Fig. 1. Characterization of P.p.n. strains transformed with sense or antisense constructs of CBEL cDNA. (A) Plasmids used for transformation. HPH, coding sequences of the hygromycin phosphotransferase HPH gene; Phsp70, promoter of a HSP70 gene from Bremia lactucae; Tham34, terminator of the HAM34 gene from B. lactucae; B, BamHI; E, EcoRI; S, SmaI. (B) Molecular characterization of the transformants. (a) Southern blot analysis. In each lane, EcoR1-fragmented genomic DNA from the untransformed control strain (c), and from twelve strains transformed either with plasmid pTHEX11 (EX11, 1-7) or plasmid pTHEX3 (EX3, 1-5), were analyzed and hybridized with a radiolabeled CBEL cDNA probe. (b) Northern blot analysis. Total RNA from the same strains was electrophoresed, blotted and probed with a CBEL cDNA probe. The size of CBEL transcripts is 1.3 kb. Relative amounts of blotted RNA were determined by hybridization with an 18S rRNA probe. (c) Immunodetection of CBEL protein. Protein extracts from the untransformed control strain (c) and from four strains transformed either with plasmid pTHEX11 (EX11, 1 and 4) or plasmid pTHEX3) (EX3, 5 and 3) were subjected to western blot analysis using an anti-CBEL polyclonal antiserum. The M_r of CBEL is 34x10³.