Figure 8.

Association between Zeolin and BiP.

Protoplasts from transgenic tobacco expressing zeolin were pulse-labeled with [³⁵S]Met and [³⁵S]Cys for 1 h and subjected to chase for the indicated times in the presence (+) or absence (−) of 20 mM 2-ME. For all panels, chase points and in vivo 2-ME treatments are as in (A). Total homogenates were prepared from protoplasts, using homogenation buffer supplemented with 2-ME ([B] and [D]) or without the reducing agent ([A] and [C]), and immunoselected using anti-BiP ([A] and [B]) or anti-phaseolin ([C] and [D]) antiserum. Analysis was by SDS-PAGE and fluorography. The positions of zeolin (closed arrowheads) and BiP (open arrowheads) are indicated. Numbers at right indicate the positions of molecular mass markers in kD.