Gel Formation of Recombinant Fibrinogen Lacking αC Termini
In order to examine the role of αC domains, especially the terminal region of it, of fibrinogen Aα chain in the fibrin gel formation, we prepared a recombinant fibrinogen, Aα570 fibrinogen. Aα570 fibrinogen is the fibrinogen that is truncated at Aα570 and lacks 40 amino acids at the terminus of the αC domain. We examined the thrombin-catalyzed polymerization by transmission spectroscopy and confocal laser scanning microscopy (CLSM). We found that Aα570 fibrinogen exhibited a significantly delayed aggregation showing the importance of the terminal region of the αC domain in the polymerization process. Contrary to the fact that the addition of glucose to the mixture of fibrinogen and thrombin results in a substantial delay of the lateral aggregation of protofibrils for the native fibrinogen, delaying effect due to the addition of glucose disappeared thoroughly in the case of Aα570 fibrinogen. Turbidity measurements dependent upon the wavelength in the time course of gelation showed that mass per unit fiber length of Aα570 fibrinogen decreased significantly compared to the native fibrinogen, and the lateral aggregation of protofibrils was hindered significantly. Those results are consistent with the CLSM measurements that the bundles of protofibrils of Aα570 fibrinogen are thinner and denser with more branching than those of the native one. It was confirmed that C-terminal region of the αC domain plays an important role in the lateral aggregation and glucose interferes the interacting process between the αC domains.
KeywordsFibrinogen Truncation αC domain Gelation Saccharides
Authors, K. Kubota and N. Okumura, thank Prof. S. T. Lord for providing the plasmid vector that encodes the fibrinogen Aa chain. This work was partly supported by the Grant for Joint Research Program of the Institute of Low Temperature Science, Hokkaido Univ. and by the Ministry of Education, Japan.
- 4.Veklich YI, Gorkun OV, Medved LV, Nieuwenhuizent W, Weisel JW (1993) J Biol Chem 268:13577Google Scholar
- 6.Lau HK (1993) Blood 81:3277Google Scholar
- 10.Masuda Y, Toyama Y, Kogure H, Kubota K, Ochiai M (2004) Trans MRS-J 29:3331Google Scholar
- 11.Langer BG, Weisel JW, Dinauer PA, Nagaswami C, Bell WR (1988) J Biol Chem 263:15056Google Scholar
- 14.Gorkun OV, Veklich YI, Weisel JW, Lord ST (1997) Blood 89:4407Google Scholar
- 15.Koopman J, Haverkate F, Grimbergen J, Egbring R, Lord ST (1992) Blood 80:1972Google Scholar
- 16.Maekawa H, Yamazumi K, Muramatsu S, Kaneko M, Hirata H, Takahashi N, de Bosch NB, Carvajal Z, Ojeda A, Arocha-Pinango CL, Matsuda M (1991) J Biol Chem 266:11575Google Scholar
- 19.Carr Jr ME, Gabriel DA, McDonagh J (1986) Biochem J 239:513Google Scholar
- 20.Kogure H, Kitazawa M, Toyama Y, Kubota K, Ochiai M (2003) Trans MRS-J 28:949Google Scholar
- 26.Sugo T, Nakamikawa C, Takano H, Mimuro J, Yamaguchi S, Mosesson MW, Meh DA, DiOrio JP,Takahashi N, Takahashi H, Nagai K, Matsuda M (1999) Blood 94:3806Google Scholar