Putative alternative splicing variant of X. laevis MMP2 (MMP2asv). A) Nucleotide and deduced amino acid sequences of MMP2asv. The protein contains, from the N-terminus to C-terminus, a signal peptide (underlined), the conserved sequence in the propeptide involved in the "cysteine-switch" (in bold letters), a truncated catalytic domain linked to a truncated hemopexin domain (separated by double slash lines). The predicted cleavage site between the propeptide and the catalytic domain is indicated by an arrow. B) Comparison of the full length and alternatively spliced X. laevis MMP2 exon/intron organization. Solid blocks stand for exons present in the mRNAs and lines are introns.