Figure 1.

The domain structure and gene organization of the MASP/C1r/C1s serine protease family. The first line shows the domain structure of an archetypical member of the family; the central three lines are representations of the exon-intron organization of the genes encoding the family members. The MASP-1 gene was recently found to contain another serine-protease-encoding region within it, encoding MASP-3, and was therefore renamed MASP-1/3. The bottom line shows the alternative splicing pattern of MASP-1 and MASP-3. Corresponding domains and the exons encoding them are shown in the same color. Abbreviations: CUB, C1r/C1s, sea urchin Uegf, bone morphogenetic protein domain; EGF-like, similar to epidermal growth factor; SCR, short consensus repeat.