of FIXa is not directly involved in interaction with FVIIIa in the Xase complex. A model of the FIXa-FVIIIa complex, based on my findings and results from the literature, was constructed and indicated that EGF1 of FIXa does not interact directly with FVIIIa. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
monoclonal antibody, EGF module, coagulation, factor X, factor IX
in
Scandinavian journal of clinical and laboratory investigation
volume
62
issue
Suppl 237
pages
13 - 18
publisher
Taylor & Francis
external identifiers
  • wos:000180064200004
  • scopus:0036460548
ISSN
0085-591X
DOI
10.1080/003655102762377448
language
English
LU publication?
yes
id
fd27ef49-a65c-42c3-8d51-26d9b8e04aa8 (old id 114475)
date added to LUP
2007-07-26 14:34:34
date last changed
2017-01-01 07:26:45
@article{fd27ef49-a65c-42c3-8d51-26d9b8e04aa8,
  abstract     = {Absence or reduced activity of coagulation factor IX (FIX) causes the severe bleeding disorder haemophilia B. FIX contains a Gla module, two epidermal growth factor-like (EGF) modules, and a serine protease region. I characterized a monoclonal antibody and found that it recognizes an epitope around residues 72 and 80 in the C-terminal part of EGF1 in human FIX. The antibody exhibited 10-fold greater affinity for activated FIX (FIXa) than for the zymogen FIX, indicating the existence of intra-molecular communication between the serine protease region and EGF1. Binding of the antibody did not affect the amidolytic activity of FIXa, hence I could use the antibody during activation of FIX to show that the C-terminal part of EGF1 is of importance for the interaction with FXIa but not with FVIIa/TF. Considering activation of FX, it is a matter of debate whether EGF1 or FIXa interacts directly with FVIIIa. I activated FX in the presence and absence of the antibody and/or FVIIIa. The addition of antibody caused only a minor decrease in k cat,app , and the major increase in k cat,app caused by the addition of FVIIIa occurred even in the presence of the antibody. This implies that EGF1 of FIXa is not directly involved in interaction with FVIIIa in the Xase complex. A model of the FIXa-FVIIIa complex, based on my findings and results from the literature, was constructed and indicated that EGF1 of FIXa does not interact directly with FVIIIa.},
  author       = {Persson, Kristina},
  issn         = {0085-591X},
  keyword      = {monoclonal antibody,EGF module,coagulation,factor X,factor IX},
  language     = {eng},
  number       = {Suppl 237},
  pages        = {13--18},
  publisher    = {Taylor & Francis},
  series       = {Scandinavian journal of clinical and laboratory investigation},
  title        = {Role of the N-terminal EGF module of coagulation factor IX in activation of factors IX and X.},
  url          = {http://dx.doi.org/10.1080/003655102762377448},
  volume       = {62},
  year         = {2002},
}