CAJ | 학술논문

目的通过观察聚蛋白多糖酶-1 (ADAMTS-4)与纤维连接蛋白(FN)以及瓜氨酸化的FN(cFN)的结合活性及结合后的酶解活性,探讨ADAMTS-4的活性调节机制.方法应用肽酰基精氨酸脱亚胺酶4(PADI4)对纤维连接蛋白(FN)进行瓜氨酸化并采用蛋白印迹法进行验证；应用酶联免疫吸附法测定FN和cFN与2种不同相对分子质量的ADAMTS-4的结合活性；使用聚蛋白多糖酶活性分析试剂盒测定2种ADAMTS-4的活性和其与FN、cFN结合后酶活性的变化.统计分析采用单因素方差分析,LSD-t检验或t检验.结果蛋白印迹法证实PADI4可以使FN瓜氨酸化为cFN; cFN与相对分子质量为93 000的ADAMTS-4的结合活性明显低于FN(分别为0.624±0.033,2.182±0.042;t=50.522,P＜0.01),而两者与缺失碳端的相对分子质量为53 000的ADAMTS-4的结合活性差异无统计学意义(分别为0.934±0.012,0.971±0.024; t=2.388,P＞0.05).相对分子质量为93 000的ADAMTS-4能够酶解聚蛋白多糖产生大量酶解产物[ARGxx肽段浓度:(0.908±0.088) nmol/L],与FN结合后降解聚蛋白多糖的能力明显下降[ARGxx肽段浓度:(0.573±0.000) nmol/L,P＜0.05],与cFN孵育后的ADAMTS-4降解聚蛋白多糖产生的ARGxx肽段浓度[(0.830±0.020) nmol/L]明显高于与FN孵育后产生的ARGxx肽段浓度[(0.573±0.000)nmol/L,P＜0.05].相对分子质量为53 000的ADAMTS-4的酶活性在与FN或cFN孵育前后酶活性无明显变化(P均＞0.05).结论 FN能结合ADAMTS-4并抑制它的活性,PADI4能将FN转化为cFN,cFN与ADAMTS-4的结合活性明显降低,从而对ADAMTS-4的活性抑制作用减弱.
목적 통과관찰취단백다당매-1 (ADAMTS-4)여섬유련접단백(FN)이급과안산화적FN(cFN)적결합활성급결합후적매해활성,탐토ADAMTS-4적활성조절궤제.방법 응용태선기정안산탈아알매4(PADI4)대섬유련접단백(FN)진행과안산화병채용단백인적법진행험증；응용매련면역흡부법측정FN화cFN여2충불동상대분자질량적ADAMTS-4적결합활성；사용취단백다당매활성분석시제합측정2충ADAMTS-4적활성화기여FN、cFN결합후매활성적변화.통계분석채용단인소방차분석,LSD-t검험혹t검험.결과 단백인적법증실PADI4가이사FN과안산화위cFN; cFN여상대분자질량위93 000적ADAMTS-4적결합활성명현저우FN(분별위0.624±0.033,2.182±0.042;t=50.522,P＜0.01),이량자여결실탄단적상대분자질량위53 000적ADAMTS-4적결합활성차이무통계학의의(분별위0.934±0.012,0.971±0.024; t=2.388,P＞0.05).상대분자질량위93 000적ADAMTS-4능구매해취단백다당산생대량매해산물[ARGxx태단농도:(0.908±0.088) nmol/L],여FN결합후강해취단백다당적능력명현하강[ARGxx태단농도:(0.573±0.000) nmol/L,P＜0.05],여cFN부육후적ADAMTS-4강해취단백다당산생적ARGxx태단농도[(0.830±0.020) nmol/L]명현고우여FN부육후산생적ARGxx태단농도[(0.573±0.000)nmol/L,P＜0.05].상대분자질량위53 000적ADAMTS-4적매활성재여FN혹cFN부육전후매활성무명현변화(P균＞0.05).결론 FN능결합ADAMTS-4병억제타적활성,PADI4능장FN전화위cFN,cFN여ADAMTS-4적결합활성명현강저,종이대ADAMTS-4적활성억제작용감약.
Objective To observe the inhibiting activities of fibronectin (FN) and citrullinated fibronectin (cFN) on disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4),and to explore the extracellular regulative mechanisms of ADAMTS-4.Methods FN was incubated with peptidylarginine deaminase type 4 (PADI4).Western blotting analysis was used to verify the citrullination of FN.The binding activity of FN and cFN to ADAMTS-4 were investigated by enzyme-linked immunosorbent assay (ELISA).The proteolytic ability of ADAMTS-4 after binding to FN and cFN were measured with the aggrecanase activity assay kit.One-way ANOVA,LSD-t test and t-test were used for statistical analysis.Results The immunosignal of citrulline was detected in FN after incubated with PADI4,but not in the absence of PADI4.A higher absorbance at 405 nm was detected when the full-length ADAMTS-4 protein was incubated with FN (2.182±0.042) than cFN (0.624±0.033; t=50.522,P＜0.01).Additionally,the recombinant ADAMTS-4 protein with a truncation at the C-terminus displayed low absorbance at 405 nm when the enzyme was incubated with both FN(0.971±0.024) and cFN(0.934±0.012; t=2.388,P＞0.05).Large amounts of ARGxx peptide were detected with full-length ADAMTS-4 in aggrecanase activity assay [(0.908±0.088) nmol/L],but significantly less when in the presence of FN and ADAMTS-4 [(0.573±0.000) nmol/L,P＜0.05].The production of this peptide was more when full-length ADAMTS-4 was incubated with cFN [(0.830±0.020) nmol/L,P＜0.05] than with FN.The reaction containing the truncated ADAMTS-4 without FN or cFN yielded the highest concentration of ARGxx peptide [(36.420±3.673) nmol/L],peptide production was not significantly altered when FN [(41.099±0.101) nmol/L] or eFN [(41.064±0.083) nmol/L] were added to the reaction.Conclusion FN could bind to ADAMTS-4 and inhibit its proteolytic activity.After citrullinated by PADI4,the binding activity of cFN is weakened and less inhibition to ADAMTS-4.