Homocysteine modifies structural and functional properties of fibronectin and interferes with the fibronectin-fibrillin-1 interaction.
Homocysteine modifies structural and functional properties of fibronectin and interferes with the fibronectin-fibrillin-1 interaction.
复制标题
DOI：
10.1021/bi200183z
复制
发表时间：
2011-06-14
期刊：
影响因子：
2.9
通讯作者：
Reinhardt DP
中科院分区：
文献类型：
--
作者：
Hubmacher D;Sabatier L;Annis DS;Mosher DF;Reinhardt DP
同型半胱氨酸尿症是一种遗传性疾病，导致血浆和组织中同型半胱氨酸水平升高。一些骨骼和眼睛的症状，如长骨过度生长、脊柱侧弯和异位晶状体，与马凡综合征的症状重叠。马凡综合征是由细胞外基质蛋白纤维蛋白-1突变引起的。我们以前发现，纤维蛋白-1是同型半胱氨酸的靶标，同型半胱氨酸化的纤维蛋白-1在细胞外基质中的沉积受到影响。由于纤维连接蛋白-1的组装严重依赖于纤维连接蛋白，我们分析了纤维连接蛋白同型半胱氨酸化的后果及其与纤维连接蛋白-1的相互作用。细胞纤维连接蛋白和蛋白降解片段被同型半胱氨酸化，并在与重组纤维蛋白-1和肝素的不同相互作用试验中被检测。纤维连接蛋白同型半胱氨酸化始终影响纤维连接蛋白-纤维蛋白-1的相互作用，而与肝素的相互作用不受影响。Western blotting显示，纤维连接蛋白同型半胱氨酸化，而不是半胱氨酸化，使纤维连接蛋白二聚体减少为单体。用三种单抗对同型半胱氨酸化的纤维连接蛋白进行了EL ISA分析，发现含有FNI2、FNI4和FNI9的二硫键结构发生了变化。利用荧光标记的纤维连接蛋白，我们研究了纤维连接蛋白同型半胱氨酸化对细胞培养中组装的影响。修饰后的纤维粘连蛋白在去新生基质掺入和初始组装方面存在缺陷。综上所述，我们在此定义了同型半胱氨酸化时纤维连接蛋白特有的结构变化，这些变化转化为纤维连接蛋白-纤维连接蛋白-1相互作用和纤维连接蛋白组装中的功能缺陷。由于纤维连接蛋白是各种细胞外蛋白网络的主要组织者，这些结构和功能的改变可能有助于同型半胱氨酸尿症和马凡综合征的发病。
Homocystinuria is a genetic disorder resulting in elevated levels of homocysteine in plasma and tissues. Some of the skeletal and ocular symptoms such as long-bone overgrowth, scoliosis and ectopia lentis overlap with symptoms seen in Marfan syndrome. Marfan syndrome is caused by mutations in the extracellular matrix protein fibrillin-1. We previously showed that fibrillin-1 is a target for homocysteine and that the deposition of homocysteinylated fibrillin-1 in the extracellular matrix is compromised. Since the assembly of fibrillin-1 is critically dependent on fibronectin, we analyzed the consequences of fibronectin homocysteinylation and its interaction with fibrillin-1. Cellular fibronectin and proteolytic fragments were homocysteinylated and tested in various interaction assays with recombinant fibrillin-1 and heparin. Fibronectin homocysteinylation consistently compromised the fibronectin-fibrillin-1 interaction, while the interaction with heparin was not affected. Fibronectin homocysteinylation, but not cysteinylation, reduced the fibronectin dimers to monomers as shown by Western blotting. ELISA analyses of homocysteinylated fibronectin with three monoclonal antibodies demonstrated structural changes in the disulfide-containing FNI domains FNI2, FNI4 and FNI9. Using fluorescently labeled fibronectin, we studied the consequence of fibronectin homocysteinylation on assembly in cell culture. Modified fibronectin showed deficiencies in de-novo matrix incorporation and initial assembly. In conclusion, we define here characteristic structural changes of fibronectin upon homocysteinylation that translate into functional deficiencies in the fibronectin-fibrillin-1 interaction and in fibronectin assembly. Since fibronectin is a major organizer of various extracellular protein networks, these structural and functional alterations may contribute to the pathogenesis of homocystinuria and Marfan syndrome.
登录
查看更多内容
影响因子：
39.3
作者：
Giusti, B;Porciani, MC;Pepe, G
通讯作者：
Pepe, G
影响因子：
9.3
作者：
Herrmann, M;Widmann, T;Herrmann, W
通讯作者：
Herrmann, W
影响因子：
6.9
作者：
GODYNA, S;MANN, DM;ARGRAVES, WS
通讯作者：
ARGRAVES, WS
影响因子：
4.8
作者：
Lin, GQ;Tiedemann, K;Reinhardt, DP
通讯作者：
Reinhardt, DP
影响因子：
15.3
作者：
ENGVALL, E;RUOSLAHTI, E;MILLER, EJ
通讯作者：
MILLER, EJ