Figure 5.

Accumulation of the Secreted 45- and 95-kD Forms.

Protoplasts were isolated from wild-type (lanes 1 to 4) or zeolin-expressing (lanes 5 to 8) tobacco leaves and incubated for 24 h in the presence (+) or absence (−) of 20 mM 2-ME. Aliquots of protoplast homogenates (P) and incubation medium (M) of an equivalent amount of protoplasts were analyzed by SDS-PAGE and protein blot using anti-phaseolin antiserum. The positions of zeolin (arrowhead), the 45-kD form (arrow), and the 95-kD putative O-glycosylated zeolin (asterisk) are indicated. Numbers at left indicate the positions of molecular mass markers in kD.