Stover C M, Thiel S, Thelen M, Lynch N J, Vorup-Jensen T, Jensenius J C, Schwaeble W J
Department of Microbiology and Immunology, University of Leicester, United Kingdom.
J Immunol. 1999 Mar 15;162(6):3481-90.
Mannan-binding lectin (MBL) forms a multimolecular complex with at least two MBL-associated serine proteases, MASP-1 and MASP-2. This complex initiates the MBL pathway of complement activation by binding to carbohydrate structures present on bacteria, yeast, and viruses. MASP-1 and MASP-2 are composed of modular structural motifs similar to those of the C1q-associated serine proteases C1r and C1s. Another protein of 19 kDa with the same N-terminal sequence as the 76-kDa MASP-2 protein is consistently detected as part of the MBL/MASP complex. In this study, we present the primary structure of this novel MBL-associated plasma protein of 19 kDa, MAp19, and demonstrate that MAp19 and MASP-2 are encoded by two different mRNA species generated by alternative splicing/polyadenylation from one structural gene.
甘露聚糖结合凝集素（MBL）与至少两种MBL相关丝氨酸蛋白酶MASP-1和MASP-2形成多分子复合物。该复合物通过与细菌、酵母和病毒上存在的碳水化合物结构结合，启动补体激活的MBL途径。MASP-1和MASP-2由与C1q相关丝氨酸蛋白酶C1r和C1s相似的模块化结构基序组成。始终检测到一种19 kDa的蛋白质，其N端序列与76 kDa的MASP-2蛋白相同，作为MBL/MASP复合物的一部分。在本研究中，我们展示了这种新型19 kDa的MBL相关血浆蛋白MAp19的一级结构，并证明MAp19和MASP-2由一个结构基因通过可变剪接/聚腺苷酸化产生的两种不同mRNA编码。
