Figure 8.

Stability and intracellular transport of LMW-GS in tobacco protoplasts. A, Protoplasts were transfected with vector alone (vector) or constructs encoding either the B11-33-HA or the C(25, 230)S-HA protein, labeled for 1 h with [³⁵S]Cys and [³⁵S]Met and then chased for the times indicated. Proteins were immunoselected from cell homogenates with anti-HA antibodies and analyzed by reducing SDS-PAGE and fluorography. B, Protoplasts were transfected and pulse-labeled as in A and then chased for the times indicated. After fractionation into a membrane and a soluble fraction as in “Materials and Methods,” proteins were immunoselected with anti-HA or anti-BiP antibodies and analyzed by reducing SDS-PAGE and fluorography. The arrowhead indicates the position of the BiP polypeptide.