Fig. 6. The signalling protease box is essential for processing. (A) Amino acid sequence alignment showing the conserved sequence designated the signalling protease box. Identical and conserved (Phe/Tyr, Asp/Glu, Ser/Thr) residues are shadowed in grey. PacC sequences correspond as follows: AN, A.nidulans; AG, Aspergillus niger; AO, Aspergillus oryzae; PC, Penicillium chrysogenum; SS, Sclerotinia sclerotium; AC, Acremonium chrysogenum; NC, Neurospora crassa. Residue numbering for A.nidulans PacC is indicated above the sequence. The bold line corresponds to A.nidulans residues 479–502 removed by the PacCΔ13 deletion. (B) The relevant region of an EMSA gel showing that the PacCΔ13 deletion fully prevents processing.